John Curl's Blowtorch preamplifier part III

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Alrighty then.....

If you are thinking about buying a dac or a dac board, I would suggest that offerings will probably get better if you can wait another couple of months. Allo has announced an ES9038Q2M USB dac that can do DSD512 in synchronous/master mode, and with measured distortion of -123.7dB@1kHz (using an AP). It has an 8-layer board, and they apply Ott very carefully. It should be pretty good, I would expect.
 
Then you should check out Arthur HIGH-END AUDIO and Arthur Salvatore .
I think his points about THD not THD+N should be measured as the output goes to 0 (so does Earl Geddes BTW) are very interesting. Everyone worries about cleanly driving their speakers out of their surrounds.

10-4....thanks,I’ll check that out.

I factor in x max and don’t like to be over 75% at my max listening level which calculates to about 50% @ 90-95db...my setup is designed from the ground up.

Of course these are calculated from box sims and xo’s so some error is expected but it keeps things leashed in a little with room for dynamics.
 
If you are thinking about buying a dac or a dac board, I would suggest that offerings will probably get better if you can wait another couple of months. Allo has announced an ES9038Q2M USB dac that can do DSD512 in synchronous/master mode, and with measured distortion of -123.7dB@1kHz (using an AP). It has an 8-layer board, and they apply Ott very carefully. It should be pretty good, I would expect.

Ill google it but I’m really liking this RME......it ticks a lot of boxes.

What’s the $$ looking like on the Allo?
 
A thin sheet of aluminum will do **** to screen magnetic fields. Make it 12mm thick and 200mm high on both sides of the board and we can talk about.

And please stop this mimosa pudica attitude. Expecting praises only is the worst way to learn something useful. If you don't want critical feedback, then stop posting about your stuff.

Some screening yes, but still there is direct output.
If you are so against output inductor on the PCB board, do you have measurement to show how much THD will increase with output inductor on the board comparing with output inductor far from the PCB board?
I know that D. Self showed inductive influence between channel depends of angles between coils.
There so many amps with the output inductor on the board, they must all sound terrible.

By the way I don't have any commercial interest in that amp.
 
Ill google it but I’m really liking this RME......it ticks a lot of boxes.

What’s the $$ looking like on the Allo?

The RME ADI-2 PRO is about $2,000.
The Allo USB dac is expected to be under $200.

The non-PRO version of ADI-2 is another story if that's what you are thinking of. I personally would not buy one for hi-fi, but I would use one for measurement applications. Also, they are SPDIF only, unlike the PRO version which includes USB.

Haven't tried the dac-only version myself.
 
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Alrighty then.....

RME ADI-2 dac?


AKM 4490 based.....nice build quality from the looks and reports.

It has many dsp options including eq

My questions would be....

1) RME....reputation in pro stuff is good afaik ? This is stepping a toe into home audio waters based on a pro unit.....could be beneficial?

2) does the addition of dsp at this point help or hinder sq....I’m thinking maybe it’s a nice option for overall system tuning?

3) reports are awesome comparing it to or better than chord,benchmark,Mytek...
Any experience/familiarity with RME here?

This is a big investment for me and I’d like to get the best bang for buck possible.....if it’s beating $2500 dacs at $1,000 I’d say that’s good value?

No affiliation,just found it web cruising

Thanks, bob

Bob,

I have one since about 2 years and it is great, what can i say? For use as a measurement input device, it is not far behind pro gear like AP. For music reproduction, it is flawless. I something happened with the one I have, I would order a new one tomorrow.
 
Then you should check out Arthur HIGH-END AUDIO and Arthur Salvatore .
I think his points about THD not THD+N should be measured as the output goes to 0 (so does Earl Geddes BTW) are very interesting. Everyone worries about cleanly driving their speakers out of their surrounds.

You have made this point before and I am totally in agreement that this is relevant since we can perceive signals way below the noise floor. It is most pertinent to have THD figures without the noise component. Why is it, that manufacturers don't provide this information? All spec sheets of amplifiers I am aware of show the same noise dominated down slope of THD+N. I would like to see what goes on within that triangle. Hearing is logarithmic, correlated perturbances matter, even if they appear to be swamped by noise.
 
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