Recent Posts

Pages: 1 2 3 [4] 5 6 7 ... 10
Classified / Coliseum 300 with two 215SH cabs
« Last post by claytoy on October 25, 2017, 08:03:17 am »
In Costa Mesa CA 92626 - speakers stock sq mag recently re coned -- check out pics. 1000$   Clay 714 380 2417
Q & A / Re: Sunn 215B buzz/rattle.
« Last post by Isaac on October 25, 2017, 07:10:17 am »
Before giving up, I'd rotate the driver. It could be cone sag. When reinstalling, make sure the hardware is snug, but not overtight. Overtightening can warp the frame, causing this exact symptom.
Q & A / Re: Concert Bass Mid control not working
« Last post by _peter on October 25, 2017, 04:03:26 am »

according to this schematic:
the bass pot isn't stacked on the mids pot as in the usual fender/marshall tonestacks.
With bass at zero, the signal at the mids pot is shorted to ground. Therefor the mids pot can't work in this situation.

Q & A / Re: Sunn 215B buzz/rattle.
« Last post by _peter on October 25, 2017, 02:14:58 am »

there either seems to be an object between the coil and the magnet or the coil isn't centered anymore.
In both cases there's nothing you can do about it but recone or swap the speaker.


Q & A / Concert Bass Mid control not working
« Last post by Hd0521 on October 24, 2017, 09:40:32 pm »
With the mids dimed and the bass and treble at zero there is a very low volume tone coming through. If I back the mids down to zero the volume of that tone doesnít change. If I dime either bass or treble the volume increases. Iím assuming itís a passive Eq stack. I opened the amp up and it looks like the original pots wired right to the board. Any solution before having the pot replaced?
Q & A / Sunn 215B buzz/rattle.
« Last post by Hd0521 on October 24, 2017, 09:30:31 pm »
Brought home a concert bass Head and 215B cab today. Thereís a buzz (similar to a fuzz effect) from the top speaker only when I play. If I lightly place my hand on the lower part of the speaker cone it goes away. If I light place my hand on the upper part of the cone itís more dramatic. Any ideas? Thanks in advance.
Q & A / Re: Footswitch
« Last post by Watson on October 24, 2017, 08:37:36 am »
Here are a few shots of the beta foot switch circuit board in a unit I have.

Q & A / Re: Footswitch
« Last post by loudthud on October 23, 2017, 08:44:59 pm »
Sorry, I don't have anything to contribute on the Beta footswitches. These are pretty rare and at least one company was making a clone for use by people needing one for their Beta amps. I know in the early years Sunn used an aluminum extrusion with a U shaped sheet metal bottom-side plate. In later years they might have run out of the extrusion and not reordered because there is usually a 500 or 1000 pound minimum order.

It would be nice if you could snap a clear picture of the inside of the footswitch and post it here. TIA!
Q & A / Re: Footswitch
« Last post by YandT on October 23, 2017, 02:03:00 pm »
Thanks for the reply.

So, you're pretty confident that this is a Beta Switch III?  What is the more common silver, aluminum model referred to?

I know this footswitch works for the Beta Lead I have, but I was more curious as to whether or not it was designed for the Beta Lead or something else.  Because it doesn't look like the silver, aluminum footswitches more common to the Betas.  That's why I thought that maybe it was made for the PL-20.  But, the silkscreening is different than the other one pictured in the link I provided.  That is another reason I thought it might be a prototype model.

Besides the picture of the one in the link, and the picture that was in the E-bay listing from which I bought this one, I haven't found a picture of another one in existence.  Is this that rare?

Thanks for any information you can provide.


Q & A / Re: Footswitch
« Last post by loudthud on October 22, 2017, 08:37:21 pm »
A Beta Switch III footswitch should work on any amp (or preamp) that has the same connector on the amp end. There is a Beta Switch II which just doesn't have the Reverb kill switch, but it uses the same connector. It will switch channels but can't control the Reverb. There are some Coliseum Lead (very rare) footswitches that have different connectors.
Pages: 1 2 3 [4] 5 6 7 ... 10