Pedals these days have gotten really good. Take something like the Ampeg SCR-DI for instance. Makes pretty much any amp sound like an Ampeg. Anyone ever try getting a random power amp, a good cab and running a pedal like this? Im thinking an older, used Peavey amp with a nice cab or two running the Ampeg pedal might sound pretty good on the cheap. Thoughts?
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Cheap power amp and cab with pre amp pedal?
- Thread starter mbell75
- Start date
As long as the SCR-DI line output can put out enough juice to drive the amp to full power it will work fine. The manual says it should work with external power amps, but does not say the maximum output level. So that makes it hard to say for sure if it will work.
The spec to look for on the power amp datasheet is sensitivity. Sensitivity is the minimum level required to drive the amp to full power. Sensitivity ratings vary from amp to amp, and some amps have a switch to change the sensitivity level.
Normally you look at the max output for the preamp and if it is more than the sensitivity rating for the power amp, you are good to go.
The spec to look for on the power amp datasheet is sensitivity. Sensitivity is the minimum level required to drive the amp to full power. Sensitivity ratings vary from amp to amp, and some amps have a switch to change the sensitivity level.
Normally you look at the max output for the preamp and if it is more than the sensitivity rating for the power amp, you are good to go.
dude told you what can make it not work.
I think we are talking about different things. I’m not trying to use the pedal to power the amp at all, that’s what the amp is for. All I want the pedal for is to make a Behringer or a Peavey amp sound like an Ampeg with the pedal. All I am going off are YouTube videos but it seems to make whatever amp it’s plugged into sound a lot like an Ampeg. So I was wondering about getting an Ampeg tone on the cheap.
Typically the output from a pedal will be at Instrument level. A power amp accepts a balanced line level signal to be able to drive the amp fully. Read post #2 again. 
Typically the output from a pedal will be at Instrument level. A power amp accepts a balanced line level signal to be able to drive the amp fully. Read post #2 again.
Why should a pedal have to power a power amp? I’ve never heard of that. Pedals just color the sound of an amp with EQ etc...All I know is my Fender Rumble sounds a lot different with my SansAmp Bass Driver in front of it and changes the sound. It’s not powering my Rumble. I dont see why a similar Ampeg pedal would be any different. Thanks.
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??? You asked specifically about using a "random power amp" in the OP. The Scramblers "line output" is line level, but there is not guarantee that it's hot enough to push every power amp to clipping because Ampeg did not publish it's maximum output level. The manual does say the XLR and 1/4" line outs are wired in parallel, but the XLR is 6dB hotter.
This is the pedal I’m talking about. I don’t need it to power or clip anything. All I need it to do is color a cheap Behringer or Peavey amp and make it sound like an Ampeg
https://www.musiciansfriend.com/amp...MI_52T6tyb4wIVkLfsCh3o8w3OEAQYASABEgJaVvD_BwE
Here's the manual I have been referencing. https://ampeg.com/pdf/manuals/SCR-DI_OM.pdf
Lot's of people use the pedal and love it. It may or may not work for you, depending upon what equipment you decide to use it with. Since you don't seem to grasp the technical matters I am trying to explain, the best you can do is try it out. Either it will work or it won't. Good luck and I will let myself out now. Sorry I could not be more helpful.
Yes it can be done but not every power amp will work well. Just try a decent one and be detached from the outcome. If dissatisfied, try a different one. I run a Sansamp direct into the power section of a GK amp. Works good.
wmhill
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The Peavey IPR 1600 power amps were pretty great and weighed about 7 pounds. I did hundreds of issue free gigs with one for several years.
Passinwind
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It doesn't. It has to drive it for the application you mentioned in your title though. To fully drive a power amp means having the ability to make it clip, otherwise you are leaving potential performance on the table. But in any case, pedal max output specs are notoriously unreliable as a metric for suitability with any given power amp.
Are we all on the same page here though? A power amp is not the same thing as a bass head.
Power amp is the bit that makes the big noise.
Preamp takes piddly instrument signal and turns it into something a power amp can use.
Pedals are all over the shop. Some can and some can't. Personally I don't like calling pedals preamps unless they can.
Preamp takes piddly instrument signal and turns it into something a power amp can use.
Pedals are all over the shop. Some can and some can't. Personally I don't like calling pedals preamps unless they can.
- Feb 12, 2006
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I'm going to suggest to the OP that instead of questioning and arguing about something the clearly do not understand, it would be MUCH better and productive for everybody for you to take the (correct) information you have been given by several members here and learn more about the relationship between an amp's sensitivity and how it may or may not be able to be driven to rated output by a pedal depending on the pedal's maximum rated output capability.
Many pedals are rated to drive at nominal instrument levels, with enough headroom to achieve -10dBu maximum output whereas many power amps need +4dBu input level to achieve rated output. There are some pedfals that will drive +4dBu, but these represent less than 50% of the pedals on the market IME.
Many pedals are rated to drive at nominal instrument levels, with enough headroom to achieve -10dBu maximum output whereas many power amps need +4dBu input level to achieve rated output. There are some pedfals that will drive +4dBu, but these represent less than 50% of the pedals on the market IME.
It doesn't. It has to drive it for the application you mentioned in your title though. To fully drive a power amp means having the ability to make it clip, otherwise you are leaving potential performance on the table. But in any case, pedal max output specs are notoriously unreliable as a metric for suitability with any given power amp.
Are we all on the same page here though? A power amp is not the same thing as a bass head.
Ah ok, now that makes sense. Ironically, a local GC just got the pedal in so I’m gonna go try it out today. Thanks
So here's my attempt at a simplified explanation...
- Power amps essentially have one big volume knob to control the level of output; they do not have a knob to control the level of input (<- important)
- Different power amps have different levels of "sensitivity" on their input. That means that if you were to send the exact same signal to two different power amp one might see that as a "whisper" and the other might see it as a "shout" (it just depends on the power amp)
- The amount of volume a power amp can output will be limited by the amount of signal that is coming in to its input. (i.e. "whisper" in "whisper" out no matter how much you crank the knob. "shout" in "shout" out and you can turn down the knob if it's too loud.
So, the key to understand is that the input signal going into the power amp has to be strong enough coming in to drive the the power amp so that it can amplify the signal on the way out. If the input signal that's coming in is too weak for that power amp then no amount of cranking the knob on the power amp will make up for that incoming weak signal.
All that being said, here's the summation...
- different power amps are designed differently, some are designed to work with weaker input signals, some are designed to work with stronger input signals
- some pedals will output stronger signals than others, some pedals will output weaker signals than others
- the key to making it work is to have a pedal feeding the power amp that outputs enough signal for the power amp to be "driven" enough so that the full volume of the power amp is available to you (which you can always turn down with the volume knob on the power amp)
- most pedals will NOT drive a power amp because they aren't designed to be used that way (pick any chorus, flange, delay, that you can think of)
- some pedals MAY be able to drive a power amp, it all depends on how the OUTPUT of how the pedal was designed pairs up with how the INPUT of the power amp was designed
- the pedals that are the most likely (but not guaranteed) to be able to drive a power amp are those that are intended to replicate the function of a preamp in a bass amplifier (because that's what preamps do, they take the instrument signal, do "stuff" to it, and then send that signal along to the power amp section of the bass amp. Its just in this case you're wanting to not use a bass amp that has a preamp/amp built into it and instead split those two things out where one is a pedal and the other is a power amp)
- Power amps essentially have one big volume knob to control the level of output; they do not have a knob to control the level of input (<- important)
- Different power amps have different levels of "sensitivity" on their input. That means that if you were to send the exact same signal to two different power amp one might see that as a "whisper" and the other might see it as a "shout" (it just depends on the power amp)
- The amount of volume a power amp can output will be limited by the amount of signal that is coming in to its input. (i.e. "whisper" in "whisper" out no matter how much you crank the knob. "shout" in "shout" out and you can turn down the knob if it's too loud.
So, the key to understand is that the input signal going into the power amp has to be strong enough coming in to drive the the power amp so that it can amplify the signal on the way out. If the input signal that's coming in is too weak for that power amp then no amount of cranking the knob on the power amp will make up for that incoming weak signal.
All that being said, here's the summation...
- different power amps are designed differently, some are designed to work with weaker input signals, some are designed to work with stronger input signals
- some pedals will output stronger signals than others, some pedals will output weaker signals than others
- the key to making it work is to have a pedal feeding the power amp that outputs enough signal for the power amp to be "driven" enough so that the full volume of the power amp is available to you (which you can always turn down with the volume knob on the power amp)
- most pedals will NOT drive a power amp because they aren't designed to be used that way (pick any chorus, flange, delay, that you can think of)
- some pedals MAY be able to drive a power amp, it all depends on how the OUTPUT of how the pedal was designed pairs up with how the INPUT of the power amp was designed
- the pedals that are the most likely (but not guaranteed) to be able to drive a power amp are those that are intended to replicate the function of a preamp in a bass amplifier (because that's what preamps do, they take the instrument signal, do "stuff" to it, and then send that signal along to the power amp section of the bass amp. Its just in this case you're wanting to not use a bass amp that has a preamp/amp built into it and instead split those two things out where one is a pedal and the other is a power amp)
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The knob on the power amp adjusts the input sensitivity, it has nothing to do with the output other than by the way of the input sensitivity.
Power amp input sensitivity for tared output is generally specified with this input level (or sensitivity) control all the way up.
Power amp input sensitivity for tared output is generally specified with this input level (or sensitivity) control all the way up.
I hope OP has got the power amp does not equal bass head memo already, or his head is going to explode.
Yes, that's a viable solution. I've used an Eden WTDI at numerous locations where I was forced to use their backline. The WTDI is a DI box that has a built Eden preamp with adjustable compressor built in. I just plug that rascal into the effects-in/effects-return of the backline amp and it bypasses the amp's preamp and just uses their power section.
I've made Peavey, GK, Ampeg, and MarkBass amps all sound like my Eden amp. I bought this because I was required to use a little Peavey 112 combo at a small venue and I just couldn't get a sound I liked out of the Peavey. This little box made it sound like my Eden gear.
I also used it as a DI to the board on a recent recording session where the studio wanted me to run straight to the board. They preferred that I use their DI, but I used my WTDI instead. After the session the engineer came out to see what I was using that sounded so good - really recorded beautifully. His comment was, "Doesn't Eden want to sell amps anymore?"
So yeah, find a preamp in a DI that you like the sound of, get yourself a decent cabinet, and worry less about how a particular amp sounds. As long as it has the power you need, and you have a good cab to receive the signal that DI stompbox with built-in preamp is really all you need.
My WTDI has gain and master, Enhance (I never use this when playing in a group), adjustable compressor, Bass, Mids (toggles between 500Hz and 2KHz - I boost it slightly at 500Hz) and Treble. It's also works great directly into the board with FOH.
I paid $150 for my WTDI. Here's a shot of it:
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