Twisted Pear Audio Opus DAC
Jun 20, 2011 at 11:30 AM Post #976 of 994


Quote:
Another thing, is it possible to run an opus module, metronome and spdif receiver from a single LCDPS?
 
Also how would IVY'(s) be wired for a dual mono setup? Would I even need two? I looked around and saw some people using 1 or 2 ivys for dual mono.



Yes, you can run OPUS, Metro and SPDIF receiver out of a single LCDPS. One side powers the digital section of OPUS, Metro and SPDIF board, the other side of LCDPS powers the analog section of OPUS
 
I would recommend that you get the basic set up running first (SPDIF receiver and OPUS) and then add the other components later to facilitate debugging in case you have problems
 
Jun 21, 2011 at 7:24 PM Post #977 of 994
I'm looking into building an OPUS as a summer project. Just a non-balanced one, I don't really plan on going balanced anytime soon, too expensive :frowning2:  I've built a MSSH and a bottlehead crack so far. 
 
Getting kind of confused as to what exactly I have to buy to build it lol. Do I just need the OPUS kit (unassembled), USB receiver module, and then a powersupply option? And of course a case.
 
Is there large difference between the placid powersupply kit and just the low current dual powersupply? 
 
Sep 12, 2011 at 2:17 PM Post #978 of 994
This is the most recent thread I could find on the opus dac, I've read a bit here and the diy forum, but I can't really be sure.  I'm currently using a laptop that would either have to be usb out or headjack to rca.  I'd like to be able to use optical or coax in the future.  Would this be a good pairing w/ an indeed G3?
 
Sep 15, 2011 at 1:36 AM Post #979 of 994
here's the reply I got from their forum
 
The Opus is basically just the DAC by itself and it has balanced output. If you want to get SE output you will need to either get the following:

Ballsie Lite Converter

Or Line stage with built in Ballsie

IVY

Even if you're going to go fully balanced, I would suggest you get the IVY board, it is much better for sound output.

You will need a power supply for the DAC. Depending on your budget, you can go these way. Upper is least expensive solution and lower is most expensive but better as well

1- Use LCDPS power supply to power analog and digital sections of the DAC independently or use one side of the LCDPS to power both analog/digital section of the DAC and the other side of the LCDPS to power the SPDIF tranceiver/MUX/USB

2- Use a Placid HD power supply to power both the analog/digital section of the DAC or use two of them to power them individually. Use LCDPS to power the SPDIF tranceiver/MUX/USB and use a Placid HD Bipolar Shunt power supply to power the IVY stage

3- Use any combination you like but the Placid HD Shunt power supplies are the best to power the DAC and IVY Stage. The tranceiver/mux/usb can all be powered by LCDPS.

If I was going to build this, I would use the following:
Opus DAC
Placid HD Shunt to power both Analog/Digital section of the DAC
IVY III Linestage
Placid HD Bipolar Shunt Power Supply for IVY III
Your choice of tranceiver/mux/USB
SPDIF tranceiver with I2S output
or
4:1 Mux receiver with I2S output (new version coming out soon...
or
USB receiver with I2S output (new version coming out soon...)

And of course transformers
Power transformers
You can use the 15V for DAC and IVY and Transceiver/MUX/USB. The 9V should also work well with the DAC and Tranceiver but not the IVY

Enjoy!
 
Sep 15, 2011 at 2:20 AM Post #980 of 994
he could also use a pair of line transformers for bal/se conversion, in fact the opus and all voltage out dacs pretty much, works very well with this setup. you do not need an IV stage, so i would suggest getting the ivy is overkill. a simple jfet or mosfet differential pair for a buffer would also do the job nicely
 
Oct 8, 2011 at 12:28 AM Post #981 of 994
Why does their SPDIF receiver have 4 I2S options while their current USB receiver only allow 24 bit I2S? Shouldn't the USB receiver just allow I2S and 16 bit or 24 bit depending on the source?
 
If you play a 16 bit music file from the source to the SPDIF receiver using 16 bit I2S it seems to sound better than 24 bit I2S I think although I also configured my Metronome and my Dual Mono Opus DAC in differential mode to 16 bit too.
 
Does anyone else have this setup and tried doing this?
 
In their manuals they keep asking you to set it up for 24 bit but it doesn't make sense if you don't usually play 24 bit files.
 
Oct 8, 2011 at 8:39 AM Post #982 of 994
standard pcm i2s does not come in 16bit flavor, only philips and perhaps sony format. all it does when feeding a 16bit signal to a 24 or 32bit dac with pcm input is pad the other bits with zeros. it doesnt resample unless you use metronome or similar afaik
 
Oct 8, 2011 at 3:59 PM Post #983 of 994
 
http://www.ti.com/lit/ds/symlink/pcm2707.pdf
 
Quote:
 
[size=x-small][size=x-small]The PCM2706 and PCM2707 can support the I[/size][/size][size=xx-small][size=xx-small]2[/size][/size][size=x-small][size=x-small]S interface, which is enabled by FSEL (pin 9). In the I[/size][/size][size=xx-small][size=xx-small]2[/size][/size][size=x-small][size=x-small]S interface[/size][/size]
[size=x-small][size=x-small]enabled mode, pins 4, 18, 19, 5, and 17 are assigned as DIN, SYSCK, BCK, LRCK, and DOUT, respectively.[/size][/size]
[size=x-small][size=x-small]They provide digital output/input data in the 16-bit I[/size][/size][size=xx-small][size=xx-small]2[/size][/size][size=x-small][size=x-small]S format, which also is accepted by the internal DAC.[/size][/size]

 
 
Oct 8, 2011 at 7:53 PM Post #984 of 994
I stand corrected, although thats not pcm, probably as long as its msb justified its ok
 
Oct 29, 2011 at 12:24 PM Post #985 of 994
TPA has a USB receiver that uses bus power and I'm looking for a USB receiver out there that uses an external power supply so I'm wondering if anyone else know a USB receiver like this or already using one in their TPA DAC configuration?
 
I'm looking for a non-TPA USB receiver that works in an TPA Opus DAC configuration that can run on TPA's LCDPS. Please let me know what's out there.
 
Nov 30, 2011 at 4:34 PM Post #986 of 994
Will the Opus and associated components be offered for sale again? Right now, every offering is 'out of stock'. It has the look of a dead product line, but there's no such annotation on the web site.
 
Dec 20, 2011 at 9:03 AM Post #987 of 994


Quote:
Will the Opus and associated components be offered for sale again? Right now, every offering is 'out of stock'. It has the look of a dead product line, but there's no such annotation on the web site.



"The Opus DAC is undergoing a redesign, and should be available again in early-2012."
 
Source: http://www.twistedpearaudio.com/digital/opus.aspx
 
Mar 23, 2013 at 2:27 PM Post #988 of 994
I just found this project while searching around for high-end DACs. They released V2.0 which was updated to WM8741.
 
An unassembled kit is only 55$, which makes it a nice project even for starters. But I'm wondering just where this thing fits in all the current offering. How does it compare to other DIY projects like the Gamma II and PupDAC?
 
What's really interesting about this project is you can get two boards and have a truly balanced DAC at a reasonable price. But would this be considered an Hi End DAC by today's standards? 
 
edit: Never mind, just realized a single board already is balanced. So what's the point of dual boards? A theoretical gain of 3 dB in SNR?
 
Mar 23, 2013 at 6:23 PM Post #989 of 994
Quote:
I just found this project while searching around for high-end DACs. They released V2.0 which was updated to WM8741.
 
An unassembled kit is only 55$, which makes it a nice project even for starters. But I'm wondering just where this thing fits in all the current offering. How does it compare to other DIY projects like the Gamma II and PupDAC?
 
What's really interesting about this project is you can get two boards and have a truly balanced DAC at a reasonable price. But would this be considered an Hi End DAC by today's standards? 
 
edit: Never mind, just realized a single board already is balanced. So what's the point of dual boards? A theoretical gain of 3 dB in SNR?

The last time I looked (it's been awhile), $55 was far from the actual total.  The Opus as it stands needs the power supply and the input boards (SPDIF/USB).  It starts adding up quickly.  I could swear in its original implementation, it needed I2S output boards, too, but maybe that's the difference with the new chip and the overhauled design.
 
All that said, it was probably the best in the world at the time, until they came out with the Buffalo.  Just giving you info from what I've read from people I trust, but the Buffalo may represent true top-of-the-line capability on par with any DAC.
 
Mar 23, 2013 at 9:57 PM Post #990 of 994
Thanks tomb. I realized it needs a PSU, an SPDIF to I²S converter and maybe even an output buffer. But even the Buffalo and the AckoDAC need these things, so the DAC itself is still 1/6 the price of those. 
 
Though it's not a very good comparison because you can't have the Buffalo as a kit, only as a fully assembled board. I mean, soldering the board up is the best part of the whole DIY hobby, so why not offer a kit? 
frown.gif

 
But yeah, when I look at all the other modules needed, it goes get expensive really fast.
 

Users who are viewing this thread

Back
Top