Need gain and freq parts.

Todd00000

Todd00000

Enthusiast
Hello, first post. My EMP sub gain and freq controls were damaged in the last move. They now only work in a few locations. Where can I buy new ones? Thank you for your time.

Todd
 
William Lemmerhirt

William Lemmerhirt

Audioholic Overlord
Maybe parts express? Give ‘em a call.
 
TLS Guy

TLS Guy

Seriously, I have no life.
Hello, first post. My EMP sub gain and freq controls were damaged in the last move. They now only work in a few locations. Where can I buy new ones? Thank you for your time.

Todd
You need to open up the amp, and find the values of the potentiometers, and then order new ones from an outfit like Mouser. Then fit the new ones. Parts Express will not handle those types of electronic parts. You will need soldering skills to fix this.
 
lovinthehd

lovinthehd

Audioholic Jedi
The knobs look okay, what happened? This a before-only photo?
 
TLS Guy

TLS Guy

Seriously, I have no life.
The knobs look okay, what happened? This a before-only photo?
I can tell you what happened. He says the controls only work in a few positions. That means there was physical damage to the potentiometers. The damage is that the circular carbon resistor track on which the cursor runs is broken. Therefore the controls have to be replaced. So he needs to order new controls of the correct resistance and taper. The taper will be log or linear. I suspect the volume is log and the phase linear. The value and taper will be stamped on the controls.
 
highfigh

highfigh

Seriously, I have no life.
I can tell you what happened. He says the controls only work in a few positions. That means there was physical damage to the potentiometers. The damage is that the circular carbon resistor track on which the cursor runs is broken. Therefore the controls have to be replaced. So he needs to order new controls of the correct resistance and taper. The taper will be log or linear. I suspect the volume is log and the phase linear. The value and taper will be stamped on the controls.
Might have punched the back of the pots out- Shouldn't be too hard to repair, although some plate amps are fairly well sealed on the backside.
 
Todd00000

Todd00000

Enthusiast
I can tell you what happened. He says the controls only work in a few positions. That means there was physical damage to the potentiometers. The damage is that the circular carbon resistor track on which the cursor runs is broken. Therefore the controls have to be replaced. So he needs to order new controls of the correct resistance and taper. The taper will be log or linear. I suspect the volume is log and the phase linear. The value and taper will be stamped on the controls.
You're correct. It's hard to tell in the picture, but the knobs are at an angle. Thanks for the help. I'll call them soon.
Todd
 
William Lemmerhirt

William Lemmerhirt

Audioholic Overlord
Huh, I guess maybe PE wouldn’t work.
Digi-key might. I’ve sourced many things from there.
 
highfigh

highfigh

Seriously, I have no life.
You're correct. It's hard to tell in the picture, but the knobs are at an angle. Thanks for the help. I'll call them soon.
Todd
Who packed them?

Packing anything with control knobs needs to be done right and handling the packages needs to be done carefully.

Who dropped it?
 
lovinthehd

lovinthehd

Audioholic Jedi
If sufficiently packed the knobs simply wouldn't be in danger without a catastrophic event. Many simply don't pack well.
 
Todd00000

Todd00000

Enthusiast
Who packed them?

Packing anything with control knobs needs to be done right and handling the packages needs to be done carefully.

Who dropped it?
I was stationed in Italy, US Army Infantry Officer (R), and it was packed fine but I think ended up at the bottom of the pile and sitting the wrong way.
 
highfigh

highfigh

Seriously, I have no life.
I was stationed in Italy, US Army Infantry Officer (R), and it was packed fine but I think ended up at the bottom of the pile and sitting the wrong way.
If you mark the package with 'This Side Up' and draw arrows on the sides, some people actually pay attention. I haven't seen many lately, but....

Who was the shipper? If you're in the US and you were the one who shipped it to its destination , you can file a concealed damage claim, but they don't always help if it wasn't in the original packaging and not to toss salt on a wound but it's how they work- if someone ships something to you, THEY need to file the concealed damage claim.

Package engineering is a real thing and it's really best to keep all original boxes & packing, even if it's not convenient. To cut down on space, the foam/corners can be bagged and marked as to what they were used for (brand/model) and the tape on the box flaps can be cut so the box can be folded flat, with the exception of one or two boxes that will hold the foam and bags.

People look at me as if I have three heads when I say that I have all of the boxes for my equipment (other than a few used pieces) but when I have moved, not one piece has been damaged.

I will say that some items aren't packaged for individual shipment, only for being in a master carton or a shipping container with additional dunnage- that stuff needs to be packed better if it's going to survive the trip.
 
Todd00000

Todd00000

Enthusiast
If you mark the package with 'This Side Up' and draw arrows on the sides, some people actually pay attention. I haven't seen many lately, but....
Italians don't care. This was in 2017. :lol:
 
Todd00000

Todd00000

Enthusiast
Ok, y'all, the double pot is the freq 40-180 marked C50K, and the single pot is the gain marked A50K. They both have a sticker that says Volume MG. They are double ganged with 3 points on each gang. RBH Sound does not have replacement pots. Any help finding these for sale would be appreciated, as I have learned there are many variables to the thousands of pots for sale.
IMG_1556 22222.png
 
j_garcia

j_garcia

Audioholic Jedi
EMP is now RBH I think? They would probably be the place to start. Might be able to get the whole amp if the pots aren't available. And/or they might be able to tell you the exact PN for the pots.
 

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