What tubes and power cord on the Audiologic 24MXL?

From what I understand, this DAC is pretty transparent, as an old reviewer friend of mine has/had the latest version.

I sent him 3 sets of high quality 6dj8/6922/7308 type tubes to try a while back:

Mid 60's Tungsram(red print), 60's 6922 Siemens(S&H), and a set of Amperex 7308 white label PQ's from 1969.

The Siemens were transparent, clean, and extended, with excellent soundstaging and a quick midrange.

The Amperex had awesome bass and dynamics, with a textured midrange and decent highs.

The Tungsrams had a killer midrange, excellent bass, and a sweet/ever so slightly rolled top end, just a tad mind you.

He kept the Tungsram tubes, which were the cheapest of the bunch, and sent me back the others.

From what I can gather, tubes do make an audible difference with this DAC, as it is very transparent. This of course also depends on your systems transparency, and your own ears.................

I think you answered your own question, George, in that the type of tubes you use in this DAC is highly subjective, according to your sonic tastes and your system synergy.

I have found over the years that many tubes types(Siemens, Amperex, Phillips, Valvo) have identifying sonic characteristics, providing they are made at the same plant, around the same time, and of the same quality(noise, matching, etc.)

I would wait until you have the DAC, let it break in if needed, keep it in your system with the stock tubes, and become acclimated with its sound, in your system.

Then, decide where you would like to go from there. If you are up on tubes[6dj8/6922/7308 types] you
should know where to go from there, in matching the right tubes for your tastes and sonic priorities.

If you are not up on tubes, you can always do some research.

Rolling tubes can be alot of fun, for sure!

I cannot remember the type of power cord that he was using, but man, one could go on and on about PC's!!!

Best, Bill M.

I had the same dac and tried the Siemens and the Amperex and, in my system, the Amperex 7308 PQ's were the best choice. Bill give a perfect description of those 3 tubes , and I think those are probably the 3 best tubes for that dac. The nice thing about the Audio Logic is you can adjust the sound by tube rolling it. By the way, we both used Silent Source Signature power cords with the Audio Logic.

I have the 34 DAC so it is a little different using four tubes. I am using Amperex 7316 PQs and Amperex 6922 PQ Goldpins. I have used Bugle Boys, D-Getters and Orange Labels but the 6922s really added more bass, cleaner/clearer detailed sound, different mid-range not as dark sounding and more dynamic then the D-getters and Orange labels. Each tube changed the sound slightly but the 6922s were more of a change.

Hope this is helpful.

As mentioned in another thread, I like Telefunken and Siemens Ccas in my unit--the stock Sovteks kept going bad too fast. They seem to give a balanced sound to the unit overall, and I've always liked the Telefunken sound anyway. For power cords, I have used the K-Works Empowered and Dynamo cords and the TG SLVRs, all work very well with it. The Dynamos were noticably better in the reproduction of transients, which surprised me a bit, as the TGs and standard Empowered Cords were hardly slouches in the area.

Thanks for the responses.

How long did the dac take to break in?

I am finding it is much cleaner than my Electrocompaniet ECD-1 in the midrange and highs, but that it is light in the bass dept.

This unit has about 60 hours on it.

George

It does take a while, if the new unit still uses the MIT Multicaps that the 34 and 2400s did--they take forever, seemingly, to break in. Can't tell you with my unit, which was a demo, though it still needed a few weeks after I got it even after having been on at the dealer's for a good time. It is not the absolute world champion in terms of apparent bass, probably, but I get more than enough from mine, extending to 20 Hz and below and not at all boomy or bloated. If it doesn't improve over the next few weeks you might call Jerry about it, but it sounds like you just might need a bit more break-in.

Well, I bought the dac. :-)

Now to get some tubes...

Thanks for your help.

George