Point of 4 220pf treble caps in VHT Del EQ?

[Speedypancake]

Been studying schematics for various high gain amps and was confused by the EQ section for the VHT Deliverance 60 treble pot.

In most valve amps, it's standard to have a low value ceramic disc cap, eg. 220pf to 470pf at one end of the treble pot. But in this amp they show 4 X 220pF, arranged in a combination of series / parallel so the total capacitance ends back up at 220pf? So why not just use 1 cap? I'd thought it might have something to do with the working voltage, but each is rated at 1kV...

vht tone.jpg

[sluckey]

They compliment the use of four resistors for the slope resistor and also maintain a certain symmetry. Or the engineers got a bonus based on parts count.

[Speedypancake]

[pompeiisneaks]

They compliment the use of four resistors for the slope resistor and also maintain a certain symmetry. Or the engineers got a bonus based on parts count.

Or another option is the engineer knows they tend to fail often and fail in pairs so he's prepping to keep it working

~Phil

[thetragichero]

you sure wouldn't see this gross waste of components in a fender amps! there's gotta be a quarter's worth of unnecessary parts there!

[Speedypancake]

Thanks all - good to know there's no real sonic or design reason here. I did wonder if the schematic was wrong, but found an internal shot from an amp, showing the caps and all the 56K resisitors as well!

Maybe they weren't sure what they were going to put in there but already had 3 million pcbs on order?!

Forgot to mention_ Nice little notice there on pcb from the designer

vht2.jpg

[oj]

Can be a sonic reason caps in series sounds less hard .

[roberto]

One of the reason is to read alot of threads like this one and so to increase the number of lily white ass kissers. I'd do the same honestly.

Another reason can be, if they are metal film and are mounted in opposite directions, to counteract some small unwanted inductance of the resistors (talking about parallel ones), or microfonicity of the ceramic caps.
I have a VHT preamp and two VHT power amps (the 2:50:2 and the 2:90:2) and I have to say that the 2:50:2 is the best rack power amp I've ever had together with the Mesa Boogie 295.

[roberto]

Can be a sonic reason caps in series sounds less hard .

I've heard some users working/reengineering/cloning Engls claiming the same.
I've no first hand informations on this.

[Speedypancake]

Another reason can be, if they are metal film and are mounted in opposite directions, to counteract some small unwanted inductance of the resistors (talking about parallel ones), or microfonicity of the ceramic caps.

Not sure about that. The 4 X 56K slope resistors are also arranged in a similar way? VHT seem to like a lot inter-circuit cap / resistor switching to alter the tone, so I'm thinking it's more likely something they had in mind at the design stage but abandoned for production and stuffing 4 identical caps and resistors into the gaps was the easiest solution...

Or the designer was having an intimate relationship with the components rep..

I have a VHT preamp and two VHT power amps (the 2:50:2 and the 2:90:2) and I have to say that the 2:50:2 is the best rack power amp I've ever had together with the Mesa Boogie 295.

OK! Yours is bigger than mine

[roberto]

I know you are jocking, but i want to specify that I didn't say that to measure anything.
It was just to say that whatever reason there's behind the 4x4 arrangement, Fryette has always done excellent products out of the usual routes that most of the others follow.