| Author |
Topic: Spring Reverb |
Jon Light (deceased)
From:
Saugerties, NY
|
Posted 23 Mar 2006 12:37 pm |
|
Just curious---anybody ever physically mess with a reverb tank to try to mute an overly long dwell? Yes, I know there are other tanks and I know they are pretty cheap. But I wondered if something stuck onto one or two springs--I dunno, rubber band, twist tie, bacon strips--could change the sensitivity or the decay without trashing the whole thing.
I'm just tired and hungover from a late gig. I need something to stop my mind from wanderin'.....where it will go........ |
|
|
 |
Ray Minich
From:
Bradford, Pa. Frozen Tundra
|
Posted 23 Mar 2006 1:37 pm
|
|
What the heck does an "overly long dwell" sound like? This is interesting...
Too bad there ain't a wet/dry control like on the DeltaFex II. |
|
|
|
Donny Hinson
From:
Glen Burnie, Md. U.S.A.
|
Posted 23 Mar 2006 2:31 pm
|
|
John, they only cost about $20, and it really wouldn't be worth messing with (for me, anyway). However, if you wanted...you oould reduce the echo by adding a little fiberglass near the spring-ends...if you wanted.  |
|
|
|
Mark Herrick
From:
Bakersfield, CA
|
Posted 23 Mar 2006 3:31 pm
|
|
Maybe bubble gum...
------------------
|
|
|
|
Mike Fried
From:
Nashville, TN, USA
|
Posted 23 Mar 2006 3:51 pm
|
|
| You could try replacing the reverb driver tube (12AT7 if it's a vintage-style Fender) with a lower-gain substitute such as a 12AU7. This reduces the drive signal to the tank, which reduces the dwell to some degree. |
|
|
|
Bob Metzger
From:
Waltham (Boston), MA, USA
|
Posted 24 Mar 2006 9:03 am
|
|
Hi Jon,
You should be fixing a hole!
Bob M. |
|
|
|
Steve Waltz
From:
USA
|
Posted 24 Mar 2006 10:22 am
|
|
I just ordered an new accutronics reverb tank with the three spring set up with long decay. They are around $25 from antique electronincs and they just plug in. You can get them with shorter or longer decays. I've heard they are a good change if you don't like your reverb. I have a Dave Funk book that talks about reverb mods to fenders. One suggestion he had is to replace a resistor in the reverb circuit with a variable resistor which is a pot that can decrease the signal of the reverb in a way similar to a dwell control on the stand alone units. I'm thinking of trying this but I want to find a good place to mount it without altering the chassis. I've heard that the ground switch on these amps is not needed anymore after the amps have been changed to a three prong chord. That switch spot could be a good place for a new pot to control the reverb.
Has anyone done this?
Steve[This message was edited by Steve Walz on 24 March 2006 at 10:24 AM.] |
|
|
|
Jon Light (deceased)
From:
Saugerties, NY
|
Posted 24 Mar 2006 10:35 am
|
|
Bob---Hah! 
I'd be curious about that dwell mod, Steve. If you can provide any links or details I'd be interested. I've never known how the dwell control works on multi knob reverb controls.
But it would be useless for what set me off---the reverb on the Steel King is WAY too deep and long for my tastes. not a matter of wet/dry. It just goes on and on---if I use more than just a hair it becomes a mud chamber.
BTW--another good place on a Fender tube amp for adding a pot is the ext. speaker jack, assuming you don't use it. I put a mid control there on my SFDR.
|
|
|
|
Steve Waltz
From:
USA
|
Posted 24 Mar 2006 10:54 am
|
|
"BTW--another good place on a Fender tube amp for adding a pot is the ext. speaker jack, assuming you don't use it. I put a mid control there on my SFDR."
Great idea. Thanks for the suggestion.
Steve |
|
|
|
Steve Waltz
From:
USA
|
Posted 24 Mar 2006 11:28 am
|
|
From the fender forum:To tame reverb....
Replace the 100k linear pot with a 100k audio pot. Works like a charm and can dial in as much verb as you want without that big hump at 3 on the dial. I do this to all my amps for that same reasson.
Like Steve D said, change the 12AT7 reverb tube to a 12AU7 or a 6189 (Mil. spec) first. Probably will do the trick.
What Dwell essentially does is control the
L E N G T H of the reverberation signal or echo sound.
On Fender BF amps it is fixed and the "Reverb" control only controls how much "wet" signal is combined with the "Dry" signal before reentering the main signal path usually at the last stage or at the PI.
I just looked at the schematics for the Vibrolux Reverb.
There is a 1 meg resistor going to ground from the 12AT7 control grid. Remove it and replace it with a 1 meg POT, and you will be able to control the Dwell of your reverb. On my BFPR build I labeled the two controls as "Dwell" and "Mix".
|
|
|
|
Dave Grafe
From:
Hudson River Valley NY
|
Posted 24 Mar 2006 2:58 pm
|
|
I believe that what Fender calls "dwell" is associated with the signal level of the spring's driver input. Other devices may label this "drive" or something else.
The sound of and individual spring reverb - including the decay time - is a function of the mechanical properties of the tank, changing these properties by adding (or removing?) bits of matter will certainly change the sound but not necessarily the length of the decay at a given level.
If what you want to do is to fool with it and learn yourself some about it then go on ahead, sounds like fun to me. On the other hand, Jon, if you just want a great sound with no hassles the GO HERE >>> http://www.accutronicsreverb.com/
You can get exactly what you want in a matter of a very few days for probably under thirty dollars shipping and all. You might even be able to sell your old one to another forum member. |
|
|
|
Dave Grafe
From:
Hudson River Valley NY
|
Posted 24 Mar 2006 3:05 pm
|
|
...that is of course if the spring itself is the actual problem,
| Quote: |
| It just goes on and on---if I use more than just a hair it becomes a mud chamber. |
it sounds like maybe the input control is way too hot, the suggestion about swapping out a linear pot for a log one might be a better move. I would have to see the schematic to say much more and have it mean anything...too bad Fender doesn't have a Mike Brown here to open up a vein now and then for us.... |
|
|
|
Steve Waltz
From:
USA
|
Posted 26 Apr 2006 12:10 pm
|
|
I know this topic is a bit old but.......
I ordered a new accutronics tank with three springs and the long decay. The sound of the reverb is much better but the decay is a little long for me. I put in a 12AU7 which has a lot less gain than the 12AT7. There was a big difference in sound and the reverb conrol is less touchy. I used to only be able to get what I wanted befor 3 on the dial now there is more wiggle room and it is around 5. The decay is better but still a bit much. I have heard that with new tanks you can tame this problem by stretching the springs! Basically you are adding years of play and travel time onto them. People say it works. I'll try it and let you know.
Steve |
|
|
|
Colby Tipton
From:
Crosby, Texas, USA
|
Posted 26 Apr 2006 1:22 pm
|
|
I ain't even going to get into this one. nob on the control panel on the amp, but I will stay out of this one for control over your reverb.
|
|
|
|
Jon Light (deceased)
From:
Saugerties, NY
|
Posted 27 Apr 2006 1:17 pm
|
|
| Steve--I'm most interested in your follow-ups on this. If chewing gum ends up being the magic ingredient, be sure to include the brand & flavor. |
|
|
|
Steve Waltz
From:
USA
|
Posted 27 Apr 2006 1:56 pm
|
|
What does this mean?
"I ain't even going to get into this one. nob on the control panel on the amp, but I will stay out of this one for control over your reverb." |
|
|
|
Dave Grafe
From:
Hudson River Valley NY
|
Posted 29 Apr 2006 9:48 am
|
|
| Steve, that is the same tank that I have in my Randall. I like the decay of the low frequencies but have to cut the highs quite a bit to get it so behave to my satisfaction - my amp has reverb tone controls, I have the lows at about 8 and the highs at about 3 or a bit less. Rather than tamperiong with the springs - which are pretty delicate - a simple cap can provide a low-pass filter in your amp's reverb circuit, if you match it with a pot you can have variable tone control of the 'verb. |
|
|
|
