Valab NOS DAC - subjective listening and modifications - Page 116

I think Mikes talking about his valab 3

the 2.1 dac does not even have the inductor im talking about. Your refering to the 2 inductors in the "Low pass filter" those are not required. There is actually an inductor that connects the Main PCB to the DAC board. It can be seen on the 2.5 dac and higher. It's got nothing to do with the output.I tried bypassing it with silver wire and it did not work. It can be seen below.

BTW an inductor is not measured in Ohms (unit ofr resistance) but in Henry or rather milliHenry (in this case), asking for a 1 meg inductor might just solicit a 'we keep them with the drills for square holes' response in an electronics shop ;-)

Pat if you do not hear any saturation noises (loss of bass/loss of detail/ high distortion)you should be fine as it is quite impossible to burn them trannies with this sort of micro power.

Thanks Mike, That inductor looks fine. The 2 that I removed (from the output filter) measure about 25 ohms. I have no way to measure inductance. When I meaure this single inductor (with ohm meter) I measure about 720 ohms. You mention 1 Megaohm so I guess it's OK.

I received my TXs today :-)

Guess I have to sort the volume adjustment of my amp soon as I'll not be able to assess the improvement properly with a clipping amp.....

Marcel, How long did the shipping take to arrive? I'm waiting for 2,5 weeks now and I'm starting to get a bit worried because there are 26 resistors on its way. Normally a package from the States takes 7 to 10 days...

I ordered them about two weeks ago (think the order was finalized on the 26th), in the confirmation mail I was informed they expected ship date of the 9th of Feb.
The envelope was stamped on Feb 5th.

Just ask them, I found doing business with TX a warm bath!

Possible help

If you are getting massive distortion you may simply have the wrong resistance for the I/V conversion. You may have partially shorted the resistors during the mounting process. They are "nude" and the adhesive may be hygroscopic and for sure the wood is. Measure them again as installed if you have not already.
I have the Dueland's and my Chameleon mounted in one large box. I used solid silver wire with cotton insulation (from VH Audio) to connect them. If you do not notice any RFI then don't spend a bunch on cable to get rid of a problem that does not exist. Buy a nice aluminum box on the web which will help keep out RFI and it will reduce the dust and other crap from getting on your internals of the DAC.

I totally agree with you. I ordered there before. Im just afraid that the package got lost in the post.

Anyway, I'm very curious what you think of them. As I wrote before: I fell in love with them

I will probably be able to put them to work on Friday, will definitely solder them point to point as I have heard the difference in SQ between a pcb and hard wired.....

I'd contact TX to hear what type of package they sent and with whom and when, a parcel using UPSP might take a while.....took them 5 weeks to deliver some sunglasses once...

i have a question about changing the 8 capacitors on the dac chips, stock valab has 10uf surface mount caps there, i remember Bill switched them with blackgate 47uf caps. My question is, why not just leave the original caps there and solder the new ones in parallel with them. What would the effect of that be?

depends on the Quality of your bypass, but I plan to do exactly that using some MKP or MKS film caps before I take of the smd stuff.

Yet taking the smd caps off is driven by the fact that I do not trust the SQ of stuff I can barely see(so far that has proven to be right though), I like huge paper in oil capacitors and all that ;-)