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Using the ISO Regen with Phasure LUSH USB Cable

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Superdad   

Cool topic gents! (And @elcorso, it's good to see you about here more again.)

 

I'm typing on my phone so I'll be brief with a couple of comments:

a) the idea--and execution--of our USPCB A>B Adapter is to perfectly relay whatever USB waveforms it is given, passing them through without altering signal integrity at all.  Think of it simply as a circuit board extension of, typically, the output of the ISO REGEN.  That is really what it is.  4-layer PCB, microstrip trace impedance control, layers used for ground/shielding, even the pins of our male 'B' plug PCB-mount innovation taken into account.

 

b) If people enjoy/prefer a USB cable after the ISO REGEN, that is perfectly fine.  It just means they are preferring whatever alteration/effect that cable has on signal integrity and impedance match.  

 

c) Idealized SI (see our published eye-patterns) is just one of the goals of the ISO REGEN. The SQ contribution of the Crystek 575 is easily heard (and was compared during development) yet I doubt the eye-pattern would spotlight that.

 

d) It is possible that preserving perfect SI is not necessarily the very best thing for SQ.  Maybe starting with great signal integrity and isolation coming out of the ISO REGEN and then altering it in a deliberate way (something Peter--perhaps unlike other USB cable makers--may be doing intentionally) can result in something desirable.

 

e) It is important to keep in mind that the purpose and mechanism by which USB cables and hub-based regenerators work is in altering what goes on inside the DAC's USB input stage--specifically the PHY and processor.  Ground-plane noise and bounce, packet-data noise, excess spurious voltages generated (all ways of saying mostly

the same thing) can and do occur in the DAC's USB input.  And even digital isolators (so called "galvanic isolation") on the I2S output lines after the USB processor will pass along stuff that gets "baked into" the signal (John wrote a full technical explanation of how that happens).

Ultimately we hear this because of its effect on the DAC's master clock at the DAC chip's clock input pin.  That is measurable.  

 

My sample of @PeterSt's Lush cable gets delivered today, but I am on the other side of the country visiting my father with my teenage sons for the weekend. I'll try to take a listen next week.

One thing I wonder is if folks enjoy the effect of the Lush after the ISO REGEN, would a shorty version, (ala what a few other firms started producing in the wake of the original USB REGEN's massive success in 2015-16) sound better?  Or is there some aspect to the inductance/capacitance/impedance characteristic of the Lush that its effect is enhanced by the length?

I am open-minded as always.  

 

--Alex C.

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rickca   
20 minutes ago, Superdad said:

One thing I wonder is if folks enjoy the effect of the Lush after the ISO REGEN, would a shorty version, (ala what a few other firms started producing in the wake of the original USB REGEN's massive success in 2015-16) sound better?  Or is there some aspect to the inductance/capacitance/impedance characteristic of the Lush that its effect is enhanced by the length?

Alex, following is from Peter's Phasure forum post:

70cm is the shortest length which is mainly because of the somewhat odd bending capabilities of the cable;
At the "A" side of the cable (this is the PC side) the cable is made so that it can bend up and down - not sideways. At the "B" side (DAC side) it only bends side ways.
Both combined implies that you need a bit of length to go from the one device to the other.

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I just posted my impressions of Lush over here:

Right now the sequence of USB connectors in my baroque USB chain is: Curious - USPCB - Lush > DAC.

 

I hit an equipment snafu - @Superdad - check your email - but I will eventually try other sequences.

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rickca   
1 minute ago, Superdad said:

From this now I think I might know what the Lush is about

You may be the only one besides Peter!  There has been a furious wave of speculation and probably most of it is off the mark.

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k-man   
3 hours ago, Superdad said:

From this now I think I might know what the Lush is about and we may once again have a case of working privately with similar techniques on opposite sides of the world.

Project Shush :P

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Em2016   
6 hours ago, Superdad said:

we may once again have a case of working privately with similar techniques on opposite sides of the world. This could impact a product we have had in the works for a while. 

 

Wowza. My ears popped up at multiple things here :o

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BigAlMc   
On 04/08/2017 at 2:26 AM, lmitche said:

I am finally satisfied with the quality of the music produced by my system.

Wow! Quite a statement. I've read quite a few of your posts so this is saying something. 

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Superdad   
46 minutes ago, Guidof said:

@Superdad Have you had a chance to try your LUSH cable? Any impressions? Positioning?

Best regards,

Guido F.

 

Hi Guido:

No I have been too busy with production tasks--and with tilting at windmills over various mis-measurements and attacks...  :P

Hoping to give a listen to it this weekend.

Best,

--Alex

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Superdad   
2 hours ago, johndoe21ro said:

Alex, what about that LUSH cable? :D

 

It is interesting.  Still getting used to it.  Quite different from the 1m Curious Cable that I have been using for close to 2 years.  

The Lush definitely needs more time.  But mainly I need more time to play around and listen.  Just too darn busy right now! Have to flash, test, build, kit, and ship over 150 ISO REGENs and ISO REGEN/UltraCap LPS-1 bundles next week.

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11 hours ago, Superdad said:

 

It is interesting.  Still getting used to it.  Quite different from the 1m Curious Cable that I have been using for close to 2 years.  

The Lush definitely needs more time.  But mainly I need more time to play around and listen.  Just too darn busy right now! Have to flash, test, build, kit, and ship over 150 ISO REGENs and ISO REGEN/UltraCap LPS-1 bundles next week.

It seems I'm quite a lagger since I can't find an active USB regen thread : my apologies to jump in here :

 

After moving my DAC (turned that a so called audiophile stand could not stand the loud vibes I'm sending nowadays), for whatever reason, the DAC did not play right away. Trouble-checking I was shocked to be better off without the usb regen at DAC end ; however I preferred the SQ with the USB REGEN in, but at computer end.

 

it does not seem to make sense... are we talking tricks of my mind or is it possible though I know the regen should be at DAC side?

 

cable is certified Belkin, green second hand USB Regen unboxed, MeanWall, DAC is TEAC 501. 

 

About the DAC : begins to sound right after 3 days of continuous flow. I already noticed that it took about 20 minutes for the TEAC/Regen  combo to be good (I use a MBPr that serves other purposes so : plug/unplug...) : only explanation I can think of is that it would be faster/better for the TEAC to adapt to the global connection of the Mac/Regen/cable rather than to the connection of the cable/computer while it had reached equilibrium at its usb entry with the continuously on Regen (needs the 5V) but not fed by signal

 

does it make any sense ?

 

All the best Alex,

LCM

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Relative to the USPCB, there is a very slight smearing of the upper frequencies with the Lush.  High hats are crisper and more "right" to my ears with the USPCB.  Has anyone else noticed this?  And if so, might I expect further burn-in time to help?  I have only 5 days on the Lush so far.

 

(For my comparisons, the ISO REGEN was left feeding my DAC via a USPCB.  I swapped only what connected my microRendu to the ISO REGEN).

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