PPIMV for Blues Jr.?

[The New Steve H]

Factory amps are cluttering my life. I have to man up and do something. Improve them or sell them.

I like my old Blues Jr., but I do not gig (I am not that cruel to music fans), so I never need to turn it up. I changed one or two tubes to make it sound nicer. It would be useful if it had a PPIMV or other volume control on it.

Wondering: has anyone tried adding a low-volume control to one of these things, and is it worth the effort?

[The New Steve H]

Also, where is the malware I was promised? I see no sign of it.

[rp]

FYI, if your unfamiliar, this guy dedicated his life to modding Blues Jrs lot of info for endless pcb fun. not sure if there's anything on adding a MV.

http://billmaudio.com/wp/

IME MVs on large amps work and are good in reasonable doses, just to knock a couple dbs off. on small amps they just make it sound like a $100 ss practice amp, actually worse as a decent ss practice amp can be very nice, and they tend to stay bright when squashed down. MVs work a bit better on amps w/ no NFB, don't know how the BJr is set up. OTOH I don't want to discourage tweaking so go to it.

Also, where is the malware I was promised? I see no sign of it.

Dang Pakleds, somehow you are blessed? What are you doing right? Could it be it's gone an the rest of us have some stupid cookie or something putting up the flag.

[The New Steve H]

Thanks for the link. It turned out I had a PPIMV sitting around, already wired up. I stuck it in the amp, and it sounds very nice.

This amp does not seem great for clean tones, however. I can't recall if that was always the case.

[The New Steve H]

I knew about the Bill M mods, but I never paid much attention before. I didn't realize he had a way to get better clean tones out of it. Very nice. I will have to try that next.

[The New Steve H]

ANNNND I like it.

This is actually a very nice amp now. I don't think Joe Pass would want one, but it's sounding really good.

[Firestorm]

BillM is a crazy man, devoting his brain to gilding a cow flop. God bless him. But the amp is designed to eat tubes no matter what you do. When you could find 7189As, you could get away with anything, but you're more likely to find double getter XF2s now.

[Stevem]

Rebuild that jr Cow flop amp with a Hammond 1650F OT, and rewire the sockets to take 6973 output tubes!

[The New Steve H]

Is that a serious suggestion?

I don't know a whole lot about this amp. I got it in '97, when I was under the delusion that I was about to learn to play blues guitar. For most of the last 18 years, it has sat in my office doing nothing. I got an XD Super Champ or whatever the exact name is, and I got a little Vox, and I built my own amps, which pretty much destroyed my interest in making store amps work.

It sounds fine now, but if there are other problems with it, coupled with solutions, I would like to know.

[The New Steve H]

I can certainly see why people would question Bill M's devotion to an amp which obviously has issues, but I already had mine, so I figured I might as well fix it.

[sluckey]

If you have any interest in rebuilding a Blues Jr., you may want to take a look at this link. Hoffman rebuilt one with a turret board and provided good documentation for the project. He sells the boards and any other parts you would need.

http://el34world.com/Forum/index.php?topic=17873.0

[The New Steve H]

One of the interesting problems Bill M tackles is not one that would have been obvious to me: fragile pots.

The pots are tiny and weak. They're soldered onto the board, not panel-mounted. The shafts are so long, the knobs ride about 1/4" above the metal chassis. If you drop something on a knob, instead of pushing the knob against the metal, it applies force to the inside of the pot, possibly fracturing it.

Bill M's solution is to shorten the shafts so the knobs sit on the metal. Also, Fender sells plastic bushings that sit between the knobs and the chassis.

I ordered bushings and some nicer knobs.

[rooster]

Steve H, I have modded more than 50 of these amps, changing parts, trannys, etc., depending what the customer had in mind. I know Bill via early contact from the Fender Forum when he got started on the mods for the BJr. Haha, I never would have thought he would have become world famous for 'his' mods when this started because he knew absolutely nothing about electronics. His history was to simply ask folks on the Forum to design/create a solution to what was perceived as an overly bright amp. Many ppl contributed, myself included, and here we are.

You will find some useful things on his site, kits that you can order, that will help the amp. Here are my easy recommendations: Bias kit and the 'more bass' kit, and perhaps the Standby switch kit. All of these 'kits' can be read about and you can source and manage the parts shopping yourself, or you can order them from Bill, your call. I mentioned the trannys earlier. The OT not great sonically, made by Schumacher of Mexico these days, so maybe consider a swap. The best is MM but I've installed MCI iron, too, the DR and the 20 watt Marshall varieties are good, 6.6K-8K.

[M Fowler]

Here is a post where I show What I did to a customer's BJ after he was tired of paying for repairs

http://el34world.com/Forum/index.php?to ... #msg180756

https://tubeamparchive.com/viewtopic.php?t=25676

[The New Steve H]

Thanks for all the great info. I'm going to play it occasionally and see if I still want to change anything. Right now the only issue I notice is a limited ability to generate clean sounds. Not really my sound, so I'm not too bummed.

When I opened it up I was a little disappointed by the look of the transformers, but I didn't know people actually took the time to replace them.

I'm not a big fan of standby switches. I don't put them in my own amps.

Neat project M.