Audio Yamaha DSP-A2070 Digital Sound Field Processing Amplifier

[RishiGuru]

I got lucky. Very luck. Why?

Coz I got a deal to have a Yamaha DSP-A2070 7.1 channel integrated amplifier at INR 8K [USD $160].

Yamaha DSP-A2070

This previous owner bought this amplifier back in 1996 in U.K and was using it since. Last year he thought of an upgrade and outsourced a Marantz SR6003 A/V reciever to replace the DSP-A2070.

He says after some months of extensively using the SR6003, he found though it supports all the latest movie formats and provide options like USB so he can connect his iPod, it crucially lacked in terms of audio performance and the level of sound quality that the DSP-A2070 was able to achieve. According to him 2-channel performance of this Yamaha is something special and the SR6003 cannot hold a candle to it. Later he got a Krell and decided to sell both the SR6003 & DSP-A2070.

For starters DSP-A2070 is not a A/V Receiver like SR6003, actually you cannot call it a receiver since it lacks a tuner, and it has no video processing capabilities. It is just a 7.1 channel integrated amplifier purely devoted to audio & its digital soundfield processing.

The amp is plane Jane & conservative looking. But it weighs a hefty 21kilos [46 lbs]. The power supply section must be almighty which is denoted by its weight.

Stats of Yamaha DSP-A2070

----------------------------------

1) Full name : Yamaha DSP-A2070 Digital Sound Field Processing Amplifier

2) Released : 1993

3) Price on release : $2000 (INR 1 lakh approx)

4) Awards : In 1993 won the best Home Theater System award given by European Imaging & Sound Association(EISA) www.eisa.eu --> Awards

5) Minimum continuous power per channel(RMS) @ 20Hz~20kHz @ 0.015% THD @ 6 ohms:

Main stereo speakers(2 units) : 100 watts/ each

Center speaker(1 unit) : 100 watts

Effect speakers (4 units) : 26 watts/ each

Total minimum continuous power of the system : 100 + 100 + 100 + 26 + 26 + 16 + 26 = 404 watts @ 6 ohms

6) Minimum dynamic power per main channels : 130 watts @ 8 ohms / 160 watts @ 6 ohms / 215 watts @ 4 ohms

7) Dynamic Headroom : 2.0db @ 6 ohms

-----------------------------------------------------

 

[RishiGuru]

Auditioning the DSP-A2070

As audiophiles love to provide audition, he was more than happy to connect the DSP-A2070 main left and right channels to his awesome Bower & Wilkins Diamond 800 floor-standers, while the four effect channels at the four corners of the room was Dali Lektor's having 8 inch drivers. The center channel was a Klipsch with two 8 inch drivers but I was not able to identify which model.

Mind you all the audio channel of main + center + effect speakers connected to the DSP-A2070 can individually travel throughout the entire audio frequency bandwidth of 20Hz~20kHz.

For me what good is a feature packed receiver/ amplifier or any A/V gear for that matter if it cannot deliver the goods in sonic performance? My viewpoint is sound first, features second. With that here is my subjective impression of the DSP-A2070.

One area Yamaha flagship multi channel amplifiers/receivers have always excelled in my opinion is two-channel audio. Unlike many lesser products, Yamaha never disappoints anyone in this regard. In my latest experience the DSP-A2070 it was no different.

I was immediately overwhelmed by the almost limitless dynamic range I was hearing in two-channel stereo with this amplifier. Its big, bold sound never lacked refinement or poise even when driven to my personal listening limits with these full range awesome speakers at a moderately large listening room.

The auditioning was done without any use of subwoofer. This did not seem problematic to me since the DSP-A2070 has a superb noise floor in all listening modes, partly attributed to careful circuit layout and implementation of the absolute best DAC's on the market of its time. The good news is Yamaha spared no expense and implemented these high quality Burr Brown DAC's on all channels , including the presence and subwoofer channels - and in balanced configuration!

SACD: Patricia Barber - Café Blue

This remains one of my benchmark SACD's for good reason - lumpy jazz in a smooth jazz environment. You won't find repetitive and annoying saxophone scales, single stroke drumming, and simplistic guitar rifts. Instead you're showered with snappy jazz and provocative lyrics, slamming drums and memorable instrumental solos. The SACD layer of Track #2, "Morning Grace" sounded about as good as I've ever heard which in one word would best be summed up as "phenomenal".

CD: Brazilian Bossa Brazilian Bossa

I was stunned by the quality of the recordings of track #'s 1, 3 and 6.I constantly had to convince myself by looking at the front panel of the DSP-A2070 that I was listening to amplifier belonging to the 90's. The music was pristinely clean and dynamic, and the surround experience with the DSP modes was really involving, not artificial sounding, while the bass was tight and deep. This was just about one of the best multi channel audio experiences I could remember having at any home. To me there was nothing missing as the surround field was fully enveloping.

CD: Dianne Reeves Never Too Far

While playing the bass track in Track #2 “Never Too Far†with the DSP-A2070 I was pleasantly surprised by how snappy and articulate the upper bass response was. Overall, I found it well controlled and retained excellent the decay properties. The tonal balance was warm and inviting and regardless of how loudly I listened, I never heard the DSP-A2070 amps run out of gas. Stereo separation was about as good as I’ve ever heard, portraying Dianne’s powerful vocals dead center as they should be with plenty of width and depth to the soundstage. The drums had a the requisite pop to them while the saxophones exhibited a nice bite giving you that “live†feeling.

CD: Fourplay Chant

Next up was Fourplay’s “Chant†track which slams with a dynamic kick drum sending wimpy woofers to oblivion and lesser designed amps into hard clipping. As I listened, I requested him to crank up the volume, intoxicated watching those dual woofers of the B&W Diamond 800's flex in and out as the Yamaha pumped pure unadulterated power into them. It was as if Yamaha was convincing me of the flagship status of this receiver as it was able to power those large floor-standers and the four effect speakers without any complaint. The Rock Concert & Jazz Club DSP modes sounded brilliant with this track.

----------------------------------------

DSP-A2070 Internal Amplifier Performance

After this audition the DSP-A2070 proved to be a very competent 7.1 channel amplifier. I was a bit concerned with the DSP-A2070 driving such hulking floor standers along with those big full range center speaker. Mind you the four effect speakers were also connected to big full range speakers too, so these 7 speakers was asking a lot from the internal power amp of DSP-A2070.

My concerns were soon subdued after listening to a few two-channel CD's & SACD's since DSP-A2070 belonging to Dolby Pro Logic era accepts stereo channels only. I was in awe that the Yamaha amp was delivering such solid amplification performance typically found in much costlier and bulkier separates. It sounded as good as many high end rigs I have ever listened in the past. I was shocked by the refined and authoritative bass reproduced by those large B&W floor-standers when driven by the DSP-A2070's internal amps in stereo mode. All of the subtleties and nuances were equally conveyed, demonstrating a very low noise floor and excellent linearity. Granting the fact the Krell separates did yield a bit more slam and dynamics when driven to the limits of comfortable listening levels, but the DSP-A2070 never sounded bright or fatiguing to me like many other receivers typically do.

Channel separation from a two channel audio input was excellent and tonal consistency and dynamics was also impressive when all the seven speakers began to play with different DSP modes.Even pushed very hard and those seven individual full range speakers blasting out, I cannot hear the DSP-A2070 amp run out of gas. May be it is due to the amazing 2.0db dynamic headroom this amp comes with.

In different DSP modes like Rock Concert & Jazz Club for music and Movie Theater & Concert Video for movies the DSP-A2070 amazingly did a bang up job at turning the room into a surround sound live concert or real movie theater.

Even though it was using a quite obsolete Dolby Pro Logic technology to be used for movies, I never felt out of place while watching movies and the overwhelming power from the internal amps was just phenomenl. It just showed to me how advanced the Yamaha DSP modes where back in 1993.

 

[RishiGuru]

Insight to Yamaha's Digital Sound Field Processing (DSP) Technology

After acquiring this DSP-A2070 amplifier I became quite interested in knowing Yamaha's past and especially how this DSP technology came into existence. Digging into the net for a few days I was quite surprised to find out that they manufactured musical instruments since 1887!!! I am dealing with a 125 year old company!

Having this expertise since then, it was from 1970’s onward that they ventured into acoustic designing of concert halls, movie theaters so that accurate sound can be reproduced. Later on they also started custom fittings of audio gear in many famous churches, clubs & even live concert.

Yamaha involved in acoustic designing of concert halls:

While designing the acoustic environment of all these “unique places†Yamaha sound engineers had to study and carry out a lot of tests regarding how their audio equipment should be placed in order to achieve the best possible sonic experience. Test regarding sonic fidelity, echos & reverberation patterns not to mention the liveliness of music as it reaches back of the hall were performed & studied. From all these cumulative experiences they gathered huge amount of raw measurement data in digital format.

Yamaha involved in acoustic designing of churches:

The question now arises as to what is Yamaha DSP?

DSP as we all know stands for “Digital Signal Processingâ€. But in case of Yamaha this stands for “Digital Sound Field Processingâ€. This technology deals in reproducing an audio signal in a way that it mimics the sonic signature i.e. “sound field†of any “unique place†be it concert hall, churches, live performances, clubs, movie theatre, concert video, etc.

This may sound very simple but in order to mimic the “sound field†of any “unique place†at our home, extremely complex algorithms/ software’s were needed and at the same time the hardware needs to be powerful enough to process it in real time. No other audio brand had this feature set back in the 80's. And please do not mix this incredibly complex Yamaha DSP technology with what their competitors were offering back then, those were simple technologies that added some random ambiance & echo’s to the audio signal and nothing more.

Let take an example of a professional high quality movie theater audio system back in the 80's. It generally consisted of a single and very powerful left, center and right speaker behind the screen while having multiple surround speakers engulfing the sitting area. The same surround signal was sent to these multiple surround speakers at a slightly different time creating a sense of spaciousness or liveliness inside the movie theater. And the sound engineers take this factor into account while mixing the sound track of a movie.

Yamaha DSP technology helps to re-create this same "audio experience" aka "sonic signature" aka “sound field†of this “unique place†i.e. movie theater in our home by treating each and every audio frequency of the entire audible frequency range (20~20,000Hz) in real time and making it sound just like the way it sounds in a real professional movie theater in our own home theater. In other words the DSP recreates the “sound field†of a movie theater in our home theater.

In order to achieve this feat the Yamaha engineers used the huge amount of raw digital data that they collected while acoustically designing hundreds of movie theaters around the world. The same principal were followed for other “unique places†like concert halls, concert videos, churches, live concerts, clubs and even TV theaters!!!

But what is this digital data? Actually this data is a sonic signature of each individual audio frequency of the entire audible frequency range (20~20,000Hz) collected in a “unique placeâ€.

This original digital data collected from every “unique place" is stored in the Read Only Memory (ROM) of the Yamaha DSP engine. Now the input audio signal is processed along with the original digital data found in ROM by executing extremely complex algorithms inside the Yamaha DSP engine thus generating a unique audio frequency based correlation data. This correlation data gets stored in the Random Access Memory (RAM) of this engine.

Say if we choose the “Movie Theater†DSP mode, a unique correlation data will be generated after comparing the input audio signal with the original digital data as taken from a real "Movie Theater". This real time and ultra fast process needed truly powerful DSP processors which went on improving with time generating around or over 2 million instructions per second (MIPS)!!!

Later on a final error correction processing is performed on the generated left, center, right & surrounds channels of the correlation data. Now each audio frequency of the entire audible frequency range(20~20,000Hz) should sound like it sounds in an original "sound field" environment, be it concert hall, movie theater, church, etc.

Yamaha also happens to be the only company to have worked with Dolby Laboratories in the early days (70's & 80's) regarding multi channel audio technology. Yamaha was an active technological partner in developing the original four channel “Dolby Stereo†in 1976 having Left, Center, Right, and Rear channels.

Later in 1982 a consumer version of this famous “Dolby Stereo†was released, and to keep the costs down these consumer Dolby Stereo decoders dispensed the center channel and the corresponding logic circuitry as found on the professional decoder as used in movie theaters, but did include the surround delay. To distinguish these decoders from the professional units found in cinemas they were given the name "Dolby Surround" decoders. When a Dolby Surround soundtrack is created, three channels of sound (Left, Right, and Rear) are matrix-encoded into an ordinary stereo (two channel) sound track.

A newer a much improved & more successful consumer version followed in 1987 named as “Dolby Pro Logicâ€. While Dolby Surround dropped the center channel of original Dolby Stereo for cost reasons, the Dolby Pro Logic retained it, and was more true to the original Dolby Stereo as used in professional movie theatres. When a Dolby Pro Logic soundtrack is created, four channels of sound (Left, Center, Right, and Rear) are matrix-encoded into an ordinary stereo (two channel) sound track. The new centre channel is encoded by placing it equally in the left and right channels; the rear channel is encoded using phase shift techniques, typically an out of phase stereo mixdown.

Since Yamaha was involved with Dolby in developing these technologies there was a special DSP mode called “Dolby Surround Enhanced†or “Dolby Pro Logic Enhanced†and was available only on Yamaha receivers. These algorithms were a joint effort of Dolby Labs and Yamaha.

 

[RishiGuru]

Why do we need Yamaha DSP? Isn’t true blue stereo good enough for our home?

Think of a big concert hall.

The size or shape of it, image localization, and echoicness or anechoicness can be appreciated even with our eyes closed. This is because sonic reflections from all directions are heard besides the direct sound emitting from stage (instruments & voices) simultaneously. Our auditory sense can recognize the extent of the hall by the time difference between the direct sound and its reflections, the shape of the hall by the directions of the reflections, and the echoic or anechoic characteristic by the attenuations of the sound.

What really creates the rich, full tones of a live instrument are multiple reflections from the walls of the room. In addition to making the sound "live", these reflections enable us to tell where the player is situated, and the size and shape of the room in which we are sitting. We can even tell whether it is highly reflective, with steel and glass surfaces, or more absorbent - wood panels, carpeting and curtains.

Therefore, simulating the time difference or direction of the reflections and attenuating time may reproduce the sound field of an actual concert hall in our home. As sound produced by performers is reflected by all objects in the hall, it is heard not only from the direct front but also from the sides, rear or ceiling.

In Yamaha DSP terminology “concert hall†will be treated as a sound field. A sound field is defined as the “characteristic sound reflections of a particular placeâ€.

These reflections cannot be reproduced by the conventional stereo channel (2-speaker) system, but require extra speakers to reproduce sound reflection which Yamaha called effect speaker.

Yamaha DSP requires four effect speakers to recreate the sound fields. They are designed to reproduce the realistic sound field experienced in a concert hall in a normal listening room by simulating sound reflections from all directions based on actual measurement data, using extra effect speakers surrounding the listener. Furthermore, the digital signal processing circuit adopted in these units can be used to produce special sound effects, such as combining phase difference signals, changing pitch or changing imaging position periodically.

 

[RishiGuru]

Yamaha's Digital Sound Field Processing Milestone Models(DSP)

Images from the DSP-1 brochure:

Yamaha DSP-1

In 1986, for the first time in audio history Yamaha created a sensation by introducing the Yamaha DSP-1 which supported multi channel speaker arrangement that later give birth to multi channel sound & ‘home theaterâ€. With DSP-1 Yamaha engineers utilized a fraction of the digital data that they collected while designing concert halls, churches, etc into creating a similar simulated “sound fields†in a room. It was the sensation of digital sound in 1986, because for the first time in audio industry a company had mainly focused on multi channel spatial realism.

But then exceptional sonic fidelity had been realized through the digital recording technology used in compact disc players. Now Yamaha had achieved a comparable breakthrough in audio spatial realism by developing one of the significant innovations since stereo, the DSP-1 Digital Sound Field Processor. The DSP-1 was able to recreate the actual acoustical characteristics of 13 live performance environments by digitally reproducing the depth, imaging and spatial of those environments using recorded reverberation and echo patters.

Yamaha used their raw digital data to be processed by a newly developed Yamaha VLSI for DSP-1, which included a high-speed 24-bit X 13-bit multiplier and a 24-bit adder/substarctor, was used to process sonic reflections in real time, while digital signals were processed at a sampling rate of 44.1 kHz by 16-bit linear quantization A/D and D/A converters.

Back in 1986 technical constraints & manufacturing limitations caused the DSP-1 to calculate a fraction of the Yamaha raw digital data since the CPU was not powerful enough to calculate the huge data on real time. To provide an analogy the sound effects was more or less like the 128kbps mp3 music encoding that just barely makes the audio frequency spectrum with a good amount of loss in detailing!!! But still it was a quantum leap in audio industry back in 1986.

Yamaha’s Digital Sound Field Processing (DSP) consists of two main categories. One concept is to enhance music listening and creating realism that mimics the sound effects as found & felt in concert halls, churches, clubs, etc. The listener feels like he is listening to a live concert environment in his living room. It is quite different from current 5.1 or 7.1 formats, since here the receivers just get the pre processed eight channel sound from the source DVD and provide to the eight channels with no internal processing, while for DSP units like DSP-1 accepts a stereo signal & processes it with its dedicated central processing unit (CPU) in real time and provided the six channel output with its “Sound Field†effects.

DSP units try to recreate a concert hall experience in a room just like when stereo equipment is played live in a concert hall. More like concert hall stereo experience. And truly I am staring to like this live experience thing!!! Yamaha provided complex parameters to end users like effect trim, delay, room size, initial delay, etc which can be adjusted from the DSP unit remote control in order to customize for specific requirements of the owners room size & its characteristics. These parameters are quite complex and can take you ages to understand.

The second concept is in using the data measured in reality they do not exist and create a sound space to enjoy & enhance immersive movies experience known as "CINEMA DSP". So you get filed effects like Movie Theater, concert video, TV Theater also in this DSP units.

Yamaha DSP-100

As said before while the DSP-1 could barely make these sound effects, Yamaha engineers started concentrating on improving the DSP unit’s CPU processing power in order to process more and more of Yamaha’s property digital data. Later came models like DSP-100 with significant improvement in the “sound field†effects with much better processing power from its DSP unit. In analogy DSP-100 was like the 256 kbps mp3 version of music encoding, with much more detailing & accurate in recreating the “Sound Fields†than the previous 128kbps DSP-1 version.

The original DSP-1 & DSP-100 used to process only six channels instead of standard seven since it lacked the center channel. Center channel was later added in the next DSP models. DSP-1 units did not even had a volume controller or a integrated amp module, so separate 6 channel master volume controller plus stereo power amp for the main stereo outputs plus a four channel amplifier for the four effect speakers had to be used with it. DSP-100 included the 6 channel master volume controller with it.

Yamaha DSP-A1000

It was in 1990 that Yamaha realized the separate route of DSP unit + master volume controller + stereo power amp for main stereo speakers + 5 channel power amp for effect speakers were just too cumbersome to market and hence amalgamated all these units into a single piece of sonic brilliance, which came to be known as the Yamaha DSP-A1000 weighing a monstrous 20 kg and costing a whopping $2000. The DSP-A1000 had even more processing power than DSP-100 and was a favorite among many people who owned this seven channel amplifier. In analogy DSP-A1000 was like a 320kbps mp3 version and was truly good in creating detailed & perfect “sound field†effects with its powerful DSP unit.

After a great success of DSP-A1000 the Yamaha engineers concentrated wholly on the DSP processing unit & its processing power alone for the next three years. In 1993 when the DSP-A2070 was released it looked identical to DSP-A1000. The only difference from outside appearance was the numbering on the faceplate!!!

Yamaha DSP-A2070 & Remote Control

While DSP-A2070 retained the stellar power supply & power amplifier modules of DSP-A1000, this time around the DSP unit was three times more powerful than DSP-A1000!!! In analogy it was like the FLAC version of music encoding with superb, picture perfect & almost real “sound field†effects. Back in 1993, the $2000, 21kg, 7 channel , Yamaha DSP-A2070 was their venerable flagship.

With the DSP-A2070 the huge amount of data that Yamaha collected while designing concert halls were properly utilized, and the engineers was so happy with the imaging & detailing of the DSP-A2070 “Sound Field Processing†that in there next model released in 1995 the DSP-A3090 had the same DSP music processing of DSP-A2070, while the whole new concept of Cinema DSP dedicated to movies & not music was ventured into. DSP-A3090 was basically a DSP-A2070 unit with some additional memory to compensate for the "Tri-Field Processing" which was added to Dolby AC-3 surrounds (later known as Dolby Digital). Otherwise, features were virtually identical to the DSP-A2070.

Yamaha DSP-A2070's DSP unit

I have minutely studied the DSP unit of my DSP-A2070 as shown above and became quite impressed with their work. In plain words what you are looking at at is a tiny computer with dedicated CPU, RAM, bus, cache memory, storage memory, memory bus.... Pretty impressive work back in 1993 using Cirrus Logic ADC's and Burr Brown DAC's.

Mind you both A1000 & A2070 had the option for the main left & right stereo speaker channels to pass through this DSP unit having the added "sound filed" effects and A/D to D/A conversions, or to bypass this DSP unit and remain pure analog or in other words "pure stereo" mode. This can be done with the "Front Mix" switch located a the back of the amp in off position.

Amazingly while Yamaha started designing concert halls from 1970, it took them full 23 years to fulfill the desired results that the engineers wanted from there DSP amplifiers. I will later provide the detailed technical analysis of this module.

@Update : I am currently using the DSP-A2070 in a six speakers configuration(no center channel still) and really enjoying the Digital Sound Field Processing that this amp comes laden with. By heart I am purist, but when the mood is right I really start enjoing these DSP modes!!!

My favorites are Concert Hall1, Church, Rock Concert & Jazz Club.

 

[ronnie_gogs]

It was nice to read about your experience and how you are enjoying this amplifier.... Congrats although its already a few months since you have it...

 

[Jonskitch]

After reading this information provided by rishguru. I ended up aquiring all 3 the dsp-a1000, 2070 and 3090. All costing lest than RS10,000 on Ebay. Just wanted to see how it would compare to my M&F A5. Remember I am not ineterested in its HC - this is dated. I am only looking at the 2 channel side. The good news is that they all sound positive. They sound lot bigger than there watts rated (80W pc). The sound is big bold and very smooth very like NAD amps - but slightly more detailed. When compared to my A5 the sq lived upto it. Out of the 3 ; the DSP-1000 is the best for audio. I will continue with further testing and keep you updated.

 

[Jonskitch]

After further testing all of the units go far beyond there rated power. It simply blows away my Quad 303 pre-amp and 404 power amp - not enough reserve. Audiolab 8000a, Marantz 7200 KI, Cyrus 8Vs2 with PSX and Finally Musical fidelity B1 - All these amps mentioned could not produced enough slam to satisfy my needs but however all the yammys produced earth shattering bass which was bit of a surprise - this is probably down to that titanic power supply connected via those large capacitors. Not even once the yammys sounded out of steam you could basically turn it pass 11 and it kept on going - was scared after. The sound is nice and silky smooth with good authority especially on the bass side. Next will compare with my M & F A5.

 

[Jonskitch]

Yamaha A1000, 2070 and 3090 - which one?

The story continues with these 3 Yamaha’s that I recently acquired from eBay. All 3 Yamaha’s sounded great but I found that especially the 2070 and A1000 had even more headroom than 3090. Between 2070 and A1000 there was very little differences but I noticed A1000 was touch more refined which suited to my taste but this can be subjective. They all had similar characteristics; warm, smooth, big, bold, dark, energetic approach very like valve sound which I particular fancied .

Amps generated - front channels only

A1000 - 149 amp continuous peaked at 190 amps

A2070 - 143 amp continuous peaked at 184 amps

A3090 - 127 amp continuous peaked at 167 amps.
Current ratings are high, so in respect all 3 Yamahas should able to drive even difficult loads. Since A1000 had the biggest drive I continued with my research around this amp.

Musical Fidelity A5 versus A1000 - Battle of the titans.

Sound Quality

Both amps had huge presentation that could fill a medium to large room. Although both amps

had immense drive but their sound properties were some what quite different. The A5 was more open but less wide and had solid state feel While the A1000 was more neutral and natural which leaned more towards a tube like feel. The A1000 had more drive in low frequencies without masking mids and highs. The A5 was quite even throughout the spectrum but occasionally lost focus on highs - strange but through. The Yamaha felt more relaxing and pleasing to the ears and yet it was opposite with A5. However they both performed well in all types of music and handled complex pieces with ease. The timing, dynamics, and clarity on both amps were Excellent - I could not separate them. My heart goes towards Yamaha because it had more civil and sensible approach.

Power and drive

The A5 (250 watts per channel) on paper seemed a lot more powerful than A1000(80 watts per channel) but this wasn’t the case in reality. I had this funny feeling that Yamaha only based this calculation on average rating but the huge one box solution had lot more muscle under that bonnet. My guess would be that A1000 was at least hitting in the peaks of around 160 watts per channel and wasn’t far behind the A5. I still felt that the bass was deeper, tighter and fuller on A1000 than the A5 but on the other hand the A5 had the extra drive which put A1000 to its limits. Nonetheless, the Yamaha had enough guts and reserve to even challenge the mighty A5 in the power department. The A5 carries the extra current and charge which beats the A1000 in this area but not by much.

Damping factor under test

A5 - better than 130

A1000 - better than 137

Technology

A5 is a pure audio amp that is based on dual mono technology. A clever design.

A1000 is overly engineered AV amp that performs quite well with both audio and AV.

Conclusion

Both amps performed well in their own rights. But however Yamaha A-1000 will never be recognised as a true audio amp as the product was purely designed for HC. The logo “AV†will put many audiophiles’ off and in no way would have this at the heart of the centre. For mass market this would be an ideal amp as this would cream many sub £1000 (audiophile standard) amps. On eBay this can be picked up for merely Rs5000. Highly recommended.

Equipments used:

Marantz CD94 mkII

Jamo oriel speakers

kimber speaker cables

Wireworld interconnects

Box standard power cable (A5) as A1000 is equipped with captive power lead.

 

[Jonskitch]

After reading this information provided by rishguru. I ended up aquiring all 3; the dsp-a1000, 2070 and 3090. All costing less than £200 on Ebay. Just wanted to see how it would compare to my M&F A5. Remember I am not ineterested in its HC - this is dated. I am only looking at the 2 channel side. The good news is that they all sounded positive. The sound was lot bigger than there watts rated (80W pc). Delivery was big bold and very smooth like NAD amps - but slightly more detailed. When compared to my A5 the sq lived upto it. Out of the 3 ; the DSP-1000 is the best for audio. I will continue with further testing and keep you updated.

After further testing all of the units go far beyond there rated [color=blue !important][font=inherit !important][color=blue !important][font=inherit !important]power[/font][/font][/color][/color]. It simply blows away my Quad 303 pre-amp and 404 power amp - not enough reserve. Audiolab 8000a, Marantz 7200 KI, Cyrus 8Vs2 with PSX and Finally Musical fidelity B1 - All these amps mentioned (previously owned)could not produce enough slam to satisfy my needs but however all the yammys produced earth shattering bass which was bit of a surprise - this is probably down to that titanic power supply connected via those large capacitors. Not even once the yammys sounded out of steam you could basically turn it pass 11 and it kept on going - was scared after. The sound is nice and silky smooth with good authority especially on the bass side. Next will compare with my M & F A5.

[color=blue !important][font=inherit !important][color=blue !important][font=inherit !important]Yamaha[/font][/font][/color][/color] A1000, 2070 and 3090 - which one?

The story continues with these 3 Yamaha’s that I recently acquired from eBay. All 3 Yamaha’s sounded great but I found that especially the 2070 and A1000 had even more headroom than 3090. Between 2070 and A1000 there was very little differences but I noticed A1000 was touch more refined which suited to my taste but this can be subjective. They all had similar characteristics; warm, smooth, big, bold, dark, energetic approach very like valve sound which I particular fancied .

Amps generated - front channels only

A1000 - 149 amp continuous peaked at 190 amps

A2070 - 143 amp continuous peaked at 184 amps

A3090 - 127 amp continuous peaked at 167 amps.

Current ratings are high, so in respect all 3 Yamahas should able to drive even difficult loads. Since A1000 had the biggest drive I continued with my research around this amp.

Musical Fidelity A5 versus A1000 - Battle of the titans.

Sound Quality

Both amps had huge presentation that could fill a medium to large room. Although both amps

had immense drive but their sound properties were some what quite different. The A5 was more open but less wide and had solid state feel While the A1000 was more neutral and natural which leaned more towards a tube like feel. The A1000 had more drive in low frequencies without masking mids and highs. The A5 was quite even throughout the spectrum but occasionally lost focus on highs - strange but through. The Yamaha felt more relaxing and pleasing to the ears and yet it was opposite with A5. However they both performed well in all types of music and handled complex pieces with ease. The timing, dynamics, and clarity on both amps were Excellent - I could not separate them. My heart goes towards Yamaha because it had more civil and sensible approach.

Power and drive

The A5 (250 watts per channel) on paper seemed a lot more powerful than A1000(80 watts per channel) but this wasn’t the case in reality. I had this funny feeling that Yamaha only based this calculation on average rating but the huge one box solution had lot more muscle under that bonnet. My guess would be that A1000 was at least hitting in the peaks of around 160 watts per channel and wasn’t far behind the A5. I still felt that the bass was deeper, tighter and fuller on A1000 than the A5 but on the other hand the A5 had the extra drive which put A1000 to its limits. Nonetheless, the Yamaha had enough guts and reserve to even challenge the mighty A5 in the power department. The A5 carries the extra current and charge which beats the A1000 in this area but not by much.

Damping factor under test

A5 - better than 130

A1000 - better than 137

Technology

A5 is a pure audio amp that is based on dual mono technology. A clever design.

A1000 is over- engineered AV amp that performs quite well with both audio and AV.

Conclusion

Both amps performed well in their own rights. But however Yamaha A-1000 will never be recognised as a true audio amp as the product was purely designed for HC. The logo “AV†will put many audiophiles’ off and in no way would have this at the heart of the centre. For mass market this would be an ideal amp as this would cream many sub £1000 (audiophile standard) amps. On eBay this can be picked up for merely £50. Highly recommended.

Equipments used:

Marantz CD94 mkII

Jamo oriel speakers

kimber speaker cables

Wireworld interconnects

Box standard power cable (A5) as A1000 is equipped with captive power lead.

 

[infiniti52]

I have a yamaha dsp 2070. I would like to eliminate the dsp boards and just leave the amp and preamp in the chassis. Can this be done and how and has anyone attempted it. I know you can bypass the pre or the amp.

thx

 

[RishiGuru]

After six months of acquiring this old 7.1 channel Yamaha DSP-A2070 integrated amplifier out of sheer curiosity I opened the cabinet of this huge amplifier in my off time and did some nooby analysis all by myself. Please do pardon me if there is any error in my analysis.

After about two days of tinkering with this amp plus reading the entire service manual, I reached to the conclusion that the power output claims of this amp and all those of 80's & 90's era where more truthful to their actual output capabilities than those of todays. Let me share the findings with this internal shot of DSP-A2070:

Back in 1993 Yamaha advertised this DSP-A2070 as their Top Of The Line[TOTL] amp costing $2000. On release it immediately own the coveted EISA award for the best performing home theater system. It is capable to provide 100 watts @ 6 ohms each for the main left, main right & center channels while only 26 watts was provided for the rest four channels.

One has to remember this total of max of 100X3 + 26X4 = 404 watts @ 6 ohms is available through out the 20Hz to 20KHz audio frequency range having THD levels less than 0.015%. When a company rates their amp say at 1kHz, this usually means a full bandwidth(20Hz-20kHz) measurement will be about 15-20% lower. Also keep in mind this amp weighs a hefty 21 kilos.

The Power Supply

DSP-A2070 consists of two discrete power supply units designed to satisfy two entirely different requirements.

The Smaller Power Supply

The smaller one is marked in white rectangle(pic above) situated at the extreme right bottom corner, being dedicated to power the pre-amplifer module, the Digital Signal Processing(DSP) circuits, amp's protection circuits & all the LED's.

The Bigger Power Supply

The second power supply unit consist of an humongous EI core step down transformer which can be found in the violet rectangle(pic above) being completely dedicated to the power amplifier section alone and are assisted with huge power capacitors(the biggest I have ever seen) as shown in sky blue & blue rectangles(pic above).

This transformer is over 5 inches tall, 6 inches wide and is rated at 800VA or 800 watts weighing nearly 8.5 kilos alone. I have never seen such a huge transformer in an reciever and if I compare the whole of the currently available Yamaha RX-V471, 5.1 channel receiver with 105W (6ohms, 0.9% THD) (1kHz, 1ch driven) rated power output claim, weighs a mere 8.2 kilos. So, as I found out the DSP-A2070 transformer alone weighs more than many new recievers as found today.

This transformer is assisted with four power capacitors. Those bigger pair of 4 inch tall lug type capacitors(clamped with the frame) shown by the sky blue rectangle(pic above) on the upper top corner are rated 22,000uF each and takes care of main left, main right & center speakers. This means an additional 44,000 joules of energy are stored and are readily available with the power supply in order to handle the dynamic peaks of music. Equates to 44000/3 =~ 15,000uF per channel rated at 100 watts each.

To provide an analogy my Norge 1000 stereo amp rated at 125 watts per channel uses just 9,400uF capacitance per channel. DSP-A2070 have almost two times the capacitance of Norge in order to handle the dynamic peaks per main left, main right & center speakers.

Coming to the rectangle in blue(pic above) I find the other pair of capacitors rated at 8,200uF each being dedicated to the four effect speaker channels. This means an additional 16,400 joules of energy are stored and are readily available with the power supply in order to handle the dynamic peaks of music. So we have 16,400uF capacitance for these 26X4=104 watts.

So, I ended up with a respectable 800 watts transformer and 60,400uF of capacitance dedicated to help the transformer if ever it runs out of juice at extreme high volume levels. Yamaha claims just 404 watts from all these 7 channels.

The Power Transistors

For the Main left, Main right & Center channels

The power amplifier module of thie DSP-A2070 uses discrete/solid state technology. It uses a pair of Toshiba 2SA1302/2SC3281 power transistors in push pull mode for each of its right, left & center channels. These transistors are marked in light brown rectangles(pic above) in pairs.

Looking at their spec sheet I found out each of these transistor pairs are capable to produce 150 watts of peak dissipation thus easily pumping out a genuine 100 watts of continuous power without crossing the SOA limit. Considering the fact that these transistors have roughly 50% efficiency(actually they are more efficient) , each of these pairs will be requiring at around 200 watts of power from the power supply i order to produce 100 watts of power for each channel while the rest 100 watts being dissipated/lost as heat.

Summing up these 3 pairs of transistors for the right, left & center channel will require 200X3=600 watts of power from the power supply to produce 300 watts of max power in total which equates to 300/3 = 100 watts per left, right & center channel, all channels being driven simultaneously.

For the Four Effect Channels

Yamaha used a pair of Sanken 2SA1726/2SC4512 power transistors in push pull mode for each of the four effect speaker channels shown in the brown rectangle(pic above). Each of these transistor pairs can easily pump out 26 watts of continiuous power without even comming close to their SOA limit. Again if we consider these transistors having roughly 50% efficiency, each pair will require 52 watts of power from the power supply in order to produce 26 watts of power to each of the channels, the rest 26 watts being dissipated as heat.

Four pairs of transistors for thsee four channels will require 52X4=208 watts of power from the power supply in order to produce 104 watts of max power in total, which equates to 104/4 = 26 watts for each of these four channels all being driven simultaneously.

The Heat Sinks

Even before I consider this amp is truly capable to deliver a genuine 404 watts of continious power, I had to consider how the rest 404 watts of total heat generated from all these 14 power transistors can be dissipated properly. Looking at the dual row of heatsinks, each above 4 inch tall and nearly 12 inches long I came to the conclusion that this amp must be producing a lot heat, and since it produces a lot of heat a equal amount of lot of power is produced and provided to the speakers.

Calculations

Total continuous power providing capability of the power supply = 800 watts (excluding the power capacitors)

Total power requirement from the power supply in order to produce the manufacturer claimed 404 watts = 600 + 208 = 808 watts.

At least from a technical point of view it seems this DSP-A2070 meets the demand of its power amp section in full measure and are actually capable to deliver a true 404 watts of continuous power output, throughout the entire audio bandwidth (20Hz~20kHz) @ just 0.015% THD with all the seven channels being driven simultaneously.

Until now I have not even considered the reserved 60,400 joules of capacitance of those power capacitors waiting to lurk whenever & ever if there is more need of power. The outcome with this amount of dedicated capacitance is that the DSP-A2070 comes with full 2.0dB of dynamic headroom @ 6 ohms. Very few TOTL AVR's can ever match this figure.

This means you will never feel the amp is running out of juice and will provide 404 watts of steady continuous power @ 6 ohms with all channels being driven simultaneously and in extreme circumstances(say full volume) will jump up to 600 watts for a moment (without even considering the transformer's internal capacitance) to handle transient peaks of a complicated music composition when heard in full blast.

IMHO the points to consider about an amp's real power output capabilities are :

1) The weight of the amplifier/ AVR in question. Heavier means more power.

2) The size & weight of the transformer. Bigger & heavier means more power.

3) The amount of capacitance available from the power capacitors. More is better for better dynamic headroom.

4) The heat sink size. Bigger means more power.

5) The power transistors in use & their max power output capabilities.

---------------------------------------

Please feel free to add your own inputs.

 

[jl4761]

How's it going everyone? My name is John and this is my first post here on the forum. I own a Yamaha DSP-A2070 Digital Sound Field Processing Amplifier, I am the original owner that paid over $2000.00 for it. I have had years of enjoyment with my unit to this very day.

Recently, I have been experiencing a problem with my unit that just started last week. My unit cuts off with no warning, I turn it back on and 3 seconds later, it cuts off again. It keeps happening repeatedly over and over again. I hope that many of you can advise me as to what the problem is so I can get it repaired (If possible). I am looking forward to all of your responses, take care.