[rhodes54]

Quote:

Originally Posted by krisno /img/forum/go_quote.gif Interesting if your modded VALAB is better than your Benchmark. Is that running via USB also???

No, I use the Valab DAC through its Optical/Coax input only, same goes for the Benchmark. I don't need the USB input but it's a nice extra feature which can be handy in some occasions.

 

[shogo33]

Man, you guys are legends! I reckon someone here should(assuming they have time for it) to offer modding services for the Valab!..hint..hint!

Sounds like you guys have managed to take the Valab to another level altogether and reading on what works (very subjective to each listener) and what doesnt is great!.. Keep up the good work guys.

 

[mrdon]

My mods are now complete. I went with a mix of Black Gates FK & PK, Nichicon UPW & UPS, and one Elna Cerafine (oops) capacitors for power supply. For the outputs caps, I went with Black Gate 47uf/6.3V NXHi-Q's. Stock diodes were removed and replaced by Schottky 11DQ10's. The stock 390R I/V resistors were replaced on the under side of PCB with Kiwame Carbon Films. Lastly, I experimented by soldering two twisted teflon coated silver wires b/t the output capacitors and the output RCA's. Sounding very, very good - gobs more detail, air, bass slam.

 

[PatOMalley]

very nice, mrdon, as usual.

more detail with the teflon silver? I have some teflon copper. may give that a try. These pictures always provide incentive.

 

[mrdon]

Quote:

Originally Posted by PatOMalley /img/forum/go_quote.gif very nice, mrdon, as usual. more detail with the teflon silver? I have some teflon copper. may give that a try. These pictures always provide incentive.

Thank you for the complement. Yes, I try to make sure all the passive parts fit nicely and look good. In fact, that is one reason why I went with the Black Gate NX's instead of film caps.

More detail with teflon silver - absolutely. In fact, I like it so much I am considering upgrading the signal path of my Cambridge 640P phono stage with the teflon silver. Oh, wait that's for another place where you and I hang out.

 

[rhodes54]

Friday morning I was very excited when finding all ordered parts in the post at once.

I just decided that it would be a weekend producing in my studio but one look at the packages and I changed plannes. It was time to update my Valab spaceship!

Tonights Setup:

The parts ready enter the spaceship:

Finished Close Up 1

Finished Close Up 2

Finished Overview

Unfortunately I didn't manage to solder the LT1084 with its heatsink from the board. I only had a hand vacuumpump at hand and it wasn't able to suck all the solder. I'll give that another try on monday at work where we have a professional desolderingstation.
These updates have been done tonight:
- Caps Mod: The power supply will be updated according to Bill's mod: 3x 1000uF BG FK's, 1x 220uF BG FK and 8x 47uF BG FK's for decoupling of the DAC chips. 8 Sanyo Os-Cons SP (low ESR) 100uF/20V will replace the caps in the digital circuit.
- 4 Vishay 11DQ10 Schottky Diodes will replace the original ones on the board.
Will be done later:
- Power supply upgrade. A 30VA toroidial transformer will come in place of the original one.
- The LT1084 will be replaced by the DEXA 7808 to reduce noise generated by the LT1084 (Attention: This requires rewiring of the DEXA as the pin-out is different).
- The 330R resistors of the I/V stage will be replaced by 340R 0,1% metal films for now. (might need to experiment more with different type of resistors)
- The Coax/Optical switch will we replaced by a relay so I can switch it from the front without extending the digital signal line all the way through the case.
- Last but not least I bought a nice Galaxy Maggiorato case at HIFI2000.it where the Valab will find its new home because the Caps & Transformer ain't gonna fit. Besides that I want to get rid of the cheapo look of the original Valab case. The Hifi2000 cases aren't expensive, have a good buildquality and look very nice.

Will update the rest later.

 

[rhodes54]

Friday morning I was very excited when finding all ordered parts in the post at once.

I just decided that it would be a weekend producing in my studio but one look at the packages and I changed plannes. It was time to update my Valab spaceship!

Tonights Setup:

The parts ready enter the spaceship:

Finished Close Up 1

Finished Close Up 2

Finished Overview

Unfortunately I didn't manage to solder the LT1084 with its heatsink from the board. I only had a hand vacuumpump at hand and it wasn't able to suck all the solder. I'll give that another try on monday at work where we have a professional desolderingstation.
These updates have been done tonight:
- Caps Mod: The power supply will be updated according to Bill's mod: 3x 1000uF BG FK's, 1x 220uF BG FK and 8x 47uF BG FK's for decoupling of the DAC chips. 8 Sanyo Os-Cons SP (low ESR) 100uF/20V will replace the caps in the digital circuit.
- 4 Vishay 11DQ10 Schottky Diodes will replace the original ones on the board.
Will be done later:
- Power supply upgrade. A 30VA toroidial transformer will come in place of the original one.
- The LT1084 will be replaced by the DEXA 7808 to reduce noise generated by the LT1084 (Attention: This requires rewiring of the DEXA as the pin-out is different).
- The 330R resistors of the I/V stage will be replaced by 340R 0,1% metal films for now. (might need to experiment more with different type of resistors)
- The Coax/Optical switch will we replaced by a relay so I can switch it from the front without extending the digital signal line all the way through the case.
- Last but not least I bought a nice Galaxy Maggiorato case at HIFI2000.it where the Valab will find its new home because the Caps & Transformer ain't gonna fit. Besides that I want to get rid of the cheapo look of the original Valab case. The Hifi2000 cases aren't expensive, have a good buildquality and look very nice.

Will update the rest later

 

[awkwardbydesign]

Hi, first post, so forgive if I am asking stupid/repeat question.
I have the latest (I hope) 2009 Valab DAC, just bought 390 ohm Audio Note tantalum resistors, and 220uF BG FK.
Before I start changing the output caps I will try bypassing the stock pair. My question is, do polystyrenes work? I have loads of them, up to 33000pF in value. Also 10uF polyesters, polycarbs, 2.2uF Siemens polyprops, enough to parallel them. Any advice?
The CD player is a Shanling CD-T100, first version, the Valab is an improvement.
By the way, I find that making better mains leads is always a big improvement.

 

[PatOMalley]

awkwardbydesign,

The Audio Notes Tantalums are magnetic. I would forgo those. Partsconnextion has Shinkoh Tantalum which are NOS and non-magnetic.

If I was doing it over I would have kept the original caps and bypassed them.

 

[awkwardbydesign]

Thanks Pat, I should have thought about the magnetics. What about polystyrenes as bypass caps , though? I get too tired these days to try things over and over again ( long hours and age don't mix well).

 

[PatOMalley]

awkwardbydesign,

Never used polystyrene's so I can't recommend them. I know I do like the Obbligatos .... bypassed /w Teflons. I now have Obbligatos bypassed with teflon on the phono pre and dac. The line pre has Jupiters bypassed /w teflon. I am going to recap a set of EPIs /w Obbligatoes bypassed /w Teflon. Get the picture?

mrdon,

Very nice improvement. I use Teflon coated solid core 6N copper. Not as malleable as soft annealed silver. It's amazing the response the DAC had to this little mod. I think if I rate these mods it is the output caps, the DIR9001 mod, and this output wire that has had the most positive impact.

There is a anecdote that when Persians weaver rugs they weave a mistake into the work so as not to pretend to perfection and insult the gods. In this same sense but without forethought I reversed the left and right channel. No biggie, it is just to color coding on the RCAs that give it away. I did the same thing on my SUT. It is my signature.

My frontal lobe gets in my way. Which is why it is such a pleasure to see the nice work you guys do.

 

[shogo33]

Just received mine today. So far been listening to it for about an hour. Compared to my old Sony X55ES via analog out, the Sony's sound is smoother and is very laid back. The Valab is much more punchier with the bass with excellent details to the upper end and soundstage! So far, I prefer the sound of the Valab, but I cant wait till this burns in for around 200hrs+..

Might try it with a glass toslink instead of the plastic fiber cable that i'm using.

 

[rhodes54]

Last friday I received all my ordered parts for the next mod round. I tried to post some pictures of the modification with a nice story but the message got rejected for some unknown reason so I lost my complete post.

The (almost) fully modded Valab is burning in again and it sounds great! I will rewrite the complete story soon, hopefully it won't get rejected by the board this time...

By the way, I have a hard time finding out which Toslinks are real glass. Can anyone give me manufacturers which make real glass toslinks? I know Audioquest has one, The Optilink-5, but that's the most expensive one ($200+) in the series, the rest is made of polymer.

 

[shogo33]

Btw, just out of curiousity, does your Valab power supply hum or emit a low buzzing noise that can be heard about a foot away? Mine seems to be doing this. I've narrowed it down (by just powering the dac directly to a power socket at the wall) and swapped the power cables to different ones and the noise is still there. I've even plugged it around several power sockets around the house to see if it made a difference, but it didnt.

I've sent Kevin an email about this, but he hasnt replied back. I hope the power supply unit isnt faulty, but its hard not to suspect it as the hum/buzzing noise seems to be coming from it.

 

[dannie01]

I have finished finally, thinking not to mod anything in the meanwhile, it really fun in the process but tired. See below pic the final mod of my Valab 2009.

BTW, I have to thanks Bill, Pat, Phil and many many other members here. The Valab sounds wonderful like that is far from my expected.