Warning, Potentially stupid effects loop question

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Kopfjaeger
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Warning, Potentially stupid effects loop question

Post by Kopfjaeger »

OK, just what is an effects loop circuit for on an amp head? Looks like two 1/4 inch female jacks on the head. How is it used??

Thanks in advance.

Sepp
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cassius987
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Re: Warning, Potentially stupid effects loop question

Post by cassius987 »

It's a way of injecting your effects into the preamp stage without putting them between your bass and the input stage. Also some amps let you turn the whole loop on and off with another footswitch which can be handy for complex effects setups.

Send>effects>return.
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jps
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Re: Warning, Potentially stupid effects loop question

Post by jps »

Effects loops can be located in different parts of the circuit, which may partly determine just what kind of effects/devices can be used in them. Some are right after the first gain stage (usually before the input volume control, some pre-EQ, some are basically a preamp out/power amp in junction. There is also the series/parallel concepts, such as what SWR pioneered (I think they did on bass amps, anyway) with an Effects Blend control so you can mix the straight bass signal with the effected signal for the desired balance between the two, this being a parallel effects loop; these are great for adding a second independent signal, for example, a second preamp for another bass and be able to mix the two together.

With series effects loops the effect is placed in-line with the signal, best for devices such as compressors, where you do not want the straight, un-effected signal to "contaminate" the output from the compressor. Gallien-Krueger uses series effects loops in their amps; a common problem is that over time, if the loop is not used, the make-or-break contacts on the return jack that allows the signal to pass when it is not used can oxidize or otherwise corrode cause loss of the signal, simple enough to fix but it has cause much consternation among bassists (this can happen to any musician, really, with an amp that has a series effects loop). If you were to plug something into the return jack only, you will hear that signal out of the amp but the signal that is going into the "main" input and through the preamp section of the amp will no longer be heard as that make-or-break contact will be "broken" from the send side of the effects loop.

Personally, I feel that pedals should go between the instrument and the input of the amp, while rack type/(nominal) line level devices go through an effects loop; as usual, YMMV.
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Kopfjaeger
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Re: Warning, Potentially stupid effects loop question

Post by Kopfjaeger »

Jeff & Joshua,

Thanks for your explanation. Is there a clear benefit of using an effects loop over having your effects in line with your instrument?

Back in the day I owned a small DOD overdrive/preamp pedal, that most of my band mates hated. After I have switched back from my 4001 to a fender P, I was bored with the P bass sound and the 5 band graphic EQ on my Acoustic head was not getting me the sound I craved. It's the only effect I ever used up until quite recently.

Fast forward 25 years and I now own a Punch Factory, my Way Huge Swollen Pickle, and my Blackstone 2 channel MOSFET overdrive. Sometimes I feel like the Wizzard of Oz, manipulating the effects!! :lol: I keep the punch factory on all the time so would it be beneficial to pass that through the effects loop? I don't remember seeing any instructions with any of my effects stating if they are better served between the instrument or in an effects loop.

Sepp
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jps
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Re: Warning, Potentially stupid effects loop question

Post by jps »

Where the effects unit goes will, primarily, depend on the input/output levels it is nominally designed for, again this will partly depend on where in the amp's circuit it's effects loop is located. Compression is tricky as it's influence on the sound can vary depending on whether it is pre or post EQ on the amp. As I stated earlier, most pedal format units are designed for use before the amp's input.
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Grey
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Re: Warning, Potentially stupid effects loop question

Post by Grey »

I've used an amp without an FX loop for years and i've never had an issue with running pedals infront of the amp. Time based effects and digital processors (rack units) can perform better in a loop.
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Kopfjaeger
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Re: Warning, Potentially stupid effects loop question

Post by Kopfjaeger »

OK, thanks all. I suppose I'll stick to what I know and run my effects before the amp. I figured since my new head has one, I may be able to take advantage of some benefit. I'm just not seeing the wiz bang aspect of doing that with what I have.

Sepp
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jps
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Re: Warning, Potentially stupid effects loop question

Post by jps »

What new amp do you have?
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Kopfjaeger
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Re: Warning, Potentially stupid effects loop question

Post by Kopfjaeger »

Jeff,
Orange TB500 (tube preamp) to go with my new ultra lite Glasstone 2-12 Lill G cab. Both will be rated for 500w and weigh about 45lbs combined.

Sepp
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jps
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Re: Warning, Potentially stupid effects loop question

Post by jps »

Kopfjaeger wrote:Jeff,
Orange TB500 (tube preamp) to go with my new ultra lite Glasstone 2-12 Lill G cab. Both will be rated for 500w and weigh about 45lbs combined.

Sepp
http://forum.orangeamps.com/viewtopic.php?f=3&t=39386
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Grey
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Re: Warning, Potentially stupid effects loop question

Post by Grey »

Kopfjaeger wrote:Jeff,
Orange TB500 (tube preamp) to go with my new ultra lite Glasstone 2-12 Lill G cab. Both will be rated for 500w and weigh about 45lbs combined.

Sepp
I use an all-tube Orange head for my guitars and run all of my effects in front with no ill effects. As JPS was also quick to point out, the loop in that particular amp is for line-level signals. (For rack units and a small minority of pedals)
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Kopfjaeger
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Re: Warning, Potentially stupid effects loop question

Post by Kopfjaeger »

Guys,

Thanks a million for your helpful replies! I have no effect that either needs to go into an effects loop or should go through one. Just another feature that I won't use. Not that I'm unhappy with my pedals before the amp but there seems to be no benefit for me to change anything.

Sepp
Vintage/Classic Rickenbacker Enthusiast!
1972 4001 Jetglo
1973 4001 Burgundyglo
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