Running two amps

Robbie Bossert · Post by **Robbie Bossert** » 10 Sep 2018 10:56 am

Just curious. When running two amps, do you generally run one with all your FX and one completely clean and fairly dry? Any suggestions?

Robbie Bossert

Donny Hinson · Post by **Donny Hinson** » 10 Sep 2018 12:32 pm

I'd only run one "dry" only if it's primarily used as a band monitor. If both were for the audience, I'd use EFX on both.

Robbie Bossert · Post by **Robbie Bossert** » 10 Sep 2018 2:12 pm

Thanks Donnie. I just tried it with FX going to one and Dry to the other. To my ear it sounds pretty mid rangey, or honky, I'll try FX in both..

Robbie

Drew Pierce · Post by **Drew Pierce** » 10 Sep 2018 3:10 pm

Why do you feel the need to use two amps? IMHO, if you're not getting the sound you want out of your amp, try a different amp.

Jim Sliff · Post by **Jim Sliff** » 10 Sep 2018 4:42 pm

What Drew said. OR add an extension speaker cabinet of the correct impedance. The added square inches of speaker cone improves dispersion and "fills out" the sound. It's very rare that two amps are needed unless you specifically want to run in stereo or prefer the sound of lower-output amps cranked up, in which case you probably ned at least two amps to cover various venue sizes/configurations.

Two amps have to be checked for speaker polarity and proper AC wiring polarity as well. Speaker polarity issues are when one cone (or set of cones) moves forwards and the other set are reversed, not only because o speaker wiring but sometimes use (vs not using) effect loops can reverse the polarity. random, unexplained volume dropouts or thin tone can occur.

AC wiring issues usually occur in amps that have been serviced and power cords rewired or replaced. There's a specific way to wire hot and neutral wires, and if they are not both correct ground issues and shock danger can be present.

Accordingly, I don't recommend a dual amp setup unless somebody qualified has checked it all out and it's absolutely necessary.

Rich Upright · Post by **Rich Upright** » 10 Sep 2018 5:25 pm

I always run 2 amps with a DD-3 stereo delay. I send the dry signal (with reverb) to 1 amp, and ONLY the delay note to the other amp (which can be a smaller practice amp). It gives you a very big "wall of sound" sound, where you can hear the delay without it being overpowering. Can't do it on gigs where the steel is mic'ed through the PA, obviously.

Jerry Overstreet · Post by **Jerry Overstreet** » 10 Sep 2018 5:43 pm

When we started doing this back in the '80's the thinking was to keep one amp pure with just some reverb and put all the other effects in the second amp. Mixing the volume of the two amps gave us a stereo effect, or the presence of two different sounds at least. I did this for several years until I began using rack rigs and satellite speakers.

The only problem I know of is the ground loop hum you get from wiring two amps together in this way. You need to find a way to lift one of the amp grounds or find a hum eliminator device that's made for that purpose. Many of us did this for several years without any other problems save the hum issue...at least of the people I know and know of including many of the Nashville pros and other pro players around the country.

Pete Burak · Post by **Pete Burak** » 10 Sep 2018 6:49 pm

I run a Stereo rig anytime room on stage allows.
I like the lush surround sound.
I run the effects equaly to both sides.

I have heard running one speaker dry is fine too, I defer to others on that setup.

ajm · Post by **ajm** » 11 Sep 2018 1:24 pm

There are those that run a single amp.
Those that run two amps in either wet-dry or wet wet.
Then there are those that run three amps wet-dry-wet.

Run what makes you happy and works.

Rich Upright wrote: "Can't do it on gigs where the steel is mic'ed through the PA, obviously."
Why not?
If you had a separate mic on each cabinet, and had the sound man who understands the principle pan/mix them properly......

Donny Hinson · Post by **Donny Hinson** » 11 Sep 2018 5:33 pm

Robbie Bossert wrote:Thanks Donnie. I just tried it with FX going to one and Dry to the other. To my ear it sounds pretty mid rangey, or honky, I'll try FX in both.

Rob, that tone problem might be a speaker phase issue. Try temporarily reversing the speaker wires on one of the amps, and see if that sounds any better!

Jim Sliff · Post by **Jim Sliff** » 11 Sep 2018 7:41 pm

Regarding ground loop hum - that does not occur in most circumstances. If it's suspected and lifting the ground on ONE amp quiets the hum great - but only as a temporary solution.

Because if it does happen it indicates a wiring problem in one amp, one AC source or outboard gear connected to only one of them. Permanently using a ground lift as a solution is not a safe way to "solve" the problem - all it does it relieve a symptom and the problem still needs to be dealth with

Olli Haavisto · Post by **Olli Haavisto** » 12 Sep 2018 9:14 am

The solution for ground loop and phase problems that may occur with a two amp set up safely:
https://lehle.com/EN/Lehle-P-Split-II

ajm · Post by **ajm** » 12 Sep 2018 10:27 am

What Jim Sliff said about ground loops. ^^

Don't play games with grounds and AC voltages and humming.
This is probably a good topic for another separate article on its own.

Olli Haavisto · Post by **Olli Haavisto** » 12 Sep 2018 10:33 am

True. With the Lehle I mentioned you can lift grounds safely at the input, not AC.
Highly recommended!