IMPEDANCE MEGATHREAD FAQ

A sub forum for our most useful repair, maintenence & upgrade threads.
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pocaloc
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Re: IMPEDANCE MEGATHREAD FAQ

Post by pocaloc » Tue Apr 26, 2011 11:56 am

I think you all have me to thank, in part, for this handy thead. :) I've been all over his ass with annoying questions. Thanks for being such a helpful/knowledgable resource.
Last edited by pocaloc on Fri Sep 09, 2011 3:26 pm, edited 1 time in total.

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Re: IMPEDANCE MEGATHREAD FAQ

Post by zhivago » Tue Apr 26, 2011 12:08 pm

I'm not sure how to change privileges specific to the forum, so I just made the edit for you, Brad :)

great writeup, by the way 8)
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pocaloc
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Re: IMPEDANCE MEGATHREAD FAQ

Post by pocaloc » Tue Apr 26, 2011 12:36 pm

When I tested the 70's bandmaster reverb that I just bought on my 16 ohm 1x12 cabinet, it was very quiet, and you could smell it heating up. When I brought it to a local store and tested it on his 4 ohm '65 Bandmaster 2x12 cabinet, I think with Oxford speakers, it almost blew the roof off and didn't seem to be heating up. So that 4 to 16 ohm difference really affected the amp.

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Re: IMPEDANCE MEGATHREAD FAQ

Post by jimboyogi » Tue Apr 26, 2011 1:11 pm

Great work Brad, an excellent write-up.

Is this a good place for information on power sharing in a multi-speaker array? If you have 4 speakers wired in 2 series pairs, then each pair paralleled, what proportion of the total power does each speaker see?

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Re: IMPEDANCE MEGATHREAD FAQ

Post by Dave » Tue Apr 26, 2011 2:09 pm

:-[ :-[

Is my recent Traynor thread the straw that broke the camel's back?

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Re: IMPEDANCE MEGATHREAD FAQ

Post by i love sharin foo » Tue Apr 26, 2011 2:14 pm

There's some ghost in the machine right now making it impossible for members to edit posts. Jay said he'll have a crack at sorting it as soon as he has some time.

PS, thanks for another superb write up Brad!
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Re: IMPEDANCE MEGATHREAD FAQ

Post by andrewdoeshair » Tue Apr 26, 2011 2:47 pm

All this knowledge is giving me a raging brainer.
If you wish to make an apple pie from scratch, you must first invent the universe. - Carl Sagan

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Re: IMPEDANCE MEGATHREAD FAQ

Post by Professor Plum » Tue Apr 26, 2011 3:57 pm

andrewdoeshair wrote:All this knowledge is giving me a raging brainer.
:D 8) :w00t:
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Re: IMPEDANCE MEGATHREAD FAQ

Post by Dave » Wed Apr 27, 2011 10:48 am

Brad, can you include some info about choosing the right speakers in terms of wattage? Do you add up all of the wattage ratings on all speakers being used to determine a proper amount?

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Re: IMPEDANCE MEGATHREAD FAQ

Post by sookwinder » Wed Apr 27, 2011 2:01 pm

Fender amps have a shorting jack on their speaker outputs for this reason-- If the speaker comes unplugged, it shorts the output transformer secondary, which will 'buy you some time' until you figure out that there's no speaker connected.

This is something I had not realised. When I went and looked at the schematics, I can now see the shorting jack (other than on the VC schematic - the VC has a RCA plug)

Thanks Brad for doing this thread.
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Re: IMPEDANCE MEGATHREAD FAQ

Post by jimboyogi » Thu Apr 28, 2011 1:05 pm

Cheers, thanks Brad :)

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Re: IMPEDANCE MEGATHREAD FAQ

Post by noisepunk » Sun Jan 15, 2012 1:59 am

Okay, curiosity question:

In terms of sound, is there any audible difference between lower impedance wired upwards (higher impedance) and high impedance wired downward?

I.E. 2 2ohm speakers wired for 4ohms vs. two 8ohm speakers...
They tried to give me advice, down at the record shop. I said "Sit down boys, this may come as a SHOCK. But alls I listen to, it's all freedom rock."

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Re: IMPEDANCE MEGATHREAD FAQ

Post by noisepunk » Wed Jan 25, 2012 3:19 pm

Hmm. Well thanks for answering anyway, maybe something to test sometime if I have the chance.
They tried to give me advice, down at the record shop. I said "Sit down boys, this may come as a SHOCK. But alls I listen to, it's all freedom rock."

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