Russ White said:
Very cool! 😀 I see on the spec sheet that the rear control circuit board is in fact too large for a 1U box (1.7"; box is 1.5" max). However, all is not lost because they also make a smaller 2 X 20 version that should fit and it uses the same control interface. The characters would be noticably smaller - and I agree that the larger text in the model you selected would be generally preferable...
I *really* appreciate this nice work! 😉
Frank in Mpls.
hey guys!
I recently replaced one of your older CS boards with the newer Wolfson receiver board for a friend. There are two Opus boards in dual mono configuration with a Zapfilter on the output. Things were working fine before. After the receiver transplant, my friend is getting soft intermittent clicks that are not in any particular pattern with the music. Like I said, things were working fine before. The 7.5VDC supply is clean and the input is via a piece of shielded coax. The switches are set as follows:
AIF/MS 1
TXSRC 0
AIFCONF1 0
AIFCONF0 1
(where 1 is far "LEFT" if you're reading the silk and 0 is far "RIGHT")
Assuming the above is correct and the wiring is correct, all I can think is that the I2S lines might have gotten crossed when the unit was shipped? I think this is unlikely, but could explain the symptoms. Yet, every time this has been a problem, the noise has been much more obvious, so that makes me think it might be either configuration issue or a bad board?
What would you guys recommend?
edit: I read some posts, I guess it's probably the i2s wiring afterall.
I recently replaced one of your older CS boards with the newer Wolfson receiver board for a friend. There are two Opus boards in dual mono configuration with a Zapfilter on the output. Things were working fine before. After the receiver transplant, my friend is getting soft intermittent clicks that are not in any particular pattern with the music. Like I said, things were working fine before. The 7.5VDC supply is clean and the input is via a piece of shielded coax. The switches are set as follows:
AIF/MS 1
TXSRC 0
AIFCONF1 0
AIFCONF0 1
(where 1 is far "LEFT" if you're reading the silk and 0 is far "RIGHT")
Assuming the above is correct and the wiring is correct, all I can think is that the I2S lines might have gotten crossed when the unit was shipped? I think this is unlikely, but could explain the symptoms. Yet, every time this has been a problem, the noise has been much more obvious, so that makes me think it might be either configuration issue or a bad board?
What would you guys recommend?
edit: I read some posts, I guess it's probably the i2s wiring afterall.
I have a simple question, please forgive my ignorance.
Russ, why are you using an IVY with the OPUS? I understood that the OPUS was V-Out, and then use a BAL/SE only... Have I missed something here?
Also, how difficult would it be to "upgrade" my 8740 modules with the new I.C.?
Thanks
Simon T
Russ, why are you using an IVY with the OPUS? I understood that the OPUS was V-Out, and then use a BAL/SE only... Have I missed something here?
Also, how difficult would it be to "upgrade" my 8740 modules with the new I.C.?
Thanks
Simon T
Pulse-R said:
Hi Simon,
The IVY is just as suited to voltage output DACs as Current. 🙂 The reason I like to use it is because of the super symmetrical nature of the THS41xx it cancels some distortion and common mode noise which could come from the DAC. This results in very good THD and DNR.
Using the IVY with the opus is a natural choice so long as you keep the input impedance of the IVY >= 1K.
In fact here is a cool trick I am going to do today.
1) Setup two Opus in mono mode. When you do this one channel will be the same audio channel as the other but inverse phase.
2) Setup an IVY for each opus wiring each channel to an input on the IVY. You will get a mono balanced signal out of what is usually a stereo SE signal from the IVY. 🙂 The balanced outputs of the IVYs are unused in this case. This should result in even better DNR. 😀 This is very similar to the way they do Dual mono in the data sheet, but should be even better! 🙂
Cheers!
Russ
IVY in dual mono mode.
Holy Spumoni! Its very very nice. 🙂
Only listening for about an hour, but so far its great!
Cheers!
Russ
Holy Spumoni! Its very very nice. 🙂
Only listening for about an hour, but so far its great!
Cheers!
Russ
I forgot to mention one of the key benefits of the IVY.
No output capacitors on the DAC. 🙂 Everything is DC coupled. Bass is pure and clean and phase accurate. Gotta love it.
Because OCM of the THS4131 is at GND there is no offset to GND at the balanced outputs or the SE outputs.
Cheers!
Russ
No output capacitors on the DAC. 🙂 Everything is DC coupled. Bass is pure and clean and phase accurate. Gotta love it.
Because OCM of the THS4131 is at GND there is no offset to GND at the balanced outputs or the SE outputs.
Cheers!
Russ
Hi Russ,
This sounds like my kind of mod 🙂
Does it allow you to do away with the load-balancing resistors, too ?
Colin
This sounds like my kind of mod 🙂
Does it allow you to do away with the load-balancing resistors, too ?
Colin
akione said:
Yes, because each channel is handled separately. 🙂
I think this has been my favorite experiment so far.
Cheers!
Russ
Okay, somebody has to ask ...
It is very obvious that you like the dual mono WM8741 DAC. But do you like it better than Buffalo?
It is very obvious that you like the dual mono WM8741 DAC. But do you like it better than Buffalo?
Ahh yes, I see what's going on. Each channel has its own line driver, effectively doing the load-balancing, with the summing done in the LME49720.
I expect that sounds very tight and dynamic. 🙂
I assume you've set everything for unity gain. 1k's on the THS's and 2k's on the LME's ?
Question is - Can I fit 2 more IVY's in the case ? 😀
Colin
I expect that sounds very tight and dynamic. 🙂
I assume you've set everything for unity gain. 1k's on the THS's and 2k's on the LME's ?
Question is - Can I fit 2 more IVY's in the case ? 😀
Colin
Russ,
The new DAC looks great. Would you consider doing something with the new Asahi DAC- AKM4397? Sorry if this has been asked before or is considered intruding on this thread. Just curious!
The new DAC looks great. Would you consider doing something with the new Asahi DAC- AKM4397? Sorry if this has been asked before or is considered intruding on this thread. Just curious!
khundude said:
When you get around to it, Russ... 😉
It will be interesting to learn:
a) which mode is better: 'DSD direct' or 'DSD plus' (or, whether balanced outputs via a THS4131 are sufficient to remove high frequency noise in the 'DSD direct' mode)?
b) whether mono mode (compared to stereo operation) significantly improves the DSD output signal. With all of the available configuration and filter options, it seems that software control flexibility becomes ever more desirable.
Still, you gotta know by now that lots of people trust your ears!
Frank/Mpls.
jpak said:
There is so much on my plate right right now it hard to say I would ever be able to get to it. But then I would not rule it out either. 😉
francolargo said:
When you get around to it, Russ... 😉
It will be interesting to learn:
a) which mode is better: 'DSD direct' or 'DSD plus' (or, whether balanced outputs via a THS4131 are sufficient to remove high frequency noise in the 'DSD direct' mode)?
b) whether mono mode (compared to stereo operation) significantly improves the DSD output signal. With all of the available configuration and filter options, it seems that software control flexibility becomes ever more desirable.
Still, you gotta know by now that lots of people trust your ears!
Frank/Mpls.
Thanks Frank, 🙂
I am in the midst (meaning parts strewn about) of modding my SACD player for proper (SDIF2) DSD output. Once I have that done I will test the Opus with DSD.
For tonight I am content to drink my freshly kegged "celebration ale 2008" which I made for a fourth of July party we are throwing. It's a classic British brown ale with just a hint of chocolate malt and roasted barley. Hops are East Kent Goldings and Fuggles to finish.
I used the same yeast they use at New Belgium Brewing to make "Fat Tire". I think its the best batch this year. 😀Back to DSD. 🙂 When I can I will test it every which way I can think of. 😀
Cheers!
Russ
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Russ White said:
For tonight I am content to drink my freshly kegged "celebration ale 2008" which I made for a fourth of July party we are throwing. It's a classic British brown ale with just a hint of chocolate malt and roasted barley. Hops are East Kent Goldings and Fuggles to finish.
!!OT alert!!
That looks so good...makes me want to drive up from Atlanta just to get a sip! 😀 I'm more of a fan of the New Belgium Trippel than Fat Tire, though.
BrianDonegan said:
Do you guys have a preliminary layout of the board you'd be willing to show?
Thanks Russ, looks nice! I'm guessing the i2s output is arranged in that order (MCK, G, BCK, LRCK, DOUT) due to pcb layout issues. Is this in your next batch of modules?