The Amp Garage

Thanks ! great.

Maybe a typical newbie question; can anyone tell me what the input impedance of my 183 clone is ?

Is that simple to measure / figure out that by myself?

Thanks !

mhartman wrote:

chikov wrote:Thanks for the info - I will follow every step. However, how do I know if the phase is correct on the Output Transformer?

You will know. It will squeal loudly if it is out-of-phase. It will scare the hell out of you.

I had that.... you will notice. It did scare the hell out of me.

I made a 183 clone. I just took the best parts that I could get. It was quite a risk, I did not know what the end result would be. The amp is the best thing I ever heard, and the best that my friends heard. I'm very proud and happy that I did what I did. It was the first amp that I ever built. I'm p...

Thanks for your offer Erwin, it is quite a distance. Thanks Kassie for your explanation, I guess this is also usefull for others that have amp problems. Coming weekend I have some time again to check things. I did measure a lot already, all voltages are OK ( exactly as when the amp was working perfe...

I'm located in Hengelo......

It does sound better with my own 4 x 12 at home. Still I feel a loss of bandwith. I'm wondering if it's possible that the NFB resistor is blown. All the voltages are OK. Maybe I got the EL34's worn out, or did I wreck my OT and is there a way of checking this? It's great to have made this amp, but I...

So. I've checked everything. All the voltages are OK. The bias is exact how I adjusted weeks ago. Is it possible the NFB resistor is blown? Is there a way to measure if the OT is damaged? I feel I miss a great deal in bandwith, with a bit of a fuzzy sound. Swapped the preamp tubes, no difference. Sh...

Thanks for the advice. I'm going to try these things. I have a lot of measuring to do. I hope I will find the problem quickly, because the amp sounded like a million dollars.

The only way I could have ever build the amp was with all the great info on this site and all the contributions of you guys.

Thanks guys for your comments. I build the amp about six months ago. It worked perfect until someone used a ZVEX super hardon with max volume. It's the regular input. Thanks for suggesting the FET, it could have easily been that. But I used the normal input. I'm going to try that effects return ( th...

Hi,

I have made a #183 clone, But now I have a problem and need some advice. Someone used an effects pedal with a to large output and now the fine detailled sound of my amp is almost gone. Is this just the preamp tubes, or do I have a bigger problem?
It's all fuzzy and raspy now. terrible.
Thanks !

Thanks Dave, it helped. I'm lucky that it all works again. Gary, I did get a tiny spark ( o, this sounds dumb ) when using my multimeter and pulling away the probes. It was really small, but I think that killed the resistors. I'm very happy that the PT is OK. That would have been crap time and money...

Gary, Dave & others, thanks ! My amp is working again, the hum is all gone. I'm very happy and grateful for the help I got from you. It started with a loose heater connection between power tube and PI and this morning I found out that the two 150 ohm resistors to ground were both broke. Infinite res...

Gary is right. And it is fun to make your own.

Thanks Gary, I just measured the voltage between heater and ground. 95 volts ac. When I check the heaters, there is 6.4 volts on them. I'm going to follow what you said and disconnect and check the balance resistors. Could those be broken and the reason of the hum and the high voltage to ground? Hi ...