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erzane

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Hi,
Last time I did a serial config. to my speakers (pls see the image below) but the sound comes only when my volume pot is at max. I cannot fade the volume from low to loud since my volume pot. works like a switch. When volume is at min its off, and when volume is at max its on, but no way to make it loud gently like with a pot based on the pcb for exemple (if we take a scale from 0 to 12, volume min is 0 and volume max is 12, so I've to put my volume pot to 11 to have sound, before no sound at all, and from 11 to 12 the volume has no level difference, so like I said, it's like a switch...)

When I had only one mono speaker of 8ohm 3W, the same potentiometer worked fine (I also tryed it with a 4ohm smaller speaker). I could gently fade the volume from low to high like with any other pots, but now I have two speakers and maybe its too much for that pot (whitch is 500ohm / 1,3W).
Btw, my speakers are 6ohm each, maybe this pot cannot handle a total of 12ohm...
Maybe I should buy a vol. pot with more watts (maybe more than 5W)?
http://www.highland-audio.com/FR/Produits/Seis_1201.html
THANKS!!
 

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Your speakers should ideally be 4 ohms each.

The normal method this setup is used is to increase the volume on your PCB (50%) and then only use the cabs main volume pot to adjust volume.
 
I see. Do you think the cabs main pot did not function well because of the 6ohm of the speakers?
 
What kind of potentiometer does your cab have ?

Is it the original one ?

What kind of cab do you have ?
 
Originaly, the cab had a 500ohm / 1,5W TOCOS pot. (TOCOS is ex VIOLET Corp.), but I changed it for a 500ohm / 1,2W TOCOS pot. So, it's not the very original since 0,3W less and 3cm diameter smaller but same brand and same ohm. Btw. both pot. worked fine with my 8ohm / 3W mono solo speaker.
https://www.tocos-j.co.jp/jp/catalog/data/RA25_Series.pdf

Here are more pots from TOCOS, maybe I should choose another which wirks with two 6ohm speakers:
http://www1.enekoshop.jp/shop/tocos-netshop/item_detail?category_id=11323&item_id=62171

Cab: Jaleco Pony mkII 18''.
 

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Thank you for the detailed pictures!

The effect should not be that much of an issue.

I would try to find some stadard 4 ohm loudspearks and investigate with them.

On a JAMMA PCB it is the amplifier on the PCB which is doing all the work and 12 ohms might be a bit much.
 
Sorry but I have no idea when it comes to monitors
 
Ok, thanks anyway
p.s. btw, I tested my volume issue with my old 1,5W TOCOS vol. pot, only 0,3W difference and all work fine. Now I can set the vol. from 0 to max without any probleme. For the moment, I didn't tested another 1,2W pot, maybe mine is broken, I don't know yet, but I'll soon, like this I'll be sure if this issue cames from an insufficient wattage.

Edit: I tested my 1,2W pot with a single mono 8ohm 3W speaker and the issue still persists. That's the speaker I was using before and with it all was ok. I also made tests with a single mono 4ohm speaker, the one which fits the cab at the origine, same result (see the pics below). So my conclusion is that the volume pot seems to be broken. Maybe in my last setup the game boards volume pot was so high, also my main cabs pot, in the same time, and that made it blow. Anyway, it's a good news since all I have to do is to buy another one. I was strange to have a so big issue for only 0.3W though. So, it's not a matter of wattage, neither of ohms, since my pot is 500ohm, which is less much than the value needed by the speakers.
 

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