Again, the dac we are talking about works much like Benchmark DAC-3:
Benchmark DAC3 HGC - Digital to Analog Audio Converter - Benchmark Media Systems
Benchmark DAC3 HGC D/A preamplifier-headphone amplifier | Stereophile.com
According to Stereophile when they reviewed DAC-3, it was SOA and A+ recommended. The approach can be audiophile quality, if done correctly.
Again, this is like DAC-3. It can work fine if done correctly.
There is some jitter from PLLs in LMK01000 and in AK4137. However, as you say, if the AK4137 I2S output signals are setup according to the dac chip I2S input specifications then everything should work correctly. Yet, some further improvement might be obtained by reclocking after AK4137. That's something I considered doing, but never got around to trying.
I tried it and empirically found that sound quality can be very similar to Benchmark DAC-3. Maybe even a little better than DAC-3 in some ways, according to Jam (a professional high end audio designer who listened to both my dac and DAC-3 in an A/B comparison).
Regards,
Mark
Hi Mark.
That's wonderful. I will see what it can be achieved. Good luck to the project.
I have a AK4137 board, maybe I should give it a try. I'll post the update if I have down the road. Does it convert everything into DSD?
But for now, I need to try Greg's Rasmussen filtering solution to see how much improved he got.
Regards,
Ian
The 4137 is a very good part if you are looking for an easy to implement solution to get to the big numbers everyone is talking about - DSD512 and so but in the end for me and a lot of friends it is just midfi. 
Spectacular at first but then you realize everything sounds in the same processed manner, don't take my word for it, listen.
Spectacular at first but then you realize everything sounds in the same processed manner, don't take my word for it, listen.... DSD512 and so but in the end for me and a lot of friends it is just midfi.
AK4137 cannot do DSD512, the maximum is DSD256.
It will sound as you say if implemented incorrectly. I found it difficult to get AK4137 to sound its best, and so far as I know nobody else has ever successfully done it that particular way. As I said, my experiments showed that clock timing for best sound quality was critical down to 150ps or so, which I determined by checking sound quality at each LMK01000 150ps delay step. Of course, that was with the clocking set up as I have already described, the only experiment I can attest to.
Also, I would say that all dacs have filters that sound a particular way. Output stages and other design choices have their sound too. It's just that some people don't notice the way in which everything sounds the same when played through a particular dac design.
Last edited:
Burn-in for a couple of days, I like the sound of OPA1612 OPAs more than before. I use the balanced output, so the OPA for SE output was uninstalled.
BTW, all OPA1622 adapters were shipped as letters to whom that messaged me the shipping addresses.
They will be received soon. Please let us know for update
OPA1612adapter by Ian, on Flickr
Regards,
Ian
BTW, all OPA1622 adapters were shipped as letters to whom that messaged me the shipping addresses.
They will be received soon. Please let us know for update
OPA1612adapter by Ian, on Flickr
Regards,
Ian
Correct, it was a long time ago
You are probably right, implementation is most important.
This message got lost in the square wave discussion.
What are your thoughts/experiences?
Correct, it was a long time ago
You are probably right, implementation is most important.
I see more new material being released on cassette than DSD. I keep hearing that DSD is the new dawn, I remain to be convinced.
With Ians DAC now implemented with passive Lundahl LL1544A transformer output stage, red book has never sounded so good.
I have a £ 10K vinyl source to compare.
You can do it but the problem it that one group can change the other group at very high current if one group is empty and the other is full.
Ian
Transformer I/V sounds more nature and analog than I/V std. But I/V std has better high and low range
. So it would be totally up to your personal preference. Ian
Got the ll1674 working. Set up with 221r resistors.
An interesting listen, much the same difference as I've heard going from an active pre to an MFA transformer pre. Smoother, more relaxed but a little dynamically restrained. I cant hear any difference in the treble, I'm good to 16.5k so maybe any roll off is above my hearing range. The bass is maybe a tiny bit more damped, pillow in kick drum kind of thing.
Overall quite a subtle change, I could comfortably live with either. The question is do I strip back the unused 13v rails to give 2 additional rails for the dac board?
An interesting listen, much the same difference as I've heard going from an active pre to an MFA transformer pre. Smoother, more relaxed but a little dynamically restrained. I cant hear any difference in the treble, I'm good to 16.5k so maybe any roll off is above my hearing range. The bass is maybe a tiny bit more damped, pillow in kick drum kind of thing.
Overall quite a subtle change, I could comfortably live with either. The question is do I strip back the unused 13v rails to give 2 additional rails for the dac board?
Well...
I tried it and there is certainly more dynamics, the difference is quite clear. I have put two battery boards in parallel for testing, by turning one off and on, the difference is audible.
To let the batteries charge up to the same amount (preventing current flow between batteries) I now have connected the two rails of one board in parallel, one board is powering the + line and one the - line. Charging and using at exactly the same charge current/load. Seems to work good.
So even halving 6mohm does make a difference.
If there is one thing I have learned in audio it is that the power supply is almost always the weakest link.
Powering avcc with its own battery makes for a smoother sound, less edgy indeed.
Is it also beneficial to separately power dvcc and vcca?