Close Advises

Close Amplifiers

Close Apogee

Close Awesome system

Close CD Players

Close DAC

Close Dematerialization

Close Discs-Music

Close Fascinating components

Close Fidetech

Close Headphones

Close Historical

Close Interconnect cables

Close Loudspeakers

Close Optimization

Close Power cable

Close Preamplifiers

Close Receivers

Close Reference systems

Close Stereophile

Close Threshold

Close Tube amp list

Close Tubes and others

Close Tuners

Close Turntables


Close Accessories

Close Connectors

Close Interconnect cables

Close Power cable

Close Repairing your equipment

Close Speakers cables

Close Threshold amps optimization

To receive news about this website, consider subscribing to our Newsletter.
27 Subscribers
Webmaster - Infos
DAC - Theta DSPro Generation Va

THETA DSPro Generation V-a

A Prince amongst the DACs

→ Updated on March 20th, 2016 (feedback from Dave REICH)


The THETA owner is Mr Neil SINCLAIR, his Chied Engineer is Dave REICH. If you do not know them, it means that you have forgoten the Dayton WRIGHT products (pannels) and the Classe Audio products such as the famous DR2 and DR3-VHC reviewed on our site.
Dave REICH has sent us his feedback regarding our review of the CLASSE AUDIO DR3-VHC, and you can read it at the end of the CLASSE AUDIO DR3-VHC review.
As always, any brands needs a genius to emerge amongst all the other audio brands : Mr REICH is one of them.
He gave us the very famous THETA Gen V-a that came after the previous generations I, II and III. The gen IV has never been issued.
The brand logo is still easily identified:


The THETA company is still in the Business :

Theta Digital 1749 Chapin Road  Montebello  CA  90640  USA
phone: +1 (323) 278-0001 | email:


II-DAC THETA DSPro Generation V-a.

This DAC is not a recent one : it was introduced on the market in 1992. Its design was the state of the art at this time, and it still belongs to the very best design available more than 20 years after. The reason is simple: based on our listening experience, the very best DACs on the market share the same common approach using a few DSP chips (instead of a usual receiver like the CS8412 / CS 8414 / CS 8416 / DIR 9001...) to prepare the digital signal BEFORE sending it to the conversion chips.

The facts are there: this part of signal processing before the conversion itself is much more important than the quality of the conversion chips, and much more important than the number of bits of the conversion chips.

Any oversampling method introduces artifacts in the musical reproduction and the approach using DSPs before the data conversion is, by far, the best one.

So why is it not more common in the high end, and why do we see (instead) a lot of marketing around the 4x, 8x,... oversampling methods, around 32 bits conversion chips, etc ?

Simply because this approach using DSPs before the conversion step is much more costly than any other one, and requires a lot of digital expertise to design the filtering program (to be implemented in the DSPs).

The other reference brand in the state of the art DACs is WADIA, which was the first to indroduce this approach using DSPs. The WADIA 9 (its review will be published soon) for example uses 2 x AT&T 3210 DSPs and 1x XILINX

This THETA uses 3 MOTOROLA 56001 DSPs. There is no On/Off switch on the THETA, so the unit remains On permanently. A relatively bad thing is that the unit operates in class A (this is good !) and so generates a lot of heat on its right side : even with the radiators the heat looks a bit high...


The version V-a supports the 96kHz format, but the optical input was an option.


Here is the front view:



and the rear view:


and the most interesting internal view, with the digital section on the left and the analog one on the right:



The power supply transformers are located on the bottom of the unit:



There is no remote control with this DAC.



Our listening configuration remains the same in order to provide you with a stable base of compparison, we have used the reference system #2 for this review:





During the first minutes, we did not notice anything particuler : the DAC requires a few minutes to reach its optimal temperature.

Ater this period, the THETA musical qualities clearly appear: it does not need 24 or 48 hours to reach its optimum, contrarily to the WADIA 9 (a true reference DAC) that requires 1 week to reach its best...

The highs are extremely good, detailled, never agressive but clearly vibrant. The bass is impressive, the depth is in the same league.

This DAC delivers the music with ease, from the botttom end to the top highs : do not take your car to go to the concert, with the DIVA loudspeaker like mine, the concert is at home..

The form factor is relatively small, not impressive, but the sound that it delivers is really impressive: it is clearly one of the very best DAC available on the market, and I am in love with it.

Once again, we regret that this kind of well designed , well made products are no longer manufactured dus to the cost savings race. Probably the big dCS or WADIA DACs are in the same league nowdays, but you do not need all the fingers of your hand to count the competitors...

For your information, the engineers that have designed this THETA unit are therefore working for a company named SCHIIT Audio, and have issued a model named "Yggdrasil" on the market, using an Analog Devices AD5791 chip, but we do not know how is designed the filtering section before the conversion. Maybe it would be a good idea to lesson to it, just in case they have used a similar genius design...



This THETAD DSP Gen V-a is an exception in the world of DACs. It offers an truly exceptional musical performance from top to bottom, an exceptional depth on every style of music. This level of musical quality is reached by very few DACs, similar to the number of fingers you have on one of your hand...



  • perfect balance from top to bottom
  • the bass offers spped and beauty
  • it has a lovely analogic style of musicality
  • it supports 96kHz


  • it generates to much heat
  • there is not AT&T optical input (it was an option)
  • no more aftersale service (except on very very few high skilled technicians....)
  • may (not systematically) need a replacement of the electrolytic capacitors
  • its price remains high, even after more than 20 years: > 2 000€







Creation date : 30/08/2015 @ 18:08
Last update : 20/03/2016 @ 16:57
Category : DAC
Page read 1201 times

Print the article Print the article

Reactions to this article

Nobody gave a comment yet.
Be the first to do so!

Members List Members : 708

Your nickname:


[ Password lost ? ]

[ Become a member ]

  Member online:
  Anonymous online: 24

Total visits Total visits: 0  




   visitors online

^ Top ^