Peavey Deuce ... Should I Split it?

Dustin Kleingartner · Post by **Dustin Kleingartner** » 25 Jan 2016 12:27 pm

I should start by saying I don't know very much about the science of amps or speakers.

A few months ago I impulsively traded a $200 guitar for a Peavey Deuce VT with two 12" Black Widows (with the spiderweb design). Its a hybrid amp from the early 80s with nice reverb and a phaser that I don't use.

I am in love with the sound I get from this amp and my steel.

The two main critiques of this amp on the internet are that it is super HEAVY, and that it doesn't get a good overdrive tone.

Well, clearly I don't really care about the overdrive tone, and I thought I could live with the weight... but amps this heavy can be such a burden. I put wheels and a couple handles on it, and it is better, but still a terror.

So recently I have thought about the possibility of splitting this into an amp head and a speaker cab to make it more manageable.

So I guess my questions are:
How common is it to split a heavy combo amp?
Once split, will it need both BW speakers or could it work if I just made a one speaker cabinet?
Could I make a stand alone head and then build smaller individual cabinets for each of the speakers (so it would be 3 pieces total)?
What are other things that need to be thought about?

I just love how this amp sounds, and I'd like to make use of the BW speakers. I should probably just leave it the way it is... but that's not as much fun to think about

I appreciate any insights/opinions folks can offer!

Lane Gray · Post by **Lane Gray** » 25 Jan 2016 12:45 pm

Splitting it would help, but there's still a lot of iron in the transformers. They sound great but are a handful

Deane Cahoon · Post by **Deane Cahoon** » 25 Jan 2016 5:26 pm

Thanks for asking this Dustin, I was wondering the same myself. I have a Peavey Mace that I bought new in 1981, back when I was much younger and before 2 disk surgeries. The Mace is the same as the Duece but it has six 6L6 tubes (160 watts) instead of four (120 watts). I have the schematics, that is the only difference that I can see. Just for the record, I just weighed it and it's 80.6 lbs but mine doesn't have the BW speakers, just the lower end Peaveys. I think it ran around $400 new in Boston.

Anyways, the 2 speakers are wired in parallel and equal 8 Ohms, so that means they are 16 Ohms each. The amp has a jack for a 4 Ohm speaker (for a 4 x 12 cab, for example). If you plug into the 4 Ohm jack, it disconnects the main 8 Ohm jack. The 8 Ohm jack connects to the center tap of the output transformer while the 4 Ohm jack connects across the full secondary of the transformer. Since one speaker would be 16 Ohms, I don't THINK there would be any harm in using just one, plugged into the main 8 Ohm speaker jack.

Right now, I'm in the process of resurrecting a neglected steel (my first) and was hoping to use one of my existing amps to get started, so it's great to hear that the Deuce gives a good tone for you.

If you get to popping the chassis out of the cab, please let us know what the weight is. As Lane said, it will still be pretty heavy.

Dustin Kleingartner · Post by **Dustin Kleingartner** » 25 Jan 2016 9:46 pm

Thanks for the replies! Very encouraging.

So i looked closer at the speakers and they are BW 1201-8's ... which is confusing to me because wouldn't this mean that I should be plugging into the 4ohm AUX out even though the 8ohm out says MAIN OUT?

Maybe I'm not quite getting it...

So if these are 8omh speakers, could I just put one in a cabinet and power it with the Deuce as just a head? I feel like that should be just fine, if I were willing to go through the work.

Would it change anything if I wanted to run both speakers in their own individual cabinets?

thanks for the help.

Deane Cahoon · Post by **Deane Cahoon** » 26 Jan 2016 5:05 am

Hmmmm....maybe they aren't the original speakers? I would first look at the wiring: On mine, the cable from the output jack goes to one speaker and then a pair of wires jumps between the two speakers. The + of both are connected together, as are both -'s, which means they are in parallel. With yours, it would give 4 Ohms.
The other way they could be wired is 'series' where the output cable goes to the + of one spkr and the - of the other while a single wire connects the remaining + and - together; which in your case would give you 16 Ohms.

Assuming I'm correct and they have been changed out, then I would think that you should, as you said, plug into the 4 Ohm jack.

Also, your idea of using just one in a separate cab would be fine.

Side story: I studied Electronics in the early 80's - in one of our analog electronics classes, the instructor said "just be glad we don't have to study tube theory anymore". Half of the classes heads whipped around and gave each other horrified looks (the cool guitar guys who went to school so we could learn how to fix our stuff) while the other half cheered (the computer geeks). So...any of my suggestions are open for debate.

Jerry Overstreet · Post by **Jerry Overstreet** » 26 Jan 2016 8:20 am

http://peavey.com/support/searchmanuals/ Click the prompt to see the archived manuals..then find the Deuce. Here, the info states the speaker tap is 4 ohms and the external tap takes the imp to 2. Since the amp is designed to work this way, no harm.

The speakers are 1201 8 ohm wired in parallel. One 8 ohm cabinet should also be fine with a minimal loss in power.

Stephen Cowell · Post by **Stephen Cowell** » 26 Jan 2016 8:20 am

Not many amps change impedance taps when you plug in more speakers... turns out that the Deuce is one of them:

http://schematicheaven.net/newamps/peavy_deuce-b.pdf

Read Note 1 for the answer... your normal speaker connection is 4ohms, not sure why the call it '8'. When you add another 4ohms (that's why they call the second input '4') you go to 2ohms... so if you split your system (getting old, all of us) you should ensure that when you plug the original speakers in they should be paralleled into the original normal output... you definitely don't want to plug one into each output, which you could happily do with a Fender.

Now, if you add another 8ohm speaker, the output will switch to 2ohms... but all the speakers will still be in parallel... so the mismatch won't be bad at all (2ohms vs 2.66ohms). If you plug in a 16ohm speaker, most of the power will go to the original 2, and your mismatch will climb to 2ohms vs 3.8 (or whatever) ohms. Your external jack is designed for another 4ohm load, basically.

So feel free to split the system, but put double jacks on each speaker cab, and jack between them instead of running both to the amp.

Dustin Kleingartner · Post by **Dustin Kleingartner** » 26 Jan 2016 8:45 am

Thanks for all of the help! I think I am slowly beginning to understand this.

This is all very encouraging to me.

Once I get up the gumption, I think I want to build (or buy) a cab for the chassis, tubes, and reverb tank, and then build a 1x12 cabinet that is a bit wider than normal so the head can sit comfortably on top of it... and then probably put the other speaker in a different cabinet (normal 1x12), but probably only use both occasionally (running a cable between them, not both speakers to the head)... and I think it would be cool to have two size options for a 1x12 cab on-hand.

Ken Fox · Post by **Ken Fox** » 26 Jan 2016 2:13 pm

Attached is the schematic for the deuce VT series amp. The transformers outputs are main at 8 ohms and aux at 4 ohms. I was a dealer for Peavey and went to school at Peavey during the time these amps were made. They did in fact have two 8 ohm speakers in parallel for a total load of 4 ohms. They intentionally mismatched the load to the transformer, I questioned them about this when I was a dealer in south Georgia!

There were at least three version of Deuce amps. The first was a solid state amp. The next was the 240 series, hybrid with transistor preamp and the VT series with IC based preamp. Both the 240 series and the VT series had the same output design.

Ken Fox · Post by **Ken Fox** » 26 Jan 2016 2:21 pm

From the Mace/Deuce VT series manual:

Jerry Overstreet · Post by **Jerry Overstreet** » 26 Jan 2016 2:38 pm

....ah, yes. The 4/2 0hm taps info I quoted was from the original Deuce manual. I missed that Dustin stated VT.

Dustin Kleingartner · Post by **Dustin Kleingartner** » 27 Jan 2016 10:34 am

Even more helpful info... thanks.
It seems odd that they would mismatch the impedance like that, or that they would label the output like that (it's kinda confusing). Regardless of the goofy labeling, I guess it does offer some good options though... such as just using one of the 1201-8s in a wide cabinet.

joe long · Post by **joe long** » 28 Jan 2016 5:03 pm

In the early 80's I purchased a Duce with two 12 inch EV speakers from Maurice Anderson. Incredible sounding amp. Down side:82 lbs. Glad we had 2 wheel dollies.

Chris Sattler · Post by **Chris Sattler** » 30 Jan 2016 2:19 pm

Yes I've split one in the past.

I suggest an ax.

No I really did split one and it was the best thing I could have done with an old heavy Peavey. They do sound good.