[pabbi1]

You can definitely stack them - and IIRC, there is some benefit in reducing stray voltage in doing it that way. I had a config like that, and it was just fine.

 

[dgbiker1]

Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif You can definitely stack them - and IIRC, there is some benefit in reducing stray voltage in doing it that way. I had a config like that, and it was just fine.

Excellent! Thanks for confirming that Pabbi.
Do you recognize the Nabu? I think that was your find if I remember correctly. Nice find on that one, thanks

I'm ordering two more for my eventual beta22/sigma11 build.

 

[fordgtlover]

Does anyone have listening impression and comparisons to commercial DACs?

Heaps of people seem to have gone down the TP path, but I can't find too many reviews.

 

[BrianDonegan]

Quote:

I just spent the day laying out my build and I'm in a bit of a pickle with the power section.

You could also stack both PSUs and place their inputs right next to the trafos.

 

[dgbiker1]

Quote:

Originally Posted by BrianDonegan /img/forum/go_quote.gif You could also stack both PSUs and place their inputs right next to the trafos.

Thanks for the suggestion Brian, that was my first inclination, I just thought it would affect the performance of the heatsinks. But if you say it's kosher I'll definitely stack the PSUs as well, I still need room for a third PSU for my logic boards. For peace of mind I might just stick a thermistor on the bottom board so that I can flash an alert on the LCD if things get too toasty.

 

[BrianDonegan]

Quote:

Thanks for the suggestion Brian, that was my first inclination, I just thought it would affect the performance of the heatsinks.

If this is a concern, put the bipolar supply on the bottom. It has less voltage drop so it's heatsinks should be a little cooler.

 

[dgbiker1]

Thanks for all the help and the fantastic work Brian and Russ, another Opus lives! Everything fired up on the first shot to my amazement. It's a pretty successful build in my book when my biggest problems are the lack of an RCA-RCA interconnect and that I need to order some insulated RCA jacks

Sounds great! I'll post a couple pictures when the faceplates come in and I have the interface programmed.

 

[Russ White]

dgbiker1,

Excellent work!

Please let me know what you think of that combo.

Cheers!
Russ

 

[Ech0]

@ dgbiker1

Very neat work & a good shot of the wiring. Well done!

Is the shielding recommended / required in this build? I hadn't planned on doing this, but, certainly can change if need be.

 

[Russ White]

Quote:

Originally Posted by Ech0 /img/forum/go_quote.gif @ dgbiker1 Is the shielding recommended / required in this build? I hadn't planned on doing this, but, certainly can change if need be.

If you are neat with your wiring, no its not strictly required, but it certainly will not hurt, and in fact will make a more bullet proof DAC to be certain.

Cheers!
Russ

 

[dgbiker1]

Quote:

Originally Posted by Russ White /img/forum/go_quote.gif dgbiker1, Excellent work! Please let me know what you think of that combo. Cheers! Russ

Thanks Russ

I'll post my impressions soon, right now I'm just waiting on some wire from navships to replace the cheap wire I used for now. It's already amazing though, I was listening to one of my best test tracks (probably top 3) that I had always thought was recorded as a live studio session. For the first time with ANY equipment, I picked up that one of the instruments is actually recorded loop from the barely audible shuffle of one of the musicians. More important than "technical" feats like that, everything sounds much more realistic and grabs your attention. I would describe it as fun/engaging without loosing out on the realism. It's also dead quiet, my amp can't even go loud enough to hear any hiss coming from the DAC.
In a nutshell: I won't have source upgradeitis for a LONG time

The only thing I plan on adding down the road are a metronome (as soon as they're available), and later a ballsie so that I can switch between IVY and ballsie.

Quote:

Originally Posted by Ech0 /img/forum/go_quote.gif @ dgbiker1 Very neat work & a good shot of the wiring. Well done! Is the shielding recommended / required in this build? I hadn't planned on doing this, but, certainly can change if need be.

Are you talking about the silver colored plate? It shields... but only as a secondary benefit. The real reason for putting it there was aesthetics

"Phase 2" of this project is building the top of the case to open up (I was torn between a clean looking closed top and a nerd eye-candy clear top... so I'm doing both). I have a microcontroller that will operate a servo to open up a 7" square in the top over the boards, all you'll see are the three boards over the silver plate with aluminum mesh around the sides, a red glow under each board, and white spotlights lighting each board. I just wanted the silver plate to cover up some of the wiring and the hideous oxidized gold look of the case interior. It also leaves room to route LEDs under the boards for background lighting.

The shielded power section was already there with the case so I made use of it, but putting a few inches between the PS section and the boards would have probably been fine.

 

[Ech0]

Thanks for the info guys.

I was talking about the shield that apparently came w/the case that one of the power supplies is hooked up to.

Quote:

Originally Posted by dgbiker1 I have a microcontroller that will operate a servo to open up a 7" square in the top over the boards, all you'll see are the three boards over the silver plate with aluminum mesh around the sides, a red glow under each board, and white spotlights lighting each board.

 

[dgbiker1]

Finally got my FPE panels and navships wire today, had everything cased up and running by 11:30 PM. It was fun explaining to the grocery store clerk why I needed 3 tubes of superglue at 11:00 PM

Overall, I'm extremely happy with the Opus/IVY configuration. It's added warmth to my setup without losing any detail (added more detail in fact). Matched with the MkIII and K701, it's exactly the sound I've been looking for. FWIW the navships wire sounds no different from the 18ga solid core tinned copper wire from Fry's that I initially put in. I'm not complaining though

(yes, that's a blackberry trackball)

Home screen says "Opus" / "Twisted Pear"

Some of the navigation menu:

I have the servo and gearbox for the convertible top ready... but I need to take a little break from this project

 

[Reynaldo]

First of all, before you all start picking on me, a parmetal enclosure is on its way, the dac won't stay in the packing box forever, now that on the side, I would like to share my experience so far with the Opus. The idea of a Dac came more from necessity than desire, this year I moved from Puerto Rico to Texas, from a house with a dedicated listening room to a two bedroom, two bath. I new I could not have the space for a home theater rig and my 2 channel audio set up with turntable, phonostage, and all, I had to simplify somehow, so with a broken heart I decided to sell my Rega Jupiter Cd player, a very musical cd player, with a very analog like sound. So I start looking for a universal player, and then I started reading all this great reviews about the oppo 980 dvd player, and how good they sounded, even stereophile took the time to review the thing and it did pretty good, so I went ahead and ordered one, of course I wasn't expecting the oppo to equal the performance of the rega, but you know, I thought I could live with it, well I could not. Don get me wrong, the oppo does a hell of a lot for the $170 you pay for it, but definitely it is not a giant killer. They never are. So I had to do something, I had been reading about the Opus for quite a while and intrigued me a lot, no many DIY offers around and Ebay flooded with dacs using old chips, so I took the plunge and ordered the basic configuration for the Opus, oh baby what a pleasant surprise this little device has been, music is alive with good sense of space and timing again, yes I could use a little more gain, so I guess the Ballsie is in order, but the rest of the options are just as exciting, usb, balanced connections, etc, I really don't believe in burn in for digital devices, my opus has played for 10 hr only and it makes the oppo sound 100% better, If with time things will get better, well welcome, but right now I can sit again and listen to cd's again. For those in doubt, go ahead, I am not digital expert, but I know good sound.Thanks to twisted pear audio crew. Great little device.

System:

Oppo 980
Rega planar 3 w/DL103
Hagerman Bugle phono
Jolida Hybrid 1501 RC amp
GR Research AV1 speakers
canares speaker cables
canares interconnects

 

[akione]

Hi Reynaldo,

The basic Opus is very good, but, as you say, it benefits greatly from the addition of an output stage.
Either the Ballsie or IVY (or both

) is great. I would also recommend that you add the Metronome, too,
it does make a difference. You can, of course, do it bit-by-bit.

Anyway, I'm pleased you like the Opus. It's been a bit overshadowed recently by the Boffalo, but I'm very pleased with mine.

What's wrong with the existing case ???