Having built a lot of these amps when using cap stack I move that tone board all the way over even up against the side of the chassis to allow more cap stack room.
Fowler, I actually thought about doing this early on, and I kicked myself for not going through with it.
Its not the end of the world though, might be a bit tight is all.
On that note, can hot glue be used to mount the filter caps?
What do you like to use?
RJ Guitars wrote:
Also, thanks for not using that steel chassis... not that you can't make a good amp from them, Fender and Marshall have done it for years. I was slightly saddened by Mark Fowlers comment that folks have been successful with creating good sounding Express builds in those chassis. I just hate to see any advancement of the idea of using steel for chassis because it is such a royal pain to work with... all intended as a light hearted perspective of course.
RJ,
Can you comment a bit more as to *why* steel chassis are inferior to (I assume) aluminum? Aside from working with the metal in a manufacturing context, is there not also some (refined, perhaps) sonic or conductive considerations?
Bob S wrote:I did one build that had a slightly skewed sweet spot.
Strange - but I figured whatever works best.
Bob,
Your observation would seem to point towards keeping one or both trannies unbolted -- but connected through the wire pass-through holes and with the amp powered up -- and THEN finding the position-effect "sweet spot" BEFORE drilling the mounting holes.....?
Well that is partly in jest... because it's wickeded no fun to work with compared to various aluminum alloys, and it's a bit heavy.
Otherwise the steel does couple to magnetic fields coming from the transformers but Fender, Marshall, and a bunch of others were quite successful in overcoming whatever issues come with it. Manufacturers like it because it's cheap.
It's not authentic for use in a Trainwreck but many things that we do are not either.
It's more of a personal issue for me to just deal with...
2tone wrote:Al has a better slew rate is supposedly one big reason. I believe this was Ken's thinking..
I've heard Derek Ferwerda talk about "Slew Rate" a lot concerning the EL84 tubes. That was something that supposedly Ken really liked about the EL84 tubes. It sorta made sense at the time but I've lost part of the meaning since then. IIRC it has something to do with how fast a tube responds... don't take that comment as anything significant since I don't recall much about it anymore. Can you you tell us what slew rate is and why it matters?
it has to do with how fast the amp responds to an input wave voltage, producing an output wave that can keep the high frequencies.. Materials and design elements are all variables I think. This is a simplified explanation, and I', not into the physics of it. Ken had stated that he liked the conduction properties of Aluminum better for a faster response, and I could see this, especially in the high frequencies. Express amp for example(Liverpool too) let thru lots of highs in order to get the harmonic output stuff.
RJ Guitars wrote:
2tone wrote:Al has a better slew rate is supposedly one big reason. I believe this was Ken's thinking..
I've heard Derek Ferwerda talk about "Slew Rate" a lot concerning the EL84 tubes. That was something that supposedly Ken really liked about the EL84 tubes. It sorta made sense at the time but I've lost part of the meaning since then. IIRC it has something to do with how fast a tube responds... don't take that comment as anything significant since I don't recall much about it anymore. Can you you tell us what slew rate is and why it matters?
2tone wrote:Al has a better slew rate is supposedly one big reason.
I call BS on this one.
What does an Al chassis have to do with the charging rate of a cap? If the chassis is used as a connection point between the power supply, power amp and other circuits well.... BUZZZ poor design.
[electron flow......It's not BS chassis metallurgy is part of the circuit...Maybe Ken was mistaken.??.. I doubt it...
quote="John_P_WI"]
2tone wrote:Al has a better slew rate is supposedly one big reason.
I call BS on this one.
What does an Al chassis have to do with the charging rate of a cap? If the chassis is used as a connection point between the power supply, power amp and other circuits well.... BUZZZ poor design.[/quote]
The chassis is not part of the circuit. Should not be part of the circuit. If it was, then the planet Earth would be part of the circuit, too, and you'd have to argue that amps have better slew rate in territories with certain zinc/granite/pyrite mixes, than over in County Y, where they're living on peat and volcanic ash, poor bastards.
I build and repair tube amps. http://amps.monkeymatic.com
I call BS on this one.
