Custom 50 tone stack?

[dmatthews]

I love my Custom 50 paisley. Gigged the heck out of it.
When I went Kemper I decided to profile it, and I use that profile for some tunes.
Since Kemper Liquid Profiling came out I started to wonder what kind of tone stack it was fashioned after, and I'm coming up dry.
Those with a C50, or maybe H, I wonder what you think the amp/tone stack is fashioned after?
6L6 50w power, but whaddya think?

 

[Stephen J.]

I honestly don’t know what a tone stack is. So my response might be of no use. I thought the clean side was similar to a Bassman and the lead side was similar to a Plexi.

 

[dmatthews]

I honestly don’t know what a tone stack is. So my response might be of no use. I thought the clean side was similar to a Bassman and the lead side was similar to a Plexi.

Perhaps I chose my words poorly... That said, you answered with what I was looking for.
Cheers.

 

[andy474x]

I did some tinkering in mine, but never actually determined what the tone stack part values were, other than the tone slope resistor. That was on the smaller side, more in line with a vintage plexi spec-wise.

My overall feeling is that it’s a vintage inspired tone stack, but with a more modern amount of gain, which makes it easy to blow the low end way up quickly.

 

[RC Mike]

I've read different things. Particularly that there were three versions, with each sounding somewhat different from the others. I could never find out what the two revisions were for or what they changed.

I've got a Custom 50, but I don't have a great ear for saying X amp sounds like Y amp. Something that surprised me, though: I've got a Bogner Ecstasy Blue pedal that I only played with for a few moments. Why? Running into the clean channel of my Custom 50, it sounded an awful lot like the gain channel of the Custom 50. I'll dig things out and try it again this weekend.

 

[dmatthews]

Thank you gents, I now have a place to start!

 

[DreamTheaterRules]

Thank you gents, I now have a place to start!

What are you starting? Just curious.

I had one, and really liked it... However, the bias was supposedly WAY off on mine and my multi-meter was broken. The guy I sold it too LOVED it and said he couldn't believe how much better it sounded once he biased the power tubes. A year later, I asked about buying it back and he said "sorry, this is a lifer. Never selling this one!" Ok... so I had one but maybe will never know how good it should have sounded, even though it sounded pretty good.

But, to what Andy said, it was bass heavy and most all settings required dialing down the bass. And, while I never had a schematic to run numbers, what Andy said makes perfect sense in conjunction with what I heard when using the amp.

 

[dmatthews]

What are you starting? Just curious.

I had one, and really liked it... However, the bias was supposedly WAY off on mine and my multi-meter was broken. The guy I sold it too LOVED it and said he couldn't believe how much better it sounded once he biased the power tubes. A year later, I asked about buying it back and he said "sorry, this is a lifer. Never selling this one!" Ok... so I had one but maybe will never know how good it should have sounded, even though it sounded pretty good.

But, to what Andy said, it was bass heavy and most all settings required dialing down the bass. And, while I never had a schematic to run numbers, what Andy said makes perfect sense in conjunction with what I heard when using the amp.

The Kemper has a new feature called "Liquid Profile". Basically it is a more accurate gain/EQ section that is faithful to the original instead of the generic one classically assigned.
So quest is to find the tone stack/gain/EQ closest to the Custom 50 from a list of Liquid Profiles that are available.
So if the suggestion is that the clean channel is Bassman like, then I will apply the Bassman Liquid tone stack, and if the lead channel is Marshall like, then apply that tone stack.
This won't stop you from applying a Vox tone stack, or any other you want to try.

 

[DreamTheaterRules]

that's very cool. So... anyone got the schematic? If so, we can figure it out for you.

 

[dmatthews]

that's very cool. So... anyone got the schematic? If so, we can figure it out for you.

I find a tube chart... https://d159anurvk4929.cloudfront.net/documents/custom_50_tube_chart.jpg
This manual... https://d159anurvk4929.cloudfront.net/documents/2ChannelCustom_Manual.pdf
Haven't found a schematic yet...

 

[DreamTheaterRules]

I find a tube chart... https://d159anurvk4929.cloudfront.net/documents/custom_50_tube_chart.jpg
This manual... https://d159anurvk4929.cloudfront.net/documents/2ChannelCustom_Manual.pdf
Haven't found a schematic yet...

Yeah, I had both of those things. Need a schematic. Anybody got one?

 

[Em7]

I had my hands inside the "H" when I developed the batteryless LED footswitch for the "C" and "H." That top0logy has a cathode follower before the stack just like Marshalls and some of the tweeds. Some of the values may be slightly different, but it is not an exotic tone stack by any stretch of the imagination. A cathode follower before the tone stack is critical to the Tweed Bassman and the Marshall sound. A cathode follower is slightly less than a unity gain stage. It provides little to no voltage amplification. What it does is source current, which prevents the gain stages before the tone stack from being loaded down by the tone stack as they are in the Blackface and Silverface topologies. Leo and company threw away gain and midrange in their quest to keep the output distortion free in the black and silverface amps. It was only Leo's incredible frugalness that keep these amps from being more hifi. The iron in most Fender amps is undersized.