first of all I like to thank John for another great review.
Not only because of the results but how he sets it up, describes, draws conclusions !!
There had been a number of questions appearing which I would like to answer here.
... about the releasing of some other balanced (headphone) amps ...
Well, we´re late with developing. This is because most times the relevant people in charge of this job
are permanently engaged in the test bay for our series products due to high sales.
Also we had been in charge to develope 6 new headphone amps for Lake People which will
replace the current models from next year.
So we hope that we can release at least the balanced amp known as V281 next spring.
By the way, we have two pieces of Prism Sound´s "D-Scope" for measuring purposes,
accompanied by a Rohde + Schwarz "UPL" and 5 oscilloscops, all Tektronics, from "TDS 340" downwards.
@ Tom W
... about the use of Dip-switches compared to jumpers.
First of all, the way how we adapt the analog output level has to be made close to the depending circuitry as the traces are very sensitive to pick-up noise.
And we would not have this extraordinary THD figure when we would do it in another way.
We have chosen Dip-switches instead of Jumpers because we felt that these are more easy to operate for the average user.
In 25 years of experiences with electronic circuitry we have never faced a broken or not working Dip-Switch. Dip switches are the more expensive solution.
Of coarse the contacts from our Dip-switches as well as our Jumpers employ gold plated surfaces.
... about the internal unity gain level from a DAC ...
A current output DAC does not have a specific output level as this is made during the I-U (current to voltage) conversion in the first analog stage after the converter.
But assuming there would be a direct voltage output this would mirror a level of approx. +8 dBu / about 2 V.
When this level is present at a balanced output another 6 dB gain is achieved, so +14 dBu would be a "native" balanced output level from a DAC.
Feel free to ask more questions,