[r8833]

mrdon,


check with michael at Teradak he designed the Dacs

Rich

 

[rhodes54]

Quote:

Originally Posted by dannie01 /img/forum/go_quote.gif rhodes54, pic of the Valab's new home, the "Dreamdac" please. How much you spent on modding, Tentlabs XO Clock , new home and may be cryo treatment.............triple of the original cost? Head-Fi, really an Evil website.

I will post pictures as soon everything is finished but I can show you the design of the frontpanel:



The big circle will be a switch for selecting the optical or coaxial input. Orange leds above I & II will show which input is selected.
I will use 3mm diffused flat-top leds. I personally like this the most.

I haven't calculated the total costs of the DAC yet but it will indeed be aprox. triple the costs. This looks like a lot of money but after doing all these mods you'll have a DAC equivalent to DACs in the $2000 - $3000 range, if not more.
So far I listened to a heavy modded Benchmark DAC-1 (Total costs over $2500) and the modded Valab easily blows it away on most points. I even decided to put my Benchmark for sale now.

@ Bill: I think $75 minimum is a very reasonable price. It's almost cheaper for me to send the DAC to the US in stead of doing it in Holland. I'm waiting for a quote from one more company.

@ mrdon: As I wrote a few posts earlier an external clock will work on every digital circuit. The biggest problem will be the how to assemble it into the case of the 2008 version of the Valab. If you are a bit creative it won't be a problem

@ Dubai 2000: It will affect the USB input as well because the print will reclock the signal in the last stage of the DAC, just before the Digital to Analog conversion will take place.

 

[dannie01]

Sorry, double post.

 

[dannie01]

Shamed on my case compare with yours. I have it drilled few holes only and that's it. But I do love it's sound very much. Cheers

 

[dubai2000]

@rhodes54

thanks for the info. Do you have the 2009 model and would you (or anybody else) provide info on how to install the new re-clock board?

 

[dannie01]

See this LINK from Michael of Teradak for the installation method.

 

[rhodes54]

I dropped a mail to Michael yesterday to ask him a few more questions about the clock and the power supply of the Valab.
I wanted to be 100% sure that the LT1084 regulator is dedicated to the Dac chip board only. His answer contained nice news for us:

"The Lt1084 is dedicated for the TDA1543, which consume much current. Actually, we are designing a power box for our existing customer upgrade. We are preparing R-core transformer and the external box."

After all our modifications the power supply is one of the few weak points left. If Teradak is indeed able to design a decent low noise power supply it would be the last (big) step up.

 

[dannie01]

That's another great news other than the re-clock which offered by Michael to make this little monster sounds better. Accumulated all mods exist currently, I have never try to have such fun in modding a device like this one and each mod is surprising, really appreciate for all of you to share your experience and expertise.

 

[dubai2000]

@dannie01

thanks for the link - looks simple

.

 

[Bill Allen]

Diyhifisupply has some very nice looking cases for moving our Valab Dac boards and large film caps into.

Projekt X Parts | Diy HiFi Supply

The middle sized one looks about right.

 

[PatOMalley]

Bill,

I looked. I was tempted. But the Obbligatos + Russian teflons [let's not mention the BGs on the bottom] sound so good that the work effort, I fear, will be a side step rather than a step up. So I just window shop. But the super regulator, that I will pull the trigger on this coming week. Feed better power to the DIR9001.

But that chassis is nice. The one thing that bugs me about an outboard case for the caps is that how do you get back in to the main chassis with the cap leads in the way now?

 

[Bill Allen]

Pat- I drilled an extra hole in the back plate and ran the wires through them. This allows me to lift off the top cover to get back inside the case. Obviously this is not my final solution ... time will tell what that will be. Still working on battery power supply and dreams of transformer output are still dancing in my head.

A better voltage regulator for the "input side" of the board should help lower some jitter. Same goes with the Dac board power supply regulator. Separating the power supply delivery to these two regulators would also be a big upgrade. Perhaps a new dual output transformer, say 12-16 volts for the Dac Board and 8-12 volts for the input side. Of coarse you would also need to add separate power filtering caps for the input regulator. All good.

And the hits just keep on coming!!!

 

[meusickfrek]

any thoughts on what would be the best combo, Obbligato .22uf with the stock 10uf russian cap, 4.7uf obbligato as a single coupling output cap, or a 4.7uf obbligato bypassed with a .22uf obbligato, I kind of like the idea of adding just one cap but if it's worth it soundwise I'll add two...thanks for any input.
Any other combinations or mid-range($) cap suggestions will be appreciated, and yes I did read this thread twice so thanks to all who contributed.
PS I just bought a $50 soldering station and I've only soldered like twice in my life.....

 

[mrdon]

And to add just another mod possibility...a tube output stage from Welborne Labs.

 

[Bill Allen]

meusickfrek-

There is no easy answer to this question; the simple answer is to simply bypass the stock cap with a .22uf of higher quality. Maybe even bypassing that with a .01 Russian Teflon like Pat did.

I said it in the past and I will say it again; changing the I/V resistor and coupling caps is like adjusting bass and treble. This is not what you are actually doing but the net result sounds similar. This is very system dependent.

For example I would not want to add a tube output supply to this Dac, here you would be missing the point completely. Simplicity is the path to accurate sound and that is what you want from "your source". Think of this like starting with pure clean water, there are plenty of ways to flavor the sound post the source if that is your bag. (And when I say flavor I not saying that in a derogatory way, I myself run a single stage tube preamp and SET monoblocks).

The purity of your power supply, I/V resistors and coupling caps play a huge role in how "your system" will ultimately sound. You get what you pay for here; however the best caps on the planet will not help a poorly balanced system. Remember if you start modding the Valab Dac you are now the engineer. This is a "hard path" to start down, but ultimately it's a way of life that every audiophile needs experience for himself.