Orange TH30 questions

[Bieworm]

hi guys

I plan on building the TH30 soon. But I'd like to build only the clean channel and want to ommit the effects loop.
Is leaving out the effects loop going to impact the sound? It's tube buffered, and a substantial part of the circuit. Or shouldn't I worry about that?

thanks

[acheld]

I think it will work, with some caveats.  I'm not the guru here, but it looks like a straightforward amp in the absence of the effects loop (with of course your four glorious EL84 output tubes).

I assume you are looking for a very clean sound here.  Your signal into the PI will be attenuated by your tone stack, and to me it will be anemic.

Personally, I'd suggest adding a gain stage and a Master Volume similar to Doug's BJ Conversion schematic -- this is a proven design and works well, even with a slightly altered tone stack as in your schematic.

[Bieworm]

I think it will work, with some caveats.  I'm not the guru here, but it looks like a straightforward amp in the absence of the effects loop (with of course your four glorious EL84 output tubes).

I assume you are looking for a very clean sound here.  Your signal into the PI will be attenuated by your tone stack, and to me it will be anemic.

Personally, I'd suggest adding a gain stage and a Master Volume similar to Doug's BJ Conversion schematic -- this is a proven design and works well, even with a slightly altered tone stack as in your schematic.

Thanks. It's for a friend and he wants a clean pedal platform. He owns a TH30 at the moment but he wants a smaller lighter combo with less features. The OD channel is not requested for he uses only pedals for that.

[nandrewjackson]

+1 for the extra triode stage after the tone stack.


It won't be an "orange" anything after that really, but close enough to have a conversation about it being a modded version of something-or-other.


It'll be one heck of a clean, stompbox friendly tube amp !

[Bieworm]

+1 for the extra triode stage after the tone stack.


It won't be an "orange" anything after that really, but close enough to have a conversation about it being a modded version of something-or-other.


It'll be one heck of a clean, stompbox friendly tube amp !

Well it's not my call. My friend wants it that way. I just wonder if deleting the FX loop circuit is going to have impact on the sound. Otherwise it's totally wasted space and parts.. he doesn't use the loop...

[acheld]

Well it's not my call. My friend wants it that way.

I love it when (usually ill-informed) customers tell me how to do my job.   

[nandrewjackson]

I'm not hating on it at all. Sounds like a good custom project 😀

[Bieworm]

Well it's not my call. My friend wants it that way.

I love it when (usually ill-informed) customers tell me how to do my job. 

Lol.. but the guy already has a TH30 head + cab and uses only the clean channel.. and he's getting lazy. So ge knows what he wants. FWIW I always voice my amps for OD

[Keppy]

+1 for the extra triode stage after the tone stack.


It won't be an "orange" anything after that really...

Why not? The schematic in the first post shows a scratched-out gain stage on the effects loop return. It seems to me like that gain stage is essential for this amp to sound like it's supposed to. Granted, the cathode follower has a resistor divider to knock down the volume on the send, but there is much more gain on the return (56k / 1k5 = approx. 37:1) than there is loss on the send (4k7 / (4k7 + 15k) = approx. 1:4).


With the restored/added gain stage, all that's being left out is the cathode follower, but there's a leftover triode anyway, so it's not like leaving that out is of any particular benefit. If it were me, and I really wanted to keep the tone of the amp, I'd just build it as-is but without the loop jacks and extra pulldown resistors and coupling caps.


Unless someone's got a better idea for that cathode follower triode.