Brown Concert Volume/Tone Controls

[JMT]

I've previously read a post on this forum about the way the volume controls interact on a Brown Concert. I even printed it off. Unfortunately, now I can't find the info. I use the Concert for harp and I'm going to do some experimenting with it. If I recall the author suggested diming the volume control on the tremelo channel to tighten up the first channel. Seems that there were suggestion for the tone controls, too.
Thanks in advance,
Jay

[Chuck H]

I don't see any reason why the volume controls on any of the Concert amps should be interactive. At least not in a significant way. There are pre blackface Fender amps that have interactive volume controls though. This could be a generalization that doesn't apply to the Concert.

As for tone settings, I can tell you exactly what to do. Turn the knobs until it sounds good

Chuck

[MWJB]

There is a degree of interactivity even on the BF Fender controls, the treble control (of the channel you are not using) has the biggest impact & Vol & bass need to be full up.

Jay, set the bass on the channel you are using (assuming Normal) to the point, just before the 2 draw bends (A or G harp) begin to mush out, then wind up Vol & Bass on the vibrato channel to full. Now start dialling in the treble control on the vibrato channel, it acts like a bright/cut control, I usually end up around 6-7. Set this before setting the normal channel treble control (0-4). It gives a tighter, punchier sound than just using the Normal channel controls...some may find it too aggressive.

Presence will normally be from 3 o'clock to fully up.

It's also worth noting that many players pull tubes V2-V5 (or V4 if it is a 6G12, 5 preamp tube model) to rebias V1 for a hotter, tweedier style tone. So you have some options.

[JMT]

Thanks

This is exactly what I was looking for and I'm pretty sure that MWJB was the original poster. I suspect this may be why the amp sometimes sounds better than others....by accident! Thanks again!
Jay

[Bruce / Mission Amps]

This is exactly what I was looking for and I'm pretty sure that MWJB was the original poster. I suspect this may be why the amp sometimes sounds better than others....by accident! Thanks again!
Jay

The fact that it used trannys from a tweed Bassman don't hurt either.

[pdf64]

What's the cause of the interactivity of channels in a BF Fender? The only place I can think of where the channels might couple together (apart from the general interwire capacitance) is at the shared cathode of the 2 1st stages, due to the (shared) bypass cap haing some series resistance / inductance.
Is the interaction reduced if the cathodes are split?

[MWJB]

Bruce wrote: "The fact that it used trannys from a tweed Bassman don't hurt either." Only earlier Concerts, (<'61?) used the tweed bassman OT. Later '62/63 used Schumacker OTs, some with the same part no as the tweed bassman, later ones not (same designation as Super Reverb). PTs were the same as Brown Twins 67233 (also Pro/Bandmaster/Vibrasonic), to start with, then later could be 125P7D/P7A.

Brown Supers used the same PT as the Bassman.

PDF64 wrote: "Is the interaction reduced if the cathodes are split?" No.

[Chuck H]

pdf64 also wrote;

What's the cause of the interactivity of channels in a BF Fender?

+1

I don't get it either. I'd like to know though. Otherwise I'm likely to keep giving misinformation as above.

Chuck

[MWJB]

What's to know? Turn on a BF Fender, play through it & see...it does what it does, whether you can see why, or not.

[Chuck H]

Easy enough for the guys with a BF, BF type build (complete w/both channels!) or brown Concert around. All my amps are builds anymore. As a consequence they're all single channel.

Oh well, I'll just have to remember to check it out next chance I get. I'm not doubting it's true (so you don't have to pop a vien) I just think it's better to understand something than to simply know it. That's where I was coming from.



Chuck

[MWJB]

If I was sure as to the why/how, I wouldn't be keeping it secret. :-)

[JoeM]

Interesting. I'll have to try that too. I've owned a Super Reverb for a long time, but just out of habit always kept the tone and volume on the 'Normal' channel all the way down.

[MWJB]

A lot of folks do, due to the increased hiss from having the other channels controls fully up.

[JMT]

PT

Mine has an NOS BFSR power tranny. OT is probably original.

[Bruce / Mission Amps]

6G12

I had a friend bring his dead stock 6G12 over for this test (well it has been recapped and has new tubes) and between three of us... with respect to the unused channel's tone controls effecting the output tone.... none of us could hear any of the effects everyone is talking about. Rats
I'm not sure what the others are hearing... and like some others, if it does do it, I can't figure out why it would do that anyhow... there is a kazillion ohms impedance between the tone control sections and the two mixing resistors.

Also, I don't think I've ever seen a bf or sf Pro or Bandmaster with anything other then a small channel mounted, 25-30 watt OT.
The old Concerts used big honkin' iron... I always thought from Triad in those days.
And it is Schumacher (later called Woodward Schumacher).