Heathkit Mystery find - GD-61 Reverb unit
- Thread starter birddog
- Start date
mhardy6647
Lunatic Member
Birddog's reverb thingy in all its glory. The amp is working fine after a little freshening up. The reverb tank, though seems to add quite a bit of hum to the loop. Dunno why -- I have no insight into the guts of these things, except that there's a spring/springs inside.
Still thought folks'd like to see a few photos.
(that's a 'before' photo of the underside)
Still thought folks'd like to see a few photos.
(that's a 'before' photo of the underside)
chosenfool
New Member
hi, all,
lurker/rookie out of the shadows here, chiming in on this. i scored one of these things recently - it looks the same as what's pictured (only dustier), so im not gonna clog y'all with more of the same.
at first i didnt know how to use it, but i remembered my Kalamazoo Reverb 12 - there are leads that hook up DIRECTLY to the speaker that enable the reverb (other than the OT's). On this one, i fashioned a makeshift connection out of 2 leads with alligator clips on one end, hooking each up to the - and + of my main amp's speaker, coming from the reverb amp's screw-in connections.
i have to say, it works VERY WELL with my guitar-amp setup. Surprisingly I didnt notice any hum (though it has a hum pot) - from what ive seen and heard, add-ons such as these usually induce hum, caused by a ground loop(?).
some questions/opinions needed:
1) can this be integrated in another main tube amp, using only 1 speaker for both the main amp and this? its like 2 amps driving 1 speaker. Thing is, if i try this the tube reverb amp looks like its looping into itself (inputting into its own output). sounds dangerous for the amps...
2) if #1 is a NO, can this tube reverb amp be made into a standalone amp? Just needs a direct input to plug an instrument into - it seems to be complete for a stand alone unit (PT, OT, preamp and power tubes). Maybe fashion its own volume (and /or tone) control. The overall volume is dependent on the main amp. The switch and amount of reverb is controlled on the front knob, and the knob on the back is for adjusting levels between left and right channels.
3) maybe make it smaller, a bit more portable/manageable - it is BIG. with the back with so many round holes, im not sure if the cabinet has any effect at all on its sound...
4) if no to #s 1 and 2, maybe an easier way to hook up to other existing amps? Though it seems alligator-clipping to the main amp's speaker is the only easy way to do this on most older combo amps. on a head its easy (and some newer combos with 1/4" output connections going to the internal speaker) -use a mono 1/4" phone adapter (2in/1out). The male end connects to the main amp's speaker outs, one goues out to the speaker cab, one connects to the tube reverb amp. I will try this later (also will try to see if an external speaker out alone on a combo will work, though i doubt it. it seems it needs a main speaker first before it can work. it may work on combos whose external speaker output does not cut off the internal speaker... i will try this also).
one mod im already thinking of doing - make separate controls for the left and right channels. Also make it safer with a 3 prong plug,maybe a separate on/off switch.
admittedly it is cumbersome, especially when you can have a cheap $30 reverb pedal that can do more. But i like that true/natural spring reverb sound, and the way this thing initially sounded for me (quiet and deep-sounding!), its a keeper. Just prefer it with more ease of use. what do you guys think?
lurker/rookie out of the shadows here, chiming in on this. i scored one of these things recently - it looks the same as what's pictured (only dustier), so im not gonna clog y'all with more of the same.
at first i didnt know how to use it, but i remembered my Kalamazoo Reverb 12 - there are leads that hook up DIRECTLY to the speaker that enable the reverb (other than the OT's). On this one, i fashioned a makeshift connection out of 2 leads with alligator clips on one end, hooking each up to the - and + of my main amp's speaker, coming from the reverb amp's screw-in connections.
i have to say, it works VERY WELL with my guitar-amp setup. Surprisingly I didnt notice any hum (though it has a hum pot) - from what ive seen and heard, add-ons such as these usually induce hum, caused by a ground loop(?).
some questions/opinions needed:
1) can this be integrated in another main tube amp, using only 1 speaker for both the main amp and this? its like 2 amps driving 1 speaker. Thing is, if i try this the tube reverb amp looks like its looping into itself (inputting into its own output). sounds dangerous for the amps...
2) if #1 is a NO, can this tube reverb amp be made into a standalone amp? Just needs a direct input to plug an instrument into - it seems to be complete for a stand alone unit (PT, OT, preamp and power tubes). Maybe fashion its own volume (and /or tone) control. The overall volume is dependent on the main amp. The switch and amount of reverb is controlled on the front knob, and the knob on the back is for adjusting levels between left and right channels.
3) maybe make it smaller, a bit more portable/manageable - it is BIG. with the back with so many round holes, im not sure if the cabinet has any effect at all on its sound...
4) if no to #s 1 and 2, maybe an easier way to hook up to other existing amps? Though it seems alligator-clipping to the main amp's speaker is the only easy way to do this on most older combo amps. on a head its easy (and some newer combos with 1/4" output connections going to the internal speaker) -use a mono 1/4" phone adapter (2in/1out). The male end connects to the main amp's speaker outs, one goues out to the speaker cab, one connects to the tube reverb amp. I will try this later (also will try to see if an external speaker out alone on a combo will work, though i doubt it. it seems it needs a main speaker first before it can work. it may work on combos whose external speaker output does not cut off the internal speaker... i will try this also).
one mod im already thinking of doing - make separate controls for the left and right channels. Also make it safer with a 3 prong plug,maybe a separate on/off switch.
admittedly it is cumbersome, especially when you can have a cheap $30 reverb pedal that can do more. But i like that true/natural spring reverb sound, and the way this thing initially sounded for me (quiet and deep-sounding!), its a keeper. Just prefer it with more ease of use. what do you guys think?