Just picked up another Biacrown DR 504

[philmanatee]

I traded a couple guitars I wasn't playing for another Biacrown DR 504. This one is a little earlier than the one I gig with, it has toggles instead of rocker switches. I haven't tore into it yet but i think it may sound better than my other one. I've been playing it for the last hour through a bassman cab loaded with two Fane AXA-12's, it really kicks! I can't wait to get it to my practice place and compare it with the other one through the full stack. Does anyone ever run out of the slave out into another head? I was just wondering if that would work. Phil

[OldSchoolDave]

I traded a couple guitars I wasn't playing for another Biacrown DR 504. This one is a little earlier than the one I gig with, it has toggles instead of rocker switches.

Partridge transformers, by any chance?

Dave

[philmanatee]

Nope, it's got the Drake's.

[philmanatee]

It's kind of funny I've got a Laney and an Impact with Partridge transformers, but both of my Hiwatts have Drake transformers. Phil

[OldSchoolDave]

It's kind of funny I've got a Laney and an Impact with Partridge transformers, but both of my Hiwatts have Drake transformers.

What's wrong with this picture ?

Unless one of your Biacrowns has the OL mod and the other doesn't, I'm not sure what would account for the difference. Maybe just the valves?

Dave

[philmanatee]

I probably won't get to compare them for a week, our bassplayer is out of town an that's where the other one is. Phil

[philmanatee]

The new one definitely sounds sounds better. I brought them both home so I can compare. Phil

[philmanatee]

I just popped it open, it's got some messy mods. The preamp board appears unmolested although some of the extra caps have been tapped into it at one point. It has the stock OL on V2 which looks to be slightly modded and they've added a stacked master volume pot. V2 is using a 12AU7, which is probably one of the reasons it sounds smoother than my other one. The inspection sticker says 83 so it's closer in age to my other one than I thought. I'm going to try to replicate these mods in the other one because this one sounds so much better, plus my other one had already had some crappy mods done most of which I've removed. Phil

[OldSchoolDave]

V2 is using a 12AU7, which is probably one of the reasons it sounds smoother than my other one.

That's a pretty big drop in gain (100% for a 12AX7 vs. 19% for a 12AU7). Odd they'd OL it and then back off the gain .

Get 'er closer to stock and try 'er again.

Dave

[philmanatee]

There are a bunch of extra caps added in a few places, it's going to take me a while to figure out what's going on. Phil

[mhuss]

Let us know once you figure it out.

-- mark

[philmanatee]

I've got a friend coming over tomorrow that is going to help me figure it out. It's got more filtering added in the preamp. I think I'm going to play it some more! Phil

[Zells]

Please post some photos. Stop being a tease to us amp nerds.