Risson Guitar Amp

[CJ]

on the bench,

Risson ETA-100

 

[CJ]

got a bigazz Plush OP 4000 output transformer,

couple of PhillipsECG 6550's

 

[Matador]

Is that a JCM800(ish) clone?

 

[Brian Roth]

Wow! Plush amplifiers? I remember that brand from my youth and time working in the service dept. at a music store when I was in college. I can't recall the name for the type of upholstery on the cabinets....Kustom "tuck and roll" was similar but quite different. The Plush upholstery was like the seats in the booth at a diner.

http://www.plush-amps.com/P-cat9.jpg

http://www.plush-amps.com/cat_pages.htm#da_cat_2

Slogan "The Plush Rush".

Bri

 

[CJ]

Kind of like a Marshall with one input jack feeding a gain stage and another jack coming after that. I drew a schematic, none online, will post tomorrow.

There is so much gain that you can make it sound like a fuzz box.

You could put wheels on those Plush cabinets and enter them in a car show.

https://risson.com/artists/

 

[CJ]

there is a simple effects loop that does not require extra parts other than a few resistors,

the power tube B+ comes after the choke,

the gain was so high on the 1 + 2 jack that a 10 mv p-p signal was used.

 

[rock soderstrom]

I don't think I've ever mentioned this before, but I admire your schematic drawing skills, I wish I could do it as nicely. I think I will sample your style with an app.

 

[NoisyIndividual]

there is a simple effects loop that does not require extra parts other than a few resistors,

the power tube B+ comes after the choke,

the gain was so high on the 1 + 2 jack that a 10 mv p-p signal was used.

You forgot to designate HT C on the pre-amp tube Anode resistors, other than the first one.

Just saying, but I suspect you would like to know that.

 

[CJ]

got the B and C added, thanks!

also edited 2.2 K screen drop in supply to 1 K 5 W as the 2.2 K i stuck in there got mighty hot.

 

[CJ]

dual trace shots, on the transformer, primary vs secondary,

 

[CJ]

sq wave

 

[CJ]

weird telephone company input jack,

apparently Ben Risso worked at Fender and when they shut down, he took home some surplus parts and made amps.

 

[NoisyIndividual]

I can't see the bias pot in there, but I think I would be modifying it to loss of wiper means full bias, rather than no bias at all as in the schematic.