#1
Hey guys i have an old Vox SS combo, that im now useing as a cab for my new Tube head, i took the guts out and am kinda reluctant to throw them away, can u guys think of something fun i could do with them?

it has a Graphic Eq, that would be cool if i could make into a pedal??

what u think UG?





#5
you could take the EQ out and make a pedal into it, sure.

you could also salvage those op-amps for use in distortion pedals.

you could take out the reverb section and do smt with that.

or you could just put it away somewhere and take parts from it as you need them.
#6
Quote by Invader Jim
you could take the EQ out and make a pedal into it, sure.

you could also salvage those op-amps for use in distortion pedals.

you could take out the reverb section and do smt with that.

or you could just put it away somewhere and take parts from it as you need them.


thats what im doing with my old amps
Gear:

Guitars:
BC Rich Warlock
Dean 88
ME682-In Progress
Amps:
Carvin SX300
Etc:
Clayton 1.0mm picks
Planet Waves cables.
#7
I like the idea of putting the EQ into a pedal and using the reverb section for something...

...but that sounds pretty cool, though I can't find much information either.

Not much else you can do. I'll take it.
Amps
Randall RG50TC, Roland Cube 15x

Guitar
LTD MH-100QM, Washburn X12

Effects and Etc.
Ibanez Weeping Demon, Boss FV-500H, Ibanez TS7, Ibanez PH7, dbx 31-band EQ, ISP Decimator
#9
Quote by abyssspecter
maybe add the reverb to your amp?



well ide like to make a reverb pedal, as i dont wanna touch my new amp, cuz kranks have a life time guarantee and i dont wanna void it.

But i have had a closer look and the pcbs, and im pretty dam confused as to how to do it, so i might just make a head out of it and sell it or use it for something else i dunno what
#10
The bit with the big heavy transformer is the power supply and the power amp. you could use this as a slave amp to power an extra speaker or a powered monitor if you sing.
Beware the big blue pots, they are the power smoothing caps and they can store enough charge to hurt you quite badly and continue to do this for up to several hours after the amp is switched off.

The bit with the graphic on is the pre amp. It won't work without a power supply but you might figure out how to connect a battery to run it off or build a new supply. Nowadays it is easier and cheaper to buy a simple plug in power supply as supplied with a lot of consumer electronics. It will be almost impossible for you to separate the graphic from the rest of the circuit board unless you are very knowlegeable, but you could use the whole pre amp as an effect which would give you graphic,reverb and overdrive.

Having said that I would probably just build a case and keep it as an emergency head then you can restore your combo at some stage, sell it and put the money to a new cab.
#11
Quote by Phil Starr
The bit with the big heavy transformer is the power supply and the power amp. you could use this as a slave amp to power an extra speaker or a powered monitor if you sing.
Beware the big blue pots, they are the power smoothing caps and they can store enough charge to hurt you quite badly and continue to do this for up to several hours after the amp is switched off.

The bit with the graphic on is the pre amp. It won't work without a power supply but you might figure out how to connect a battery to run it off or build a new supply. Nowadays it is easier and cheaper to buy a simple plug in power supply as supplied with a lot of consumer electronics. It will be almost impossible for you to separate the graphic from the rest of the circuit board unless you are very knowlegeable, but you could use the whole pre amp as an effect which would give you graphic,reverb and overdrive.

Having said that I would probably just build a case and keep it as an emergency head then you can restore your combo at some stage, sell it and put the money to a new cab.


hey pill thanks for the reply

i know about caps and what not, im not a complete n00b when it comes to electronics etc..

but i think this is a bit out of my league.

however your idea of useing the preamp section, i quite like, thats just the front panel right?
#12
Yep. but as I said you need to sort out some power if you want to use it on its own. The power runs from the connector I can see along what are probably the thickest tracks along the circuit board. You need to either track down a schematic/circuit diagram or identify them and connect everything up and find out what voltage it runs at with a meter.
#13
Phil, you are correct about the filter caps but only if this was a tube amp. This is certainly NOT a tube amp so those caps and every other cap in there is already drained a couple of seconds after the power switch is turned off. There is nothing to worry about. Even if those caps were still hot (which they are not), they'd only be holding smt around 25 volts. you won't even feel that.

tubes stop conducting as soon as the cathodes cool down, but SS devices cotinue to conduct. Therefore they drain the circuit themselves. the power switch breaks one or somethimes both of the wires of the power cord, so turning an SS amp off is just exactly like unplugging it.
#14
Quote by Invader Jim
Phil, you are correct about the filter caps but only if this was a tube amp. This is certainly NOT a tube amp so those caps and every other cap in there is already drained a couple of seconds after the power switch is turned off. There is nothing to worry about. Even if those caps were still hot (which they are not), they'd only be holding smt around 25 volts. you won't even feel that.

tubes stop conducting as soon as the cathodes cool down, but SS devices cotinue to conduct. Therefore they drain the circuit themselves. the power switch breaks one or somethimes both of the wires of the power cord, so turning an SS amp off is just exactly like unplugging it.


Because this is a safety issue I ought to make things clear. The power rail for a 100W into 4ohm SS amp is 70V. This will be be higher for amps that deliver this into 8ohms or which have higher outputs and a little higher if it is an FET output stage.

This is however a DC voltage which hurts a lot more than a mains shock and I am stupid enough to speak from experience. A DC shock can make all of your muscles in the electrical pathway through your body contract at once which is not at all pleasant.

The capacitors will discharge slowly through the circuitry after switch off but how quickly will depend upon the exact design of the amp and power supply and the size of the capacitors. Some designs of amps still retain significant charge for remarkably long periods, some discharge in a few seconds. Again I know this from direct experience. If anyone pokes around inside a power amp they need to know how to safely discharge a power cap. Try this http://www.acmehowto.com/howto/appliance/refrigerator/check/capacitor.php
#15
I know what electricity does to someone's body and I know how it acts.

Thought this was a practice amp, not a 100w. I guess i'll have to take your word for it, though.

The power rail for a 100W into 4ohm SS amp is 70V. This will be be higher for amps that deliver this into 8ohms or which have higher outputs and a little higher if it is an FET output stage.

I'd like to know how you know this.
#16
Quote by Invader Jim



I'd like to know how you know this.

I've no real idea whether this is a practice amp or not, I just thought having told the guy to play around with the power amp I ought to warn him about the power supply.

I used to build amps and sell them and I've even done a bit of design and loads of repair work. As to the voltage a 70V rail lets you swing roughly 30V +and- across the speaker, equivalent to 21.4V RMS. Power=V^2/R .

The rate at which a cap discharges depends upon the capacitance and the resistance of the circuit it discharges through. Smoothing caps in transistor amps tend to be 4000uF or more which is much bigger than those of valve amps so they will hold their charge longer (depending upon the exact circuit) though the voltages are much lower. Some will discharge in a few seconds but some will have significant charge an hour after switching off.
#17
This may be going out on a limb, but you could take the copper wire from the transformer, and make a custom pickup from random scratch materials. Heck, you could test your creativity, and try to make a guitar from materials lying around.

But if you would like to make a cool pedal or something, you could use them to make a distortion pedal, or whatever.