"splitting"-one output to two...

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Level is usually a much stronger driver than impedance. Mixers are designed to feed amps, and they do it well. Most amps handle a range of inputs. However feed too high a level in, and it might be the last time you use it.

Ed
 
You're feeding preamps, though, not power amps. I don't know if this makes a huge difference or not, but still, plugging a mixer into a QSC and plugging a mixer into the input of a Marshall are two different things.
 
Yes they are. One excepts a line level input and the other a lower level input. Since the mixer output can be adjusted over the full range. one can usually find the right combo.

I've used this approach for some years with good results for a range of common guitar amps.

Ed
 
Ed- This link has a good tutorial on impedance http://www.whirlwindusa.com/tech03.html

Suffice it to say that impedance and amplitude are not the same thing. I'm glad that your setup works for you but that is not the recomended way of doing it and keeping a good guitar tone.

If impedance wasn't an issue they wouldn't make devices like the Reamp box. http://www.reamp.com/
 
Never said impedance and level were the same thing, and they're not. I am aware of the definitions of impedance as that was covered well in my BSEE program some 35 years ago. However level is usually much more important for things like damage to gear.

You might want to read the reference you supplied, as it contains some good information. For example:

“In order to preserve signal level and frequency response, it's important to drive equipment with a source signal that is lower in impedance than the equipment's input impedance. If the input impedance of a device is not significantly higher than the source impedance, the signal will be reduced or "loaded down" and its signal to noise ratio and frequency response will suffer.”

“As a general rule of thumb, it's wise to try and maintain an input impedance of at least 10 times the amount of the source impedance.“

Most all amplifies, including guitar amps, have a high impedance input. Most all mixers have a low output impedance. The above paragraphs are some of the reasons why this is the case, and why it works well.

You might also want to read the specifics from your other reference for the re-amp product. What it basically does is to match output and input levels. It is targeted towards professional recording where input/output levels are high (+4 based). It effectively reduces the output levels so that the result can then be correctly connected to a guitar amp (which is where the name RE-AMP comes from), which is usually a much lower level input device. To quote from their FAQ:

“Because the Reamp is transforming high-level audio into low-level audio there is no need for added power.”

The Re-Amp allows a guitar player to record a flat guitar sound (with no effects) and then cycle the recorded signal back through the complete guitar effects/amp chain during the mix down phase to produce the desired overall sound. This way you play it once, but can change the tone, effects, etc during mix down without the need to play it again.

In the case of using a small mixer to front end a guitar amplified, the output level control is key as it allows one to tailor the output level of the mixer to the correct range for the input level of the amp. Most power amps are line level based, where most guitar amps are lower level based.

Ed
 
Ed Dixon said:
Most all mixers have a low output impedance. The above paragraphs are some of the reasons why this is the case, and why it works well.
Ed
Click to expand...

Ed - I'm not trying to bust your balls on this but I want to make sure I understand.

I was under the impression that most mixers had an output of +4dbV ?

So if you plug into the HiZ input of your mixer (if it has one), and then your mixer is outputting at +4 which is higher than what the gtr amp expects, but you use volume to try and control any distortion that this might cause......How can your tone not be affected ?

Also your quote from Reamp does more to support Tex's argument than it does yours.

"What it basically does is to match output and input levels. It is targeted towards professional recording where input/output levels are high (+4 based). It effectively reduces the output levels so that the result can then be correctly connected to a guitar amp "

Well...isn't that what your trying to accomplish ?

Again I'm not trying to bust your balls and if it works for you great..But I gotta think that it's not the best solution.
 
The value +4dbV refers to level and not output impedance. This corresponds to a default voltage level for input/output level ranges. This is also outlined in one of the earlier references:

“Secondly, let's define +4 and –10 level signals.
+4 and – 10 refer to the reference level used for 0VU.
A +4 signal has a 0VU reference of 1.234 volts AC
A –10 signal has a 0VU reference of .775 volts AC
Professional recording equipment uses the +4 balanced signal.
Consumer equipment uses the –10 unbalanced signal.”

Most mixers have an output impedance of about 150 ohms. Most amps have an input impedance measured in thousands of ohms.

Most mixers output a line level voltage when set to the default slider value. As the slider is lowered, a lower level output results. Most guitar amps expect a lower level signal. Most power amps expect the higher line level signal.

The re-amp unit is designed with guitar recording in mind. You have a hot guitar signal (that comes from the recorded track at +4) you want to run through the amp chain before mix down, and it works well for that. When you are dealing with a guitar to send to two amps, there is no hot signal present.

The original problem stated here dealt with splitting a guitar signal for use in two separate amps. Trying to just split a guitar signal into two cords that are plugged into two separate amp does not always yield good results. This is due to the fact that each amp also ‘sees’ the other amp through the same cord. Sometimes this works and sometimes it generates hum and other less than desirable results. In some cases the grounding cable will not solve the problem, asside from the fact that is's a little messy.

By connecting to a device like a mixer, it isolates the signals going to the two amps. It also gives you much more level control to balance the respective feeds to each amp, including EQ control. Since the output impedance of the mixer is well matched to the higher input impedance of the amp, there are no issues there. The result can be a very flexible setup.

The mixer approach is also very useful when there are two or more original inputs that need to go to the same amp. My rig includes both a stereo guitar effects as well as two different guitar based synthesizers. The mixer then has 6 total inputs to send to two separate amp inputs.

As has been said before, not all combinations work for all gear. One has to look at the problem at hand, the possible solutions, and pick the one that best fits. For some it's a simple A/B switch. For others it may be a mixer or other device.

Ed
 
Ed Dixon said:
The original problem stated here dealt with splitting a guitar signal for use in two separate amps.
Click to expand...

It also dealt with doing it cost effectivly. Can you use a mixer to split, Yes. You can also use a number of other stomp boxes that split it into a stero out. But I spent $19 on the Moreley splitter and made sure I grounded the amps good and I have a very clear and crisp signal.
 
Yes, and many times what you used is a very low cost way to split the signal, and works fine.

You can also get simple mixers for about $40, which is still a pretty low cost approach.

Ed
 
Where did you get the Morley unit for $19? On MF, and other similar sources, they are about $50.

Ed
 
Ed Dixon said:
Where did you get the Morley unit for $19? On MF, and other similar sources, they are about $50.

Ed
Click to expand...

took the words right out of my mouth, or the keystrokes right out from under my fingers, or something like that....
 
I got it at one of my local shops (Tripple R Guitar I believe). I also don't run the battery in it. All the battery does is run the lights.

Like I said, you can use most anything you want to split the signal. I have used a stereo phaser, a compressor, an effects processor and a number of othe things. As long as you have everything grounded well, you will eliminate hum. Running multiple amps has a lot of advantages. I have been doing it for years.
 
Ed Dixon said:
The re-amp unit is designed with guitar recording in mind. You have a hot guitar signal (that comes from the recorded track at +4) you want to run through the amp chain before mix down, and it works well for that. When you are dealing with a guitar to send to two amps, there is no hot signal present.
Click to expand...

There is no difference in the output of a recorder or a mixer. The REAMP box was designed to handle the change in impedance in both situations.

I can see your determined to argue this until death so I give up. You obviously have a handle on your rig and for your needs the mixer is probably a decent way to go. I don't even like pedals in the signal path so to each his own.
 
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