Thoughts on attenuation built into amps?

[JamieJ]

Hey all,

I came across the rob robinette page about mods for a deluxe reverb. It mentions a 25% or 10% power options using two resistors built inside the amp that are switchable.






It’s always a PITA messing about with an external attenuator so having it in the amp makes lots of sense. That being said, mounting it in a separate enclosure means so major changes to the amp and makes it easier to sell. BTW I think this amp is a keeper.

Keen to hear people’s thoughts

 

[lowpitch]

I personally wouldn't do it. Mounting two high wattage resistors in a 1590A or smaller with appropriately rated switches and jacks would keep the amp stock for possible resale and have the same effect, just a little less convenient. Also, purely resistive loads tend to suck high-end – like a lot. So it may not even sound very good.

 

[Asdrael]

A good attentuator made for the purpose will be a much better solution and scalable past 25W. And if you have more than one amp, you can just move it around, I see it as a bonus.

I am using a Two Notes Torpedo Captor 8 which I paid like 100€ and I wouldn't be happier with it really. Eats up my SLO 30 like a champ, with the added benefits of added outputs for recording etc.

 

[finebyfine]

I was surprised by how large my standalone attenuator ended up being when it showed up so I get where you're coming from but I do have to agree with what's been said - especially with how well it seems like Deluxe Reverb's retain their value. I would only do it internally if you try this resistive load externally and are sure you dig how it sounds enough to know it'll probably reduce the resale value of the amp by the price of an attenuator in the first place - I'm not sure if there are any decent tinier ones out there though.

 

[GAStan]

Another thing to consider is heat. Tube amps by their nature already generate a lot of heat. These large resistors literally convert electrical energy to heat. Placing them inside an enclosed chassis...personally I will not do it.

Plus to back up what has already been said, purely resistive loads are tone suckers (IMHO).

 

[spi]

Pretty easy to put this in a stomp box enclosure so you don't have to mod an amp. That's what I would do.

 

[GAStan]

But to be clear, I have learned much from Rob's pages and generally agree with him, just not on this.

 

[JamieJ]

Yeah I think you are all talking sense. I’ll build an attenuator in a separate enclosure.