Partially as I have an initial DAC prototype working. But that doesn't mean you need a new DAC to appreciate Quartet - recently I have been showing the pre-production Quartet to a few selected audiophiles via a Dave against an M scaled Dave, and the subjective results were very much better than...

Any digital circuit can introduce RF noise. The issue here is how much, and this depends upon power - Toslink optical receivers have the lowest power consumption. By far the worst is USB, as this requires a processor to buffer and decode, and that creates two orders of magnitudes more random RF...

I covered this aspect in recent NYC and Singapore CanJam seminars - here are the relevant slides: I think optical has a bad reputation because it sounds rich, warm and naturally rounded due to the reduction in noise floor modulation. This is a less impressive sound than the etched and forced...

Clearly the writer doesn't have a clue how sampling theory works - the diatribe is just mumbo-jumbo. To say that with more taps "they will end up blending to each other, keeping the "build-up" in between at higher level. Closer these are to each other, higher the build-up. In other words, these...

I would hesitate to put a number on the sound quality from the DAC as the analogue and PSU is indeed vital. But if pushed for a number, it would be very much more than 90% is dependent upon the interpolation filter and DAC implementation. The problem is so many listeners are not good at...

It doesn't need 24 hours - that applies to Hugo 2. How long it needs depends upon the initial charge state, and the fact that the last charge (from 95% to 100%) is a tiny trickle charge and this can take a couple of hours alone. And because it's a trickle charge, it's uncertain when it will...

The new Quartet M scaler will have more complex and lossless EQ built in. Oddly enough, I am putting the finishing touches to it right now. Having EQ that does not mess up sound quality or musicality is a really useful tool.

Quartet's single BNC and optical OP is different to the Hugo M scaler - I decided to fix the OP at 176.4/192k as it then allowed for an optimised data path. All inputs are converted to 705.6/768 kHz, then the 176.4/192 is created by decimation from the common 705.6/768 kHz - but it's by no means...

Yes Quartet M scaler will have 176.4/192 kHz toslink OP, plus 176.4/192 kHz coax and of course dual BNC at 705.6/768 kHz. On another note, I will be posting my new seminar slides here after Singapore CanJam.

I really welcome suggestions for EQ - but as @hypos said, you can't please everyone. The settings for the shelf and peak were determined so that one could compensate for a first order response for bass - a lot of Japanese IEMs have a first order roll-off at 125Hz, and with the appropriate bass...

Thank-you for your kind comments. Ah you spotted that! I occasionally add intentional little hints to my posts. Yes the base PSU design has some variants that will suit other future products - in particular the Ultima DAC.

So long as it's not white it can't clip under any circumstances even with the max digital input of 0dBFS.

No - the PSUs need to be independent to prevent RF current flows. The new PSU works by having an extremely high impedance at RF - in particular the 1MHz to 10GHz band. This high impedance means that RF currents can't flow. By combining PSUs together provides a lower impedance path to couple...

Optical with my DACs is the reference sounding source in that jitter doesn't matter, and there is zero possibility of RF noise currents flowing into Mojo 2's ground plane. I did use optical when listening to Mojo 2 when developing it. USB on desktop can sound identical to optical with an...

Except the real surprises will be what's inside them... well over 5 man years of development (and counting) has gone just into these two new products. Correct - I have had no involvement in Suzi. The PSUs are my own design, and the most advanced PSUs available with new tech to isolate RF...