Re-visiting my old Peavey Backstage Plus guitar amp.

[DrNomis_44]

Thought that I would start a thread about re-visiting my old Peavey Backstage plus guitar amp, since I'm doing some work on it at the moment, I need to re-connect the speaker ( a Jensen C10Q 8 Ohm 35Watt Speaker I bought for it a couple of years ago) up to the amp chassis, re-attach four metal corner-protectors, and put some knobs on the pots.

As far as I know the amp is in working condition, I'll post some pics in this thread for you guys soon.

I also need to make a new footswitch for it too, yet another fun-filled project.


Update:

A quick test-out confirms that the amp is indeed still working.


And here's a pic of the amp set up on my kitchen bench, powered up(check out the blue power led):

18545


This amp features footswitchable distortion and reverb, as well as a built-in FX loop.

[Simon Barden]

I was round my friend's house this afternoon and he was commenting how Behringer seemed to have bought a job lot of the brightest blue LEDs they could find and put them on all their kit. He was trying to set up a little Behringer mixer so we could both play through one amp, but the blue power-on LED was so bright he couldn't read any of the legends for the controls round it. They might be fine for some applications but in others they are a right PITA.

[stan]

Glad it works Doc.
I've been looking at amp switching pedals (to choose between 2 amps or run both), and they seem pretty expensive. Surely a home made one wouldn't break the bank - got any diagrams for one?

[DrNomis_44]

Glad it works Doc.
I've been looking at amp switching pedals (to choose between 2 amps or run both), and they seem pretty expensive. Surely a home made one wouldn't break the bank - got any diagrams for one?


Yep, I think I posted a very simple circuit for an A/B Box in the non PBG gear section, although it will only allow you to switch between either one of your amps, I think it's in the DIY pedals thread if my memory serves me right.

[stan]

Yep, I think I posted a very simple circuit for an A/B Box in the non PBG gear section, although it will only allow you to switch between either one of your amps, I think it's in the DIY pedals thread if my memory serves me right.


Ah yes, sounds familiar, I'll have a look

[DrNomis_44]

Ah yes, sounds familiar, I'll have a look


Here's a link to the thread:

http://www.buildyourownguitar.com.au/forum/showthread.php?t=5291

[Simon Barden]

The thing you need to be careful about with simple A/B switchers are earth loops (substitute 'ground' for 'earth' if you want here). The expensive switchers ones have transformer isolation for one or both of the output connections, so that there is no duplicate earth path. There is a reason they cost more. If you use a basic A/B box, then you need to make sure that both amps are powered from the same multi-way mains board, plus any pedal PSUs, to minimise the length of the multiple earth paths. It also helps if your pedals are all powered from isolated power supplies. Earth/ground loops can cause an awful lot of extra noise, especially if you've got any digital pedals in your set-up.

Any decent basic A/B pedal should also connect the unused amp output connection to ground (when selecting only one amp), to prevent an open circuit connection cable on the unused amp picking up lots of hum.

There's no guarantee that you will get any hum with a basic set-up, I've used the outputs from a stereo effects pedal into two amps without any issues - but then they were all connected to the same power socket. But in an electrically noisy environment, things might be different. So to guarantee good noise-free amp switching, paying a bit of money for a good A/B box with isolated outputs is a reasonable investment, but for non-critical applications, a basic one can suffice. Remember that your guitar sound is only as good as the weakest link in the chain.

[Dedman]

Thanks Simon, I've tried using a cheap Loopi-Pedals one and have got a load of noise. I'll try again running everything from the same wall socket

[DrNomis_44]

Been trying out my recently fixed TS-808 pedal with my Peavey Backstage Plus amp, and found that it seems to work pretty well with the amp's overdrive, on it's own the amp's overdrive is a bit transistory, but I found that if I set the overdrive on the amp so that I get just a hint of breakup, and then use the TS-808 as a booster pedal, I get more of a Tube-ish kind of sound, if I then engage the switches on the Pre gain control and the Treble control, it seems to fatten up a bit in a nice way, and then adding a bit of reverb enhances it a bit more, pretty interesting considering that the amp is a Solid State amp.

I guess the art in getting a good sound from any guitar amp is really all about getting to know the amp and using your ears to tell when it sounds good.

In the words of Joe Meek (famous English producer of the 50's)..."If it sounds good,it is good".

[DrNomis_44]

Glad it works Doc.
I've been looking at amp switching pedals (to choose between 2 amps or run both), and they seem pretty expensive. Surely a home made one wouldn't break the bank - got any diagrams for one?


Today, I got inspired to do some restoration-work on my Peavey Backstage Plus amp after seeing it sitting un-loved in a corner in my little studio room, so this week and next week, I'm going to be working on restoring it to a giggable state, not much needs to be done to it though, and I'm going to be making a new footswitch for it that will include indicator leds, something that the original one I made didn't have, once I have the design worked-out I'll post a hand-drawn schematic here for other Backstage Plus owners, together with a write-up.


I'm also going to look at what I can do to tame the blue indicator led brightness down a bit, since I really want to keep the blue led for it's coolness, I have a good idea of what needs to be done, I just need to change the value of one resistor and that should fix it.

[Simon Barden]

You could even fit a small trim pot rather than a fixed resistor, so you can adjust the brightness as you wish.

[DrNomis_44]

You could even fit a small trim pot rather than a fixed resistor, so you can adjust the brightness as you wish.

Yep, that would work a treat I'd most likely use a ten-turn trimpot of at least 100k in value cause I think the Blue led in the amp already has a fixed 47k current-limiting resistor, I've got a nice Jensen C10Q speaker to put in the amp, I just need to find some spare nuts that'll fit the speaker mounting-bolts cause it's missing three of them.


I've found that in practice those modern super-bright leds don't need a whole lot of current to glow at full brightness, less than a milliamp.

I just checked the led's current-limiting resistor and I did indeed use a 47k/1% 1/2W metal film resistor.


Okay, I have to be honest here, I added the blue indicator led because I wanted the amp to look cool, not me....I'm the complete antithesis of cool.....hahahaha.....

[DrNomis_44]

Update:


Just been working on making the new footswitch for my Peavey Backstage Plus amp, seems to have gone without a hitch, but I won't know for sure if it is working properly till i finish working on the amp itself.

[DrNomis_44]

Update:

Finally finished all the restoration work on my Peavey Backstage Plus amp this afternoon, everything seems to be working great, including the footswitch.