NAD: CJ's Cavalcade of New Smallish Cheapish Amps - #1

[culturejam]

Just finished a 20-minute tube swap listening test. For the preamp: JJ 12AX7 vs JJ 12AT7. For power: Sino 6V6 (stock) vs JJ 6V6 vs Tung-Sol 5881 (vintage). I tried all possible combinations of tubes.

I definitely preferred the 12AT7 in the preamp with all of the power tubes. It's the only way to have clean headroom above conversation level. If you are looking for a 5W "exploding amp" sound, definitely go with a 12AX7. I may try a 12AU7 as well and see how that sounds, but the AT7 will stay put for now.

The Sino 6V6 is a fine tube, honestly. Very middle-of-the-road tonewise and gain-wise. I wouldn't hesitate to use this brand in another project.

The JJ 6V6 was my favorite of the three with humbuckers. It breaks up the latest and has a little less bass than the 5881. Sounds nice and clear with the AT7 (which cuts a little off the high end).

The Tung-Sol 5881 was also nice, especially at mid to upper-mid volumes. Didn't sound as good wide open, which is probably because it's getting less than optimal voltage on the plate. Or maybe the OT is getting maxed out (it's not very large). But with single coils, it sounded pretty good all the way up, and exceptional at middle volume (which, honestly, is where I'd be using it).

So for general use, I'm sticking with the 12AT7 and JJ 6V6. Great combo. FYI: I tested with a PRS Custom 24 SE and the cab was a Blackstar 4x8 (closed back). The combo cab is just really boxy sounding.

I think adapting an existing single-ended amp from 6V6 to 5881 (with proper changes to bias resistors and perhaps a more appropriate primary impedance) would be a worthwhile project. You get a little bit more headroom without a substantive increase in volume.

[Leevibe]

A 5751 in the preamp might be worth a shot too.

[culturejam]

A 5751 in the preamp might be worth a shot too.

Good call. I actually have a few so that's something I'll put on the list.

[junkemail86]

The Laney versions I repaired had the same problem. The amps would shake themselves to bits. The store I was doing repairs for dropped the Laney line but if I recall once I reflowed the sockets I don't think any of them had issues or came back in again.

Awesome. I'll also reflow the preamp socket pins just to be safe.

BTW, I just plugged this into my weirdo Blackstar 4x8 cab, and it sounds so much better. I mean, that's hardly surprising. Kinda makes me think I ought to just build a small head shell for it and toss out the combo cab. Or maybe first try putting a 10" in there.

I feel like these low wattage tube amps are almost always more functional as heads (even though they typically come with a small crappy speaker).  I guess if you need a lightweight combo the internal speaker option is nice.

[thesmokingman]

definitely the case for the new version of the micro crush ... absolute junk internal speaker but you plug that into a cabinet and it is a whole lotta amp for 3 solid state watts

[Leevibe]

N the other hand, I had a Fender Pro Jr that sounded its best through the stock combo can with ceramic 10". I kept trying it through bigger cabs and I always went back to the stock speaker. That was a cool amp.