The Zero MOD Thread - 24/192 DAC/H/Amp

[Pricklely Peete]

This subject line has been a long time in coming. Hopefully the creation of which will alleviate the load on the reader having a thread with 700+ posts to wade through for the latest ruminations on tweaks, mods of all stripe etc....


Please post related ideas, tweaks, mods etc...in this thread.



Peete.

[Pricklely Peete]

I guess I'll get the ball rolling with the BA cap mod for the HDAM module.

Simply put it's a 1uf film and foil cap (PIO Russian K42Y-2 160V in my case) of 50V rating or better connected parallel to the V- and V+ pins on the HDAM module.

Here's a pic showing the solder points on the LC module (Lawrence Chan's first generation "Earth" module).









Please note second generation HDAM modules from audio-gd are far easier to add this cap to because of the pcb assembly of the units exposes good pad areas where the V- and V+ pins are located. The third pic shows BA's drawing of the HDAM pin outputs.

The V2 revs of HDAM have caps tied to gnd, 1 cap for each channel. It has yet to be determined if removal of these in favor of a PIO and hooked up the way BA suggests is the way to go....as always these things take time to compare and it is being looked at.

Peete.

[sennsay]

Onya PP, who's going to be a happy FrankenZero owner soon then! ME, and I'm looking forward to it. Please put your feet up now with a nice glass of something and sit back, won't you. Well deserved indeed, mate.
Many thanks for all your work, S-Man

[Currawong]

One of the suggestions by ccshua was to solder the earth wire from the HDAM to the RCA earth leg. I'm guessing this fixes some or other issue with voltage or current as the sound becomes more punchy and clear.

Since I use the Zero only as a DAC, I unplugged the head/pre amp as it was a waste of energy not to. Didn't notice any significant change in SQ as a result though.

[Pricklely Peete]

Agreed Currawong I have now soldered the DAC HDAM's ground wire to the RCA jacks ground.

I haven't noticed anything (when unplugging the H/Amp power connector from the main pcb) other than the voltage regs on the main pcb are now quite a bit cooler than before.

Sennsay...thanks man !!! It's been a crazy 24 hours around here

Peete.

[Pricklely Peete]

This is a mod to isolate the Zero's Headphone amp from the stock power supply and transformer (allowing use of HDAM modules in the H/Amp opamp sockets)

It's a wee bit expensive and not very practical for the average Zero owner but it certainly does allow for the full use of the 3 HDAM config with great results.

Personally I opted for this mod because I felt the H/Amp section could be improved by giving it it's own highly regulated power supply (plus 50VA transformer)

The PS1 kit is DIY from Welborne labs. All specs and such are located at the web site. I'm running the reg board at -15 0 +15V DC as per the spec for the Zero's head amp requirements. Current is limited to 1.5 amps at this time but the board can easily scale to 3amps with a transformer swap.

Here are some pics of it's construction and it's use with the FrankenZERO.








The Head amp has considerable balls now......the whole mod is still in burn in from extra modifications I added ( 8 bypass caps on the reg board) and 4 more bypass caps on the Head amp's beefed up electrolytic caps. Power supply caps were swapped from 330uf 16V to 1500uf 25V Nichicon PW's. The 47uf 10V Silmic caps were swapped for 47uf 35V Elna Silmic II's (both sets of these bypassed with .047uf 160V PIO) The same PIO's were used to bypass the 8 reg board caps.

I would say for 95 % of the Zero owners this mod is for the die hard cost no object type of person and I don't recommend anyone doing this mod unless they can source far cheaper options than the PS1 kit. It certainly was fun doing this modification. The whole Headphone amp has to be relocated into another chassis which adds even more cost to this mod...all told it makes little sense cost wise.

Peete.

[LeBuLLeT]

Peete do you think that PS1 kit mod was worth the sound in upgrade? Do you think it would just be better to get a separate head amp?

[Pricklely Peete]

Originally Posted by LeBuLLeT

Peete do you think that PS1 kit mod was worth the sound in upgrade? Do you think it would just be better to get a separate head amp?

I think that money is better spent on a dedicated amp. I only included the PS1 mod because I had done it......for those not able to buy a dedicated amp the PS1 mod could be a good solution.

It was an experiment to see how far the Zero's Head amp could be taken. It's better for sure with the PS1 mod, as good as a dedicated amp (like the MK III which cost an additional 150US) is debatable. With the new LD I+ for instance the PS1 mod makes very little economic sense.

My idea was/is to create a one box solution aka FrankenZERO SST for the cottage (using 3 HDAMs) with a traditional CDP as source (heavily rebuilt and modified as well). Space for my stuff is an issue and I need a compact setup when heading to the lake every summer.

Peete.

[Pricklely Peete]

C'mon guys without end user participation in this thread it's useless....start posting your various mods and ideas please.

Peete.

[majkel]

I guess all mods were posted in another thread. People won't be willing to repeat. BTW do you find Silmic II sounding better than Silmic? I don't, at least where I tried. Silmic ROS is more natural than RFS IMHO.

[PyrotekNX]

This is closest to the DIY section, so I will have to post it here. I was replacing my broken TOSLINK connector the other day, and I think there was a bridged connection. The mosfet in the left rear closest to the power plug got very hot to the touch, and the LEDs in the front panel were not lit. I cut the bridge, and the LEDs came back. Now when I plug in the TOSLINK or the digital coax, the signal LED on the board does not light, and I am not hearing the click I usually get when the board senses a digital signal. Anyone have any idea what might have fried? I did not see any sparks, and there wasn't a short as far as I know. Everything seems to power up fine, except for the digital input.

[bundee1]

Anyone have pictures and tips on how to do the alps pot mod? I got mine and was wondering how to remove the blue casing.

[Currawong]

I just realised you posted this in the main Zero thread, but I'll post my reply here too: You need the model from Lawrence (the Zero seller). The regular blue Alps pot wont fit and the casing can't be removed.

[Pricklely Peete]

Swapped out the crappy digital coax in for a CMC jack and some silver wiring

Tough to say if it's better SQ overall but I'm sure it can't hurt....an easy tweak for sure

Heres a pic of it in use.....





Peete.

[StratCat]

Originally Posted by bundee1

Anyone have pictures and tips on how to do the alps pot mod? I got mine and was wondering how to remove the blue casing.

Bundee1 -

IIRC, you ordered the pot with the square blue housing, like this ALPS RK27 Series

The pot I just received from Lawrence looks similar to this VRA-100S100

(But it is labelled ALPS 820G 100KAX2)

Mine looks similar to the one Penchum used in his ALPS upgrade. I'm not sure if yours will fit (but hey, give it a try). If it doesn't fit (and you don't mind risking destroying the pot) there might be a way to remove the blue housing, but I have no idea if that'll destroy the pot or not.

If you have the correct pot it's a simple R&R direct replacement job. I'll be replacing mine soon, and will try to get some pics and post here, but can't give a specific time frame other than "soon" (read: soon as I get time and am not too lazy).

Good luck.

Edit: Ahhh...just seen you are well advanced with this now in the main Zero thread...oh well, this thread gets a free-on-me bump!