Picked up a CT OT a while back. I understand the previous owner modded it to make it more "pedal friendly".

There was a note with the amp reading:

"Change 150k slope resister to 100k, change the .002mf treble cap to 1000pf or 500pf, master volume 47p solder cap across two legs going to ground"

Would someone perhaps be so kind as to mark where these should be on the circuit layout so I can work out whether they've been done or not?

Also, what would each above mod acheive?

Thanks in advance!

I wouldnt worry too much about the first two alterations (treble cap and slope resistor values), unless the amp sounds really wierd. The 47p on the master volume pot - depending on the amps overall tone - could seems a bit on the high side. I have settled on 15p istead.

However, the most important tool isyour ears, so before heating up the soldering irion, LISTEN carefully to the amp and how it behaves with your guitar and gear, both at home and in a band/gig situation. Spend a a couple of month playing the amp, before deciding to change anything.

There was a guy at this forum, "jzucker" - and I don't mean to put him down -  but he bought/build an overtone amp and only played it for something like 2weeks, after which he decided that the amp should be modified. And he  began modifying the amp intensively and posting a lot about his mods. After a couple of month he gave in and sold the amp. This behavior (and not the person, 'jzucker') seems a little odd, because an overtone amp (or any decent Dumble clone amp) can be made to sound just as good as any original dumble amp. All you need is using your ears and a little patience

To tweak a particular amp, you don't get great results simply by following other peoples schematics.... no matter what you decide to change in the amp, the component values that wok with one amp, will not produce a similar result in the next amp. They all sound a little different due the a number of small differences in components. transformers, the construction (e.g. the length of wires), the particular tubes in the (pre)amp used AND the speakers AND instrument used with the amp. So trust your own ears and don't rely too much on what other people have used in their amps.