Crazy amp question (for techs)

Cory_Dylan

New member
The Classic 30 uses a 16 ohm speaker and has an ext. speaker jack for 16 ohms. If I took those two wires going to the speaker, and wired them to the ext. speaker jack inside the amp, would that not put the 2 outputs in parallel therefore make a single output for 8 ohms?

I know it sounds crazy but I would like to do this if it's possible. Thanks bros!
 
Re: Crazy amp question (for techs)

Really noone informed has any input on this?

I just want to know what would be the safe way to do this.
 
Re: Crazy amp question (for techs)

There shouldn't be any harm in it SO LONG AS THERE IS ALWAYS A 8 OHM SPEAKER CONNECTED.

However my only concern about hooking two leads from a power source to a load is that I do not know how current direction is guarranteed to go the right way. 2 LOAD leads to a power source just makes a parallel circuit but I'd agree that what you are talking sounds kinda iffy.

Are the jacks already parellel? Series? If you know then it shouldn't be too hard to find out what the ext speaker impedence would be if you just disconnected the internal speaker, plus this would be a much safer bet.
 
Re: Crazy amp question (for techs)

Are the jacks already parellel? Series? If you know then it shouldn't be too hard to find out what the ext speaker impedence would be if you just disconnected the internal speaker, plus this would be a much safer bet.

That's a good question and I'm really not sure. I guess I'll just stick with what I'm doing now. I have 2 jacks (one from the internal speaker wires and the ext speaker jack) hooked to 2 16 ohm speakers in a 2 12 individually. My goal was to wire the speakers in my cab up parallel for 8 ohms and just have one cable coming from the amp.

Is it even possible to change the impedance of an amp?
 
Re: Crazy amp question (for techs)

It's probably running 16 ohms normally, right? Then you add another 16 ohm speaker and it drops overall to 8 ohms. So, one way or the other, you're not matching the impedance accurately. Most good OT's can handle one degree of mismatch. Just don't drop from 16 to 4. This is the way all hte old Fenders were wired (that had extension jacks, cept they were 8 ohm to 4 ohm).

If you take a look at the jacks from the inside, I'm sure they're just gang wired together. So, there's only one set of secondary taps coming off that Output Transformer.

So, the original crazy question was basically crazy as the wires running to jack 1 are already wired to Jack 2. (99% accurate guess, I'd guess) :)
 
Re: Crazy amp question (for techs)

It's probably running 16 ohms normally, right? Then you add another 16 ohm speaker and it drops overall to 8 ohms. So, one way or the other, you're not matching the impedance accurately. Most good OT's can handle one degree of mismatch. Just don't drop from 16 to 4. This is the way all hte old Fenders were wired (that had extension jacks, cept they were 8 ohm to 4 ohm).

If you take a look at the jacks from the inside, I'm sure they're just gang wired together. So, there's only one set of secondary taps coming off that Output Transformer.

So, the original crazy question was basically crazy as the wires running to jack 1 are already wired to Jack 2. (99% accurate guess, I'd guess) :)

So what you're saying is, the wires going to jack 1 are coming from the same place as jack 2? So, if internal speaker is connected, the ext. speaker jack is still running to 16 ohms, but if you run that to a speaker, the overall load becomes 8 ohms which is a mismatch. So basically the only way to get a correct load with a 2x12 is to have 2 8 ohm speakers wired in series.

But, being in the case that I'm already at one degree of mismatch, if I wired the speakers in the cab in parallel, plugged them into one cable I wouldn't be hurting anything more than I already am, right? What are the risks of doing this/what I am now?

thanks scott!!
 
Re: Crazy amp question (for techs)

But, being in the case that I'm already at one degree of mismatch, if I wired the speakers in the cab in parallel, plugged them into one cable I wouldn't be hurting anything more than I already am, right? What are the risks of doing this/what I am now?

thanks scott!!

Pretty sure you'd go down to 4ohm then.
 
Re: Crazy amp question (for techs)

Pretty sure you'd go down to 4ohm then.

Well, assuming theres no internal speaker. If there was an 8 ohm speaker inside the amp, and an 8 ohm load was added then it would make for 4 ohms. (If I understand what scott is saying) I'm talking about only using one jack..
 
Re: Crazy amp question (for techs)

Unplugging the internal speaker and running an external cab at 8 or 16 ohms would probably work, ASSUMING all that other crap I wrote earlier was ACCURATE.

It appears 16 ohms is the preferred load for this amp if the internal speaker is 16 ohms.
 
Re: Crazy amp question (for techs)

I think I'll wire my cab up in series then. It'll be much less of a pain. I know the old saying goes "If it ain't broke don't fix it" but I think I'll be OK.

Thanks a lot for your help. I guess if my amp blows up and burns my house down I'll know who to blame ;)
 
Re: Crazy amp question (for techs)

Hey, you're in oklahoma, probably an improvement on the house.... ;)

<ducks to miss the haymaker punch!> :)
 
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