[jlafrenz]

In all my indecisiveness between SS and tube pre vs. integrated, I pulled the trigger on an Antique Sound Labs AQ1003-DT. It was one I wanted to try and the price was too tempting. So far I like it, but want to fine tune it just a bit with some tube rolling. It uses 12AU7's. Right now it has Mullard CV4004's and JJ's for the pre and driver tubes. I am looking for a bit more lush/intimate sound as well as a bit more depth in the sound stage. I found a quick summary of some options on AudioKarma and wanted to inquire about everyone's thoughts and suggestions here. I realize it is subjective and the best way is to try some tubes. I thought perhaps everyone could at least point me in the right direction or if there was anything close to a general consensus on some tubes.

http://www.audiokarma.org/forums/archive/index.php/t-181626.html

[Kim S.]

I have a ASL pre a AQ-2006 DT which also came with JJ 12AU7 tubes.  It was a significant upgrade when i swapped these with RCA "cleartop" tubes.  I forget how much they cost but I think a matched pair ran me about $50.  More expensive but also 12AU7 tubes i like are Amperex bugle boys and RTF.  I do't think you can go wrong with the RCA's.  I'm a big NOS tube fan.  One vender you can check out is Vacuumtubes.com.

[bunnyma357]

I looked at inexpensive altenatives for 12AU7 tube rolling.

In my Onix SP3 integrated, I've tried a lot of used 5814A's that tested well (RCA, GE, Sylvania, etc.) and they were nice sonically, but not "magic".  I finally settled upon East German NOS RFT ECC82/12AU7 as my favorite - really nice open and airy "live" sound.

http://www.tubedepot.com/nos-12au7-rft.html

Jim C

[JakeJ]

Hi jlafrenz,

OK, FWIW, I dismissed the thread you linked to as soon as I realized they were talking about the Bottlehead Foreplay.  Why?  The circuits are too dissimilar.  In my experience you need to have references that are directly related to the ASL AQ1003 DT and no other device or it's tube rolling references will apply.

For example I quote LDR's post from 08-31-2008, 07:50 PM"Amperex 12AU7 (Heerlen factory): excellent tube top to bottom. This one does it all." This tube may sound thick and syrupy in the ASL AQ1003-DT.  Tube rolling is very circuit dependent.  You might contact ASL and ask them if they have any suggestions for NOS or other tubes than stock.Did a quick Google and this link came up for the amp over at AudioKarma:http://audiokarma.org/forums/showthread.php?t=194608
About three quarters of the way through the owner switched to ElectroHarmonix for the best sound compared to stock or NOS Brimars and RCA cleartops.  Totally contradictory of findings in the Bottlehead Foreplay thread.

[jlafrenz]

I have a ASL pre a AQ-2006 DT which also came with JJ 12AU7 tubes.  It was a significant upgrade when i swapped these with RCA "cleartop" tubes.  I forget how much they cost but I think a matched pair ran me about $50.  More expensive but also 12AU7 tubes i like are Amperex bugle boys and RTF.  I do't think you can go wrong with the RCA's.  I'm a big NOS tube fan.  One vender you can check out is Vacuumtubes.com.

The Cleartops are some I wanted to try just to see what the all the rave was about. I have some Amperex in various other components I have been pleased with.

Hi jlafrenz,

OK, FWIW, I dismissed the thread you linked to as soon as I realized they were talking about the Bottlehead Foreplay.  Why?  The circuits are too dissimilar.  In my experience you need to have references that are directly related to the ASL AQ1003 DT and no other device or it's tube rolling references will apply.

For example I quote LDR's post from 08-31-2008, 07:50 PM"Amperex 12AU7 (Heerlen factory): excellent tube top to bottom. This one does it all." This tube may sound thick and syrupy in the ASL AQ1003-DT.  Tube rolling is very circuit dependent.  You might contact ASL and ask them if they have any suggestions for NOS or other tubes than stock.Did a quick Google and this link came up for the amp over at AudioKarma:http://audiokarma.org/forums/showthread.php?t=194608
About three quarters of the way through the owner switched to ElectroHarmonix for the best sound compared to stock or NOS Brimars and RCA cleartops.  Totally contradictory of findings in the Bottlehead Foreplay thread.

I know that link referenced the Bottlehead, but it was one of the few resources I found that gave quick comparisons of the tubes compatible with the 12AU7. I by no means think it is a standard reference. That is why I posted here inquiring about suggestions for my specific amp. As you have already stated, I have also discovered in my reading that different tubes will act different within different circuit designs. That is about as far as my knowledge goes with this. I did a quick read on through the link you posted. It mostly talks about the EL34 tubes, not the preamp tubes in which I am currently interested in. He does state that he liked the the EH tubes over NOS, but didn't give much of a reason why or what they did better or worse than other tubes. Just his preference and he may be looking for something else performance wise from the amp than I am. I think I will take your advice on inquiring with ASL directly to see what their thoughts are for replacement tubes.