Bringing a vintage DAC into a new age?

[Multiplex]

I know it's old, but I still love it...

I have a Theta DS-Pro Generation V-a DAC from the late 90's. It's the "updated" one with the 3rd LED for HDCD and balanced XLR outs. Unfortunately, having picked this up second hand with no documentation, I really don't know much about it's capabilities. I've spent the last four years using it with a NAK CD Player 2 and an Integra changer. It sounds great for that. But, like many of us here, I have taken an interest in hi-res streaming.

First of all, does anyone know the maximum bit/sample rate of this DAC? Looking around online, I've found very conflicting information. I've seen 16/44.1, 20/48, and even mention of a 24/96 upgrade that may have once existed.

Is there a good way to use this DAC with hi-res files, even if the sample rate has to be limited to the DAC's capabilities? If so, what is the best device to convert USB to digital coaxial?

Amazon has a fun looking little toy for $21 that will accept a USB input and feed out to a max 48khz digital coaxial. Might be good enough, but I worry it might be junky and jittery. They also have a $65 device that is capable of higher sample rates, but would there really be an advantage with such a limited DAC? I prefer not spending a ton of money on this project. After all, this thing is old, and could potentially fail at any time. I don't even know who could repair it if it did. Theta doesn't touch them anymore. But, I'd like to use it for as long as it will let me.

Assuming I get one of these adaptors, will I have issues downconverting "master quality" files to work with this tired old beast?

 

[dewdude]

The DAC appears to be capable of up to 48khz/20 bit.

If you want to do "HD" audio, it will have to be downconverted. 20 bits aren't a standard rate used in PC audio; it's basically in the middle of 16 and 24 bits.

The overall quality will depend on the SPDIF adapter and quality of the down conversions of the high res audio.

 

[SterlingOne]

I know it's old, but I still love it...

I have a Theta DS-Pro Generation V-a DAC from the late 90's. It's the "updated" one with the 3rd LED for HDCD and balanced XLR outs. Unfortunately, having picked this up second hand with no documentation, I really don't know much about it's capabilities. I've spent the last four years using it with a NAK CD Player 2 and an Integra changer. It sounds great for that. But, like many of us here, I have taken an interest in hi-res streaming.

First of all, does anyone know the maximum bit/sample rate of this DAC? Looking around online, I've found very conflicting information. I've seen 16/44.1, 20/48, and even mention of a 24/96 upgrade that may have once existed.

Is there a good way to use this DAC with hi-res files, even if the sample rate has to be limited to the DAC's capabilities? If so, what is the best device to convert USB to digital coaxial?

Amazon has a fun looking little toy for $21 that will accept a USB input and feed out to a max 48khz digital coaxial. Might be good enough, but I worry it might be junky and jittery. They also have a $65 device that is capable of higher sample rates, but would there really be an advantage with such a limited DAC? I prefer not spending a ton of money on this project. After all, this thing is old, and could potentially fail at any time. I don't even know who could repair it if it did. Theta doesn't touch them anymore. But, I'd like to use it for as long as it will let me.

Assuming I get one of these adaptors, will I have issues downconverting "master quality" files to work with this tired old beast?

I've got a DAC in my Sony PCM-7010F that's to die for but absolutely no means to incorporate it into a device for listening to today's streams, unless I record those streams to the unit, which I have indeed done, since it sounds so good.

 

[Multiplex]

The DAC appears to be capable of up to 48khz/20 bit.

If you want to do "HD" audio, it will have to be downconverted. 20 bits aren't a standard rate used in PC audio; it's basically in the middle of 16 and 24 bits.

The overall quality will depend on the SPDIF adapter and quality of the down conversions of the high res audio.

Thanks for the reply. That kind of seemed to be the consensus when I was researching the Gen Va. Not sure how to tackle the bit depth thing. Downconverting to 16 would obviously work, but it would be a pity to not be able to use the DAC to it's full potential. I have not really messed with streaming services or settings beyond plain compressed Amazon or Spotify, and neither through this DAC. Will there be a way to convert to 20 bit, or is that just too oddball?

 

[Multiplex]

I've got a DAC in my Sony PCM-7010F that's to die for but absolutely no means to incorporate it into a device for listening to today's streams, unless I record those streams to the unit, which I have indeed done, since it sounds so good.

Those Sonys are nice.

I hate it when a good DAC is imprisoned in a limited device. The digital rig I used before the Theta was a Denon DVD2930CI DVD player. Killer sounding internal DAC! Nothing but transport problems though, and no other inputs. I had one completely die on me, so I found a second one for fairly cheap. I got a couple good years out of it before it started skipping tracks and not reading certain discs. I do like the Theta better, but the Denons would've been quite useful, if only they could have been used as slave DACs. Still probably wouldn't hack it for streaming, though.

 

[dewdude]

Thanks for the reply. That kind of seemed to be the consensus when I was researching the Gen Va. Not sure how to tackle the bit depth thing. Downconverting to 16 would obviously work, but it would be a pity to not be able to use the DAC to it's full potential. I have not really messed with streaming services or settings beyond plain compressed Amazon or Spotify, and neither through this DAC. Will there be a way to convert to 20 bit, or is that just too oddball?

It's odd-ball alright. Like I'm sure somehow with the multitude of software I've got, I could get something down to 20-bit; but my editors and such are going to want to store it as 24-bit. There's some extended options and stuff I'll admit I've never looked at. I've never had a reason to stream at 20-bit.

That being said, SPDIF was designed to carry 20-bit audio...but can carry 16 by padding and support for 24 has kinda become a de-facto standard. There's also the issue with operating systems, drivers, and other "behind-the-scenes" stuff likes to work with standard depths like 16 and 24.

 

[xero-D-hero]

That's a really good Redbook DAC,so I would'nt go messing with it too much myself.
I'd just accept that for 16/44.1 that DAC is about as good as it gets.
And yeah you can throw in HDCD content if you really want to.
But a LOT of us out here are plenty happy to slog along listening to only Redbook CD's.

That DAC uses 4x PCM63P-K which Mike Moffat has publicly stated is (in his opinion) the best DAC chip ever made.
(FWIW Mike Moffat is the guy who designed the Theta DACs and he is also the current co-owner of Schiit)

If I had enough inputs I'd just run a seperate "modern" DAC for streaming and keep this one strictly for Redbook/HDCD use.
I'm willing to bet this DAC is gonna sound excellent in many respects,so I would'nt be surprised if you still listened to it a lot.

Me,I'm a big fan of the PCM63,and currently I own two Parasound D/AC-1000 and love 'em.
Now those (D/AC-1000 & D/AC-1500) CAN be upgraded to accept 24/96 via the audiotuning.com kits.
But those Parasound D/ACs use different reciever chips vs. this Theta DAC.

>>> ADDENDUM <<<

and even mention of a 24/96 upgrade that may have once existed.

Maybe call (or Email) Mike Moffat over @ Schiit and ask him about that deal.
Seeing that he designed that Theta DAC he'd be the one to know about that situation and my guess is he's still pretty proud of that DAC.
So yeah he may be more than willing to help you with info,I mean it never hurts to ask,right?

Anyhow yeah I love the PCM63 for Redbook material,and I only listen to Redbook,so for me it's largely a non-issue.

But I digress,just some food for thought.

Bret P.

 

[Multiplex]

That's a really good Redbook DAC,so I would'nt go messing with it too much myself.
I'd just accept that for 16/44.1 that DAC is about as good as it gets.
And yeah you can throw in HDCD content if you really want to.
But a LOT of us out here are plenty happy to slog along listening to only Redbook CD's.

That DAC uses 4x PCM63P-K which Mike Moffat has publicly stated is (in his opinion) the best DAC chip ever made.
(FWIW Mike Moffat is the guy who designed the Theta DACs and he is also the current co-owner of Schiit)

If I had enough inputs I'd just run a seperate "modern" DAC for streaming and keep this one strictly for Redbook/HDCD use.
I'm willing to bet this DAC is gonna sound excellent in many respects,so I would'nt be surprised if you still listened to it a lot.

Me,I'm a big fan of the PCM63,and currently I own two Parasound D/AC-1000 and love 'em.
Now those (D/AC-1000 & D/AC-1500) CAN be upgraded to accept 24/96 via the audiotuning.com kits.
But those Parasound D/ACs use different reciever chips vs. this Theta DAC.

>>> ADDENDUM <<<

Maybe call (or Email) Mike Moffat over @ Schiit and ask him about that deal.
Seeing that he designed that Theta DAC he'd be the one to know about that situation and my guess is he's still pretty proud of that DAC.
So yeah he may be more than willing to help you with info,I mean it never hurts to ask,right?

Anyhow yeah I love the PCM63 for Redbook material,and I only listen to Redbook,so for me it's largely a non-issue.

But I digress,just some food for thought.

Bret P.

That is a very good thought about maybe trying to contact Mike Moffat... After all, Theta offers no support for these now. Not even specs or online manuals. I might have to look into that.

The Theta truly sounds great, though. No grain, no grit, just smooth. It's warm, yet detailed and dynamic, without the fatigue I'm used to from my other digital sources. Once it went in the rack, it never left. Prior to it's arrival I was spinning vinyl almost exclusively. Guess I still mostly do, but this thing brought CDs back into the picture pretty big time. In fact, this has inspired me to find tons of decent dirt-cheap CDs at thrift stores because of their current "uncoolness factor." At the same time, vinyl has gone through the roof. CD hunting has been quite enjoyable!

I've thought about investing in a higher-end transport too, but I'm not so sure now. Fewer and fewer CDs are being pressed. Some material will probably never make it to CD in the future, and maybe not vinyl either, depending on how long the vinyl revival lasts. The world seems to be moving quickly towards streaming, and I'm thinking that it might be worth joining the party, at least in part. I'll never let go of physical media. I'm not a huge fan of the idea of "renting" media, but I think it'd be foolish for me to dismiss streaming altogether. It's a fun way to find new music I never knew existed. So far, lossy streaming has been great for the car and the back patio, but horrible through the big system.

I thought about investing in a second DAC for hi-res files, which is something I still might do. After all, I really won't be able enjoy the full benefits of hi-res media with the Theta. Trouble is, I really don't have the big bucks to spend. I'll be looking in the budget realm.

I would have to think that there is more to decoding digits than sample rates and bit depth. My Theta weighs as much as a power amplifier, has an absolute killer analog section, rock solid power supply, and first-class components throughout the digital section. I know that time and technology has moved on, but will will a current 3lb sub-$500 DAC compete with the Theta, even having the advantage of high-res files? It certainly wouldn't be a fair fight, considering that Theta was a $6,500 piece in it's heyday. I'd hate to make a fairly large (to me) investment only to find that those 192kHz 24bit files sound inferior to my old silver discs.

That's why I was thinking that the most economical choice at this point might be to try to drag the old Theta into this century. If I can make streaming sound at least as good as my CDs, I feel like I'll be getting somewhere. If I can stream at 48 kHz, I would think they should sound ever-so-slightly better. Maybe I won't even be able to tell. Who knows. Never really noticed much of a diff with HDCD media...

 

[mjw21a]

Personally I'd leave this DAC alone and just keep enjoying it. It's in another league in terms of implementation to my beloved Muji Studio DAC II.

I've found that these older DAC's seem to match or surpass the performance of the best modern units playing DSD content, and when it comes to playback of lower bit rate content there's just no competition what-so-ever.

It may be worthwhile looking to see if there are any electrolytic caps need replacing, and maybe upgrade any output caps though that's as far as I'd go. Maybe addition of a USB input though it would be easier to use a separate interface like a Gustard U12 for this.

 

[SterlingOne]

Interestingly enough, although we've now lived through about 40 years of DAC "upgrades" seems there's still no general acceptance of where the DAC should reside. Residing in a Preamplifier sounds good, but only until a new and improved DAC appears, making the whole preamp obsolete. This makes me yearn for standardization of a DAC socket, which would allow upgrading without need to replace a whole component. Until then the stand alone DAC seems most appropriate. On another note, I've got a lot of DAC redundancy for stereo media pleasure. Thing is, it's a multi-channel world we live in today, so I've now routed my PC's usb drive to my OPPO's 8 channel DAC to be able to enjoy both stereo and multi-channel music.

 

[xero-D-hero]

In terms of a second DAC just for streaming I'd keep it cheap & simple.
Probably something like the Modi3 from Schiit.that would at least cover you up to 24/192 (via USB) for $99.00.
And most agree it to be an excellent "bang for the buck" DAC.
Plus it's small so it's easy to squeeze into almost any rig w/o being too obvious.
That also gives you two additional digital inputs as well (optical & coax).

And if you want to send USB to the Theta yeah there are options for that ranging from affordable to big $$$.
If you hurry up you could get the Schiit Eitr USB-to-coax convertor for $149.00 before they stop selling them.
So that might be worth looking into as well.

Anyhow just a couple more thoughts to chew on.

HTH

Bret P.

 

[Wolverine]

I have my DAC and my Oppo BDP 83 running through my preamp. The analog connections on the Oppo are used when I want to listen to SACD or other Hi Rez formats. I have the coaxial output of the Oppo running to my DAC. When I want to listen to the the DAC I select the Aux source on my preamp and when I want to listen to Hi Rez I switch my source on the preamp to CD and I am utilizing the analog output of the Oppo and bypassing the DAC. Easiest way to use the same transport for both Hi-Rez and Redbook play back.

 

[SterlingOne]

Interestingly enough, although we've now lived through about 40 years of DAC "upgrades" seems there's still no general acceptance of where the DAC should reside. Residing in a Preamplifier sounds good, but only until a new and improved DAC appears making the whole preamp obsolete. This makes me yearn for standardization of a DAC socket, which would allow upgrading without need to replace a whole component. On another note, I've got a lot of DAC redundancy for stereo media pleasure. Thing is, it's a multi-channel world we live in today so I've now routed my all of my source components to my OPPO's 8 channel DAC to be able to enjoy both stereo and multi-channel music.

I have my DAC and my Oppo BDP 83 running through my preamp. The analog connections on the Oppo are used when I want to listen to SACD or other Hi Rez formats. I have the coaxial output of the Oppo running to my DAC. When I want to listen to the the DAC I select the Aux source on my preamp and when I want to listen to Hi Rez I switch my source on the preamp to CD and I am utilizing the analog output of the Oppo and bypassing the DAC. Easiest way to use the same transport for both Hi-Rez and Redbook play back.

I've gotta tell ya, there seems to be 9 ways to Sunday to enjoy music when you have an OPPO. I've had my 205 for a couple of years and I'm still discovering ways to route stereo and multi-channel downloads.

 

[gvl]

Looking at the Stereophile review it is a good DAC for what it is but you're pretty much limited to 44.1 kHz sampling. You can get a USB to SPDIF adapter and find proper ways to downsample hires but you will be discarding whatever hires benefits there are. IMO invest couple hundred in a decent modern DAC instead that can take hires natively. SMSL SU8 or the like. Sell the Theta or keep it if it for secondary use if it has centimental value.

 

[Multiplex]

Thanks for the replies. Some pretty good ideas. I will probably invest in a new budget DAC for hi-res eventually. There are a crazy amount of options now. The various Toppings, SMSL-U8 (which looks a lot the same as the Topping, just with balanced outs,) and entry-level Schiits all look like great options.

I'm thinking I'll attempt using my current DAC, as well. I just want to try it. This might be what I will get to start with:
Signstek HiFi USB to Coaxial S/PDIF Converter Convert Digital to Analogue Signal Mini USB DAC PCM https://www.amazon.com/dp/B00FEDHHKE/ref=cm_sw_r_cp_apa_i_Qgy2Db530PW7X
It apparently converts USB to coax, and has a built in DAC. Anybody ever try one? I know it's cheap and cheesy. No way will it rate with the Theta. But it should hopefully be enough to tell me if streaming will work with the Theta, and whether it's worth persuing a better quality adaptor or not.

 

[gvl]

Skip the Singstek. You want a converter with asynchronous USB interface for your Theta. Spend a bit more on a Topping D10, that is probably the lowest cost decent entry, it has a reasonable DAC you can use for hires too.

 

[Multiplex]

Skip the Singstek. You want a converter with asynchronous USB interface for your Theta. Spend a bit more on a Topping D10, that is probably the lowest cost decent entry, it has a reasonable DAC you can use for hires too.

That is a great idea. I missed that the D10 has a coax output. It would make a decent little DAC that could be relegated to a second system when I upgrade my main, too.

The sample rate display is a fairly cool feature, as well.

 

[KarlK]

Theta DS-Pro Generation

Given my penchant for all things vintage I would hardly call that, let's say maturing, unit as "vintage", in fact several "Generation" variants of the Theta DS-Pro are still widely used and since these things last forever a 20+ year-old machine is just that, a young adult. Stereophile praised them enough so that their production facilities had to be relocated to a larger place. Have you ever had a look inside? That's where they put their money, while most others in the same class split between lesser parts inside in favor of fancier aesthetics.

 

[Multiplex]

Given my penchant for all things vintage I would hardly call that, let's say maturing, unit as "vintage", in fact several "Generation" variants of the Theta DS-Pro are still widely used and since these things last forever a 20+ year-old machine is just that, a young adult. Stereophile praised them enough so that their production facilities had to be relocated to a larger place. Have you ever had a look inside? That's where they put their money, while most others in the same class split between lesser parts inside in favor of fancier aesthetics.

You can definitely tell the quality by the weight of the thing. It feels like a high-powered amplifier, or something. I've never had this one apart. I may dabble in recapping the PS someday, but I'm a little too chicken to dabble with anything downstream from that.

 

[KarlK]

You can definitely tell the quality by the weight of the thing. It feels like a high-powered amplifier, or something. I've never had this one apart. I may dabble in recapping the PS someday, but I'm a little too chicken to dabble with anything downstream from that.

When it comes to electronics the it's often the heavier the unit the better. I know it's the power supply weighing in so to speak, and that's a good sign of other parts inside. Copper is expensive so it's not there just for show. That's what makes it hard no to laugh at a 12-lb receiver claiming 120wpc these days. These must be pretty thin watts but how thin is hard to tell since amperage is usually buried amidst tons of meaningless specs. I once inquired about it and the young salesman replied something that sounded kike "what's an amp hair sir?". "Ampere son, amperes and volts are the salt and pepper of good sound, if you like."