Reverb idea....... new????

[makepeace]

@txstrat: unless you want the original Hammond schematic, he already posted his schem--scroll up!!

i'm a little confused.. the schematics he posted don't include the reverb stages, but they do show the connection points.

[txstrat]

@txstrat: unless you want the original Hammond schematic, he already posted his schem--scroll up!!

Yep, I'm interested in the hammond schematic.

[J M Fahey]

Yep, I'm interested in the hammond schematic.

Me too.
I had thought it was the original Fender one, 12AT7 transformer driving the tank, etc; but since it seems not to be the case ... please post what you actually used.
Thanks.
PS: as far as I can see it, the "strong reverb" noticed probably comes from the fact that it's always driven full tilt, from the strong signal present before the tone stack, and is not affected by the volume control, leading to the peculiar situation where you can have a strong delayed signal ... *without* a "dry" one.
Just set your Volume on "0" and Reverb on any value.
Talk about deep reverb !!
This exaggerated reverb response will be most noticeable at bedroom levels, evening out at stage levels.

[jpfamps]

I use Splan 6.0

I like the look of this.

Does the standard package include the valve (toob) symbols?

[riz]

i'm a little confused.. the schematics he posted don't include the reverb stages, but they do show the connection points.

DUH!! My bad!

[Bernardduur]

I like the look of this.

Does the standard package include the valve (toob) symbols?

Yes! Both triodes as pentodes as diode / rectifiers.......

[Bernardduur]

Reverb:


PSU:


Orignal Hammond schematic

[J M Fahey]

Hi bernadduur, thanks for posting.
I don't understand how a single 12AT7 triode, loaded with 100K, can drive *any* hammond tank, even the highest impedance one, to any significative level.
Maybe that's why you had almost no reverb at all with the original implementation.
I also can't understand how the "original Hammond schematic" version you show can drive any reverb at all, since the plates are AC grounded thanks to C18.
A 100uH coil in series will not change that.
A schematic I found, shows a proper transformer coupled tank driver:

although I don't know how heavily modified is it.
Good luck.

[Chuck H]

+1
The triode arrangement your using to drive the tank is typically used for voltage gain, not drive current. Ampeg used a lot of capacitor coupled reverbs and Merlin has some GREAT alternative drivers on his site. Even if you are getting satisfactory reverb levels it's generally reported that reverb tanks sound much better when driven harder. I think a rework could result in improved tone and performance.

[Bernardduur]

I know this circuit won't work that well for reverbs but I got the Hammond amp in a few years ago, traced it and was kind of pleased with the reverb levels....... strangely yes!

So I just took the values and the tank (as it was free) and tried it and was dazzled by the fact it worked like a charm..... with the dwell at full I get a really nice reverb wash (long) and enough to alter........ dunno why but it works for me......

Must say that I want to alter it to a more typical reverb section; for now, I am just satisfied

[txstrat]

Must say that I want to alter it to a more typical reverb section; for now, I am just satisfied

It might be worth trying to alter the point from where to feed the reverb - maybe after the volume control, or even after the second stage.

[Bernardduur]

Yes! I will look into that! After the second stage you'll get the same idea as before so that is no go..... after the volume pot is sure a way BUT I kinda like the 100% wet reverb I can get

[txstrat]

I kinda like the 100% wet reverb I can get

Yeah, that's kinda tempting. I'm thinking about to try that too.

[Bernardduur]

Yeah, that's kinda tempting. I'm thinking about to try that too.

It is awesome for reverb freaks (like me)

[AmpRX]

I bought sPlan 7.0. Very happy with it. Thanks for the recommendation!