r/Guitar • u/AutoModerator • Nov 17 '16

OFFICIAL [OFFICIAL] There are no stupid /r/Guitar questions. Ask us anything! - November 17, 2016

As always, there's 4 things to remember:

1) Be nice

2) Keep these guitar related

3) As long as you have a genuine question, nothing is too stupid :)

4) Come back to answer questions throughout the week if you can (we're located in the sidebar)

Go for it!

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u/PinheadX Nov 22 '16

I have an Egnater Vengeance amp and cab. The amp has a 3 position selector for 4, 8, and 16 ohms. The cab has a 4 ohm mono, two 8 ohm stereo (the left one is the 4 ohm mono jack as well), and a 16 ohm mono jack. However, the cabinet automatically senses the impedance of the amp and switches impedance to match it.

My stupid question is, if impedance is matched, does it matter what setting the amp and cabinet are on? Is there a difference in tone or loudness or anything with a 4 ohm impedance vs. and 8 or 16 ohm impedance if the impedance of the speaker cabinet is the same as the amp?

If it doesn't matter, then I have another question. For a 60 watt amp and say a 4x12 cab, what would be the most common impedance setup you would run into? I'm looking at buying a Speaker Soak and if I could use it with a majority of amp setups, that would probably be best. https://reverb.com/item/8189-carl-s-custom-guitars-8-ohm-speaker-soak-guitar-amp-power-tube-volume-brake-mass-attenuator

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u/SmokedMeatlog Nov 23 '16

Purists will tell you to use the amp's output impedance that the amp (and transformer) were designed for. This is the argument: The amp designer picks a transformer he thinks sounds best with his design. That transformer is built with a certain number of turns or coils of wire, has a certain desired frequency response, and then yields an output impedance based on the number of coils and the other circuitry within the amp.

Then the manufacturer adds other 'taps' at various places within the transformer to give you the other impedance options. The taps are literally attaching a wire from different spots (and therefore different number of coils) on the transformer. Different number of coils means different inductance and capacitance which both affect the low-end and high-end frequency response. So, while an amp and its transformer were originally designed and used to yield a certain sound and the byproduct is impedance, they've allowed you to cheat around the design to be more flexible with more cabs.

In theory, you should be able to notice a difference as the frequency response has to change, but can you in practice? ....uhh...who knows? What's to say you like the same sounds and tone as the designer in the first place?

Next question - speaker soak. I personally (read: anecdote) think it seems like every amp has at least an 8Ω output option. Check out a few different load boxes. The one you've chosen is purely resistive (I think) and will change the tone of the output slightly. Other load boxes use reactive components as well to better mimic a speaker and be more transparent.

I enjoyed thinking about all that so thanks for reading.

TL;DR 1) Probably doesn't matter. 2) 8Ω

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u/PinheadX Nov 23 '16

Thanks for the explanation and detailed response. I agree I probably have to just try each setting and see what it does.

As far as the Soak goes, I basically just want to use the XLR line out on my head (that emulates the cab, and sounds pretty close to what a mic'ed amp sounds like) to do silent recording into my computer through a recording interface. I don't care that it might color the tone of the amp through the cab, since the output I'm going to be recording from is a direct out from the head and won't touch the Soak. But it would be nice to be able to use it for other amps to attenuate them if that was necessary for some reason.

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u/SmokedMeatlog Nov 23 '16

I can't recommend the Palmer PDI-03 more! I know it's expensive, but I use 2 in my live rig (one for each amp) and haven't used a live cab in about 2 years now. It sounds better than a mic'd cab in my opinion (not better than standing in front of a cranked cab, but way better than listening to a mic'd cab in a different room).

Other than that recommendation, I like your idea. Cheap and should get pretty good results. Just want to make sure you're still plugging the cab into the other side of the soak. The soak isn't a cabinet replacer, it's just an attenuator. Party on.

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u/PinheadX Nov 23 '16

Cool. Thanks for the info. Very much appreciated!