Sensitivity to Echo?

[Sowhat]

I use a single speaker cabinet with a 100 watt solid state head and a 100 watt tube head through a head switcher. This gives me a wide range of tonality for sure but I also have a nasty habit of using a signal processor on the front end. I set this processor for some overdrive, and just a touch of compression and hall echo... not too much, just a tad. This makes the solid state head sound fantastic but when I switch to the tube head the hall echo just overwhelms the sound. The Solid State head is a Elliott Sound Products P27 and the tube head is a Marshall JCM800-2203. I imagine there's something about the tube preamp versus the opamp preamps that is causing this. I was just throwing this out there to see if anyone has some theories as to what's up with this.

[pdf64]

My guess is that the Marshall preamp is being overdriven.
Use the low gain input and and turn the master up full.
Unfortunately the massive bright cap across the preamp volume control may cause the tone to go trebly.
If that's the case, consider removing the cap or perhaps a 12AY7 or 12AU7 in V1 may allow the control to be turned up enough to lessen the effect of the bright cap.

Have you got the bright switch activated on the ESP P27?
Did you build the P27 yourself? Would you recommend it?

[Jazz P Bass]

Just a thought but shouldn't the reverb be in the fx loop?

[d95err]

The comptession caused by overdriving the amp will amplify delay and reverb. It doesn't matter if it's tube or solid state (try putting a dist pedal after the delay/reverb...).
To use delay before an overdriven amp/pedal, set feedback to zero and the time fairly short (like the early Van Halen recordings).

[J M Fahey]

Agree and add:
the tube amp will compress somewhat, say 10 dB, before actually hard clipping.
Within that compression range, the so called "sweet spot" in Tube amps, compression will even out loud and soft sounds, so effects, which usually are softer than the main dry sound, will by comparison sound louder then expected.

Once you get into the hard clipping area, plain distortion muddies the time based effects, reverb and delay.

Standard SS amps do not have thet intermediate area, they are either clean as a whistle or squarewave buzzing.

[Sowhat]

Have you got the bright switch activated on the ESP P27?
Did you build the P27 yourself? Would you recommend it?

Yeah the brite is on. Yeah, I built it myself and it's a really nice amp, have used it trouble free for about 3 years now and it was a joy to build. I built the JCM800-2203 as well which was another fun build, I built the isolation speaker cabinet too... Seems that I built the whole rig except for the head switcher which is a Radial TS Headbone and the effects processor which is a DeltaLabs DGFX1.

[Sowhat]

Thanks for the opinions... they have a lot of merit and insight. I have this notion that I want to use the head switcher to simulate lead and rhythm channels just as if I had a multi channel head. It works pretty good in theory and practice, especially with the solid state heads inherent tightness and the tube heads crunchiness. The effects processor at the front end is probably not the best spot for it but it's kind of hard to put the one effects processor in between the two preamp/amp pairs. All in all this is not a loosing proposition by any means, I have used this rig to record an LP so far and it sounds awesome, even with this blooming echo on the tube side of things. Funny, It's not as pronounced when recorded through the internal SM57 mic into the AI/DAW but it becomes more noticeable when I open up the iso cab and play at concert volumes... still sounds great, but a little echo-ey.

[Sowhat]

Just so you know what I'm working with, here's a little snapshot of my rig...

[Chuck H]

The approach of running effects into the input of a clean amp AND into the input of a dirty amp is terribly flawed. Distortion and clipping, as they apply to guitar tone, are signal processing effects that should always be placed first in the processing chain. Never last, which is how you're doing it. I'm not saying there are no good tones to be had this way, but it's fraught with problems that limit versatility greatly. One exception might be the use of a wha or EQ in front of the distortion to "shape" it. But generally you do most effects and the advantages of a clipped signal a lot of damage by feeding your processed signal in to the distortion rather than feeding your distortion into the processing. You would get MUCH better results finding a distortion pedal you like, putting it in front of the rest of your signal processing and just use the solid state amp.

[gui_tarzan]

I thought that would be the other way around, it seems like sending a distorted signal through other effects would drastically change the other effects for the worse. I'll have to try that the next time I have a chance to play guitar (instead of bass).

[Chuck H]

I thought that would be the other way around, it seems like sending a distorted signal through other effects would drastically change the other effects for the worse.

Nope. Think about this, if you run a reverb into a distortion you get a distorted reverb. If you run distortion into reverb you get reverbed distortion. This is only one example.

[uneumann]

Nope. Think about this, if you run a reverb into a distortion you get a distorted reverb. If you run distortion into reverb you get reverbed distortion. This is only one example.

Forgive wandering off-thread a bit... but I've played with varied sequences and paths. A distortion first and reverb after is common, but the final signal often distorts again in the PI and output stage. In most situations, distortions happen in multiple places and effects are just somewhere in the middle.

I happen to like running parallel paths - a clean signals into reverb and mixing that output with a separate distorted signal (post reverb mix). The parallel path approach is also used in the GSP1101 modeling preamp. It sounds better (to my ear) than the distort before effects option. Since the GSP offers both, A/B comparisons are easy. Of course its a DSP system, so who knows what side effects are also in there.

All I'm saying is that a simple rule - first A then B - doesn't really hold up very well.
It may be a good reference point, but anything goes if it sounds good.
I've also run the GSP as an effects (reverb etc) unit before a combo - and then let the combo preamp distort. Its not hard to make that also sound good.

[J M Fahey]

Just so you know what I'm working with, here's a little snapshot of my rig...

[ATTACH=CONFIG]30725[/ATTACH]

Hey !!!!
Killer setup!!!
Very nice !!!
Congratulations