Pedals in effects loops

[owenmatt]

I have a demeter tga 2.1 amp and it sounds awesome but like a lot of amps the loop is line level and I have pedals and am loosing tone when I use the loop. The amps loop is tube buffered with send and return controls. I also have an ebtech line level shifter which makes it perfect for not overdriving my pedals and it brings the delays up to a better mix, but even with the ebtech I still get the tone loss. Im researching and a lot of people have this problem and say its an impedance issue. Im not completely familiar with impedances and how different impedances interact. Is there something more i can try? The pedals in my loop are as follows: efx send to ebtech line level shifter +4 -line level shifter-10 into isp decimater g string ii - strymon mobius - strymon timeline - strymon blue sky - wampler decible + for solo boost - back to line level shifter -10 - line level shifter +4 back to effecst return on amp. Seems runnung the send control higher than the return control sounds a little better, but i still loose the great sound of the amp with nothing in the loop. I really like my pedals and dont want to change them and i eliminated the pedals as being tone suckers by plugging the efx send directly to the efx return with and without the line level shifter with real short cables. Still get tone loss when doing it that way.

[WRGKMC]

I'm not familiar with your pedals, But all of my amps will run any pedals in the effects loop without any issues. I have no problems with impedance matching any of them. The inputs to pedals are instrument level so if your amp is a line level send and return , then you may need to boost the input to the pedals up about 3~6db to get the line level up to instrument level. You shouldn't have to attenuate the pedals output if you have a pot on the amp to adjust that, but bringing it back down the 3~6db would again bring it back down to line level.

 

The key is whatever you boost the input up to get a good signal, bring the output down that same amount/

[owenmatt]

I see what you mean but line level is hotter than instrament level. Line level is +4 db instrament -10dbv

[DeepEnd]

Is there a reason you can't put your pedal(s) between the guitar and amp like God intended? Or is it a preference thing?

[owenmatt]

Reverbs and delays sound best for me in the loop especially when using the amp distortion. Volume boosts work best in the loop as well as in front of the amp boosts gain more than volume

[AJ6stringsting]

I have a mint condition old Digitech Rp-1 with an efx's loop, in it I have a Seymour Duncan Pickup Booster, a Hush Pedal, an MXR 10 band EQ and a BBE Stomp Sonic for a great clean solo boost. I have a Rp-12 being feed into it handling the distortion and some light modulation before going into the Rp-1

Always treat your effects loop like the main line going into the amp and you'll always have the perfect tone

[onelife]

You said something here...

 

I really like my pedals and dont want to change them and i eliminated the pedals as being tone suckers by plugging the efx send directly to the efx return with and without the line level shifter with real short cables. Still get tone loss when doing it that way.

 

...that I think is the key. It looks like the issue is with the amplifier.

 

How do you know the loop is line level? I tried to find a drawing for the amp but all I could find was the manual. It did not specify the loop level. Do you have the schematic?

 

Did you try swapping any tubes? Maybe the tube(s) that buffers the loop is bad and only in circuit when something is plugged in the loop.

 

[owenmatt]

I once talked to demeter before i got the amp and they said this loop is meant for professional equipment that runs at line level. I tried swapping all preamp tubes. It has new poweramp tubes. Didnt make a difference. Amp is biased correctly. I did email demeter again to ask more on what they thought. Still waiting a reply.

[onelife]

Have you had a chance to try something that would qualify as a piece of professional equipment that runs at line level to help determine if it is indeed just a mis-match?

 

[WRGKMC]

I see what you mean but line level is hotter than instrament level. Line level is +4 db instrament -10dbv

 

Right, Got that backwards. I was thinking about the Rack units I have in my marshal loop. The Alesis unit I have in there now tends to be noisier because its line level. The balance knob I have for the effects loop will adjust from completely dry to 100% effects so its pretty simple to get the right gain levels set on the effect unit so the wet and dry levels match.

 

I too think you may have an issue with the send levels on that amp. It would be stupid to make an amp that only accepts line levels because you know every guitarist is going to be using their stomp boxes in that loop. Line level only is possible but fairly rare. All a loop is, is an insert between the preamp and power amp. It should be a hot signal depending on how much preamp gain you have set. Many guitar boxes have gain levels too so compensating for a hot signal should be doable.

 

Like I said, I'm not familiar with your pedals. They may have drop down resistors to prevent the true bypass switches from popping when activated and maybe that's jacking with the signal level. It may be possible to mod the pedals to work in that loop better.

 

Oh, and Deep End, The reason you want the time based effects in the loop between the preamp and power amp is because you want all your gain and saturation to occur before those effects. Having distortion from an amp after an echo unit can sound downright awful. If you run your amp clean you're OK but if you want to use your amps gain channels and have those saturated notes "in the echo" the echo has to come after the saturation.

 

Think of a cranked amp in a big room and how good that sounds. The saturation from the speaker comes before the room reflection so you want the echo after the preamp, before the clean power amp. Some amps get a little power amp saturation but that's not the heavy clipping most modern preamps provide.

 

In a studio, you add echo to the mic that's recording the amp. This way you capture both the amp chain gain and the speaker coloration and transients for the most realistic room sounds. Playing out live you'd do that by adding echo on the mixer that's micing the guitar amp.

 

Many amp makers knew this back in the day so many of your amps had no effect loops and had no reverbs. Its only later when effects became inexpensive and musicians wanted to copy what they heard on albums when effects loops were either modded into amps or came stock with those plugs.

 

When you record however, you really don't want to use allot of effects. Most studios have vastly superior echo's and reverbs they can use, and using more then one tracking isn't a very good idea. If that reverb or echo sucks you're stuck with it. If you record dry, you can keep trying different units and settings till you find the ideal sound. Same thing live. If you have a good sound guy with good gear, running that echo on the PA can sound much better, The guitarist already has natural room reverbs and reflections he should be using to "work" for him, making the entire room into one huge three dimensional echo chamber. The only time you need it on a guitar amp level is when the room is super dry or you have no sound man to add those for you.

 

I was doing sound for a band a few months ago, and I guess the guitarist never had someone who knew how to mix those in mains properly. After the set he was all elated on how great it sounded. He was hearing a dry amp and echo's on his guitar from the monitors and the room itself. By the second set I got him to stop trying to be Mr. DJ adding all that stuff in with crappy foot pedals and I got it to sound even better. Guess he never had it professionally done before and was totally stoked. Now they want me to mix for them at all their gigs which isn't really what I want to do. It began as a favor and a little extra cash, but after a few gigs, I'd totally burned out hearing their music.

 

I'm not a big metal fan and sitting there having to listen to it intently for 4 sets in a bar full of drunken bikers that are half brain dead is really boring. Its not worth the money having to sit through that on a regular basis even though they are a very good band.

[owenmatt]

Thanks for all the help and info. I have found the issue. For one i had a couple real cheap cables in the loop and i swapped them with better cables which helped some. The main issue i found though, i forgot when i was listing my loop pedals to include a boss ge7 eq pedal. I started over bypassing pedals 1 at a time, when i got to the boss all the tone returned and the volume increased. I cant believe how much this pedal kills the sound. Not sure if its always been this way or if theres an issue with the pedal. Anyway im very relieved to have found this. Demeter makes kick ass amps and when i talked to them before, they said the loop works best with rack gear at line level. Not where you really lose tone with pedals but things like delay come thru a little quieter and the line level shifter fixes that. Anyway, no more boss eq pedal as i dont use it much anyway.

[DeepEnd]

. . . Oh' date=' and Deep End, The reason you want the time based effects in the loop between the preamp and power amp is because you want all your gain and saturation to occur before those effects. Having distortion from an amp after an echo unit can sound downright awful. If you run your amp clean you're OK but if you want to use your amps gain channels and have those saturated notes "in the echo" the echo has to come after the saturation. . . .[/quote']

I'll take your word for it. Of course the OP was a bit more honest (emphasis added):

Reverbs and delays sound best for me in the loop . . .

He simply prefers it that way because it sounds better to his ears. Fine. Good enough for me.

 

Naturally, you want EQ to come after other effects, for example. But using the loop can also mean more and longer cable runs (unless you have everything in a rack) with the attendant potential for problems. Anyway, even the people who made the amp aren't worried about pedals being placed between the guitar and amp vs. in the effects loop (emphasis added again):

. . . Demeter makes kick ass amps and when i talked to them before' date=' they said [b']the loop works best with rack gear at line level.[/b] . . .

The loop is for rack gear, no mention of pedals. In any event, the OP has already discovered the source of the problem and eliminated the bum pedal so I hope we can put this to rest.

[WRGKMC]

I'll take your word for it. Of course the OP was a bit more honest (emphasis added):

 

He simply prefers it that way because it sounds better to his ears. Fine. Good enough for me.

 

Naturally, you want EQ to come after other effects, for example. But using the loop can also mean more and longer cable runs (unless you have everything in a rack) with the attendant potential for problems. Anyway, even the people who made the amp aren't worried about pedals being placed between the guitar and amp vs. in the effects loop (emphasis added again):

 

The loop is for rack gear, no mention of pedals. In any event, the OP has already discovered the source of the problem and eliminated the bum pedal so I hope we can put this to rest.

 

Actually time based placement order its something just about every pro guitarists and audio engineers know about. Many find it through trial and error, but there are actual scientific reasons why certain orders of placement work better and limit bad side effects that can be problematic. That of course doesn't stop anyone from breaking normal rules to get specific tones, but the "normal" placement has long been established in the industry

 

Here's some cool reading for you that you might want to explore. He probably explains it better than I can. I don't agree with all of his opinions but for the most part he's right on the dime when it comes to most technical aspects. I suspect this guy's a musician and audio engineer, but he does have allot of good insight on how many famous musicians got their sounds.

 

These are from the post amp effects placement chapters. The key item in this is having the time based effects after an amp or at least in the effect loop is it minimizes intermodulation which can be heard as a beating sound which is very hard on the ears. This guys into tube amps but the points are still valid for Mosfet amps which act like tubes and any solid state amp that drives a speaker

 

http://www.amptone.com/g182.htm

http://www.amptone.com/g074.htm

http://www.amptone.com/g159.htm

http://www.amptone.com/g054.htm

http://www.amptone.com/g077.htm

http://www.amptone.com/g006.htm

http://www.amptone.com/g114.htm

http://www.amptone.com/g120.htm

 

Here's the main page that has some great reading. Some of the stuff is dated and hasn't been updated but its good stuff for a guitarist to know, especially if he plans on doing any kind of professional recording or stage work.

 

http://www.amptone.com/index.html#effectssecn

[BowerR65]

I think you should try both ways because depending on what sound your looking for both can be good.

 

Right now im using a floor pod, i kinda like the sound this thing gives just using headphones so all i want is the power from my amp.

 

If i plug into the front of my amp from the floor pod ill get more hair and color from the preamp stage that im not wanting right now.

 

Still my power tubes and cabinet color the sound as well but i cant change that right now.