Cerrem mod

[ramp]

Just a quick question about the cerrem mod. For those who have done it, what wattage resister are you using? I know I'm dropping 600 volts across pin 3 of the tube sockets at full volume. Using ohms law, if I'm using a 500ohm resister dropping 600 volts, I'll need a 720 watt resistor. That sound correct? That's huge. I've got a master volume on my Metroamp marshall clone and I never run the master on 10 anyway, so I'm thinking I can get my with a 500 watt resistor, but I wanted to see if someone would chime in that has done this and see exactly what they have used. Appreciate any response.

Thanks,

[ramp]

Yawn...

[danjohn]

Hi!
I`ve tried that mod a few times, with different resistor-values. From 300 Ohms to 680 Ohms. The smaller the resistor value, the more you are lowering the volume and therefore more power across the resistor. For a 50W-amp I would use at least a 50W chassis-mounted resistor. For a 100W-amp I would use a 100W-resistor. Even though the full power doesn`t go through the resistor, the resistor gets very hot and you don`t want to take any chances, do you? I used some 20W-resistors in series-parallel to get the total power of 60W on a Marshall 50W-amp. 300 Ohms sounded the best, but the disadvantages were that the tubes ran very hot and one tube started glowing red and it wasn`t very loud either. But for a small period of time it was very fun and it sounded awsome.

[surrealamps]

go search Twistyneck and watch his video .. you dont need that high of a wattage res.