DIY Spring Reverb - Alembic Stratoblaster to Drive it? [Archive]

capth00k

July 21st, 2012, 11:21 AM

Hey guys,

I have an old Fender Spring reverb unit laying around, and i've been scowering the web for details on how to drive it. Turns out you need an amplification circuit on both input, and output. My question is -- would the Alembic stratoblaster circuit suffice? It's a clean, transistor based boost. Most of the schematics i've seen use the LM741 op amp run at 4.5 volts, so i'm just wondering. Thanks!

soundguruman

July 21st, 2012, 01:48 PM

It's a heavy load that is driven by a small tube output transformer. I'm not sure that 741 has enough current to drive it.
Depending on the number (stamped on the tank) of the reverb tank, you will have different input and output impedance, and there are several types available...and so it's hard to say what will drive it until you first "decode" the part number, or measure the in / out.
For example 4AB3C1B is 8 ohm in, 2250 ohm out (see charts)
http://roymal.tripod.com/accutron.htm
It usually takes quite a bit of drive voltage. This is electrical to mechanical, through the springs, and then mechanical to electrical.


	Telecaster Guitar Forum > The DIY Channel > Burnt Fingers DIY Effects > DIY Spring Reverb - Alembic Stratoblaster to Drive it? PDA DIY Spring Reverb - Alembic Stratoblaster to Drive it? capth00k July 21st, 2012, 11:21 AM Hey guys, I have an old Fender Spring reverb unit laying around, and i've been scowering the web for details on how to drive it. Turns out you need an amplification circuit on both input, and output. My question is -- would the Alembic stratoblaster circuit suffice? It's a clean, transistor based boost. Most of the schematics i've seen use the LM741 op amp run at 4.5 volts, so i'm just wondering. Thanks! soundguruman July 21st, 2012, 01:48 PM It's a heavy load that is driven by a small tube output transformer. I'm not sure that 741 has enough current to drive it. Depending on the number (stamped on the tank) of the reverb tank, you will have different input and output impedance, and there are several types available...and so it's hard to say what will drive it until you first "decode" the part number, or measure the in / out. For example 4AB3C1B is 8 ohm in, 2250 ohm out (see charts) http://roymal.tripod.com/accutron.htm It usually takes quite a bit of drive voltage. This is electrical to mechanical, through the springs, and then mechanical to electrical.