How to Mod a Carr Slant6v Lead Channel

[soulfixinman]

Anyone have an idea which amp model schematic I could use as a starting point to trial and error mod the lead channel of a Carr Slant 6v.
This is one of the early one and with 4 tube stages I can't believe how poor it sounds, original preamp tubes and no mods done to it yet.

[soulfixinman]

Here is the Carr Slant6v drive channel at the bottom v3 and v4.
The circled components have pencled next to them the value of the component in my amp compared to this schematic which is the 2004 version of the amp.
I am still looking for any ideas to get this channel to smooth out.

CarrSlant6v.png

[tictac]

I take it to mean by "smoothing" out you mean lowering the brightness and maybe lowering the gain a bit as well.

The places I'd start with for brightness is:

1) the .001 across the Volume control - remove it and try other values from 100pF to 220pF. Put a 3 way bright switch in there if you want to control this value.

2) the .001 across the 470K grid resistor of V4 pin 2, try removing it and see if you like not having the extra brightness.

Gain: Seems like too much gain in this circuit, reminds me of a Torres high-gain splatty distortion mod. I'd start by doing 3 things...

1) remove the 33uF bypass cap across the 1K in V4, you can put it back later if you want the extra gain, but you really don't need it.

2) on the 3 x 470K network in front of V4 pin 2, reduce the gain by changing the 470k going to ground to 220K

3) the 5K cathode resistor on V3 pin 8 change to at least 10K, you can experiment with values between 10k and 22k but 10K would be a good starting point.

You can tell the designer was having problems dealing with too much treble, he bypassed the plate and cathode on V4 with those 250pF to try to compensate by bleeding some HF to ground. You shouldn't need that 250pF on V4 pin 8, try removing it after you do the other mods and see if you like...

Let us know how it turned out...

TT

[soulfixinman]

I still have not modded this amp, what I was looking for from the drive channel was to make it less Marshall and more Dumble like.

[da Geezer]

It might help if you could post a larger version of the schem....I have a hard time making out the values.

Geezer

[xtian]

Zombie thread! I just got to play a Carr Slant 6v, and I am impressed by both channels, and the extremely strong reverb section. Wow! Anyone can find a better schematic?

[Colossal]

I have this one. It's kind of um...compressed.

Carr Slant 6V Schematic.gif

[xtian]

Thank you!

Here, I "unsmooshed" it for you.

Carr Slant 6V Schematic.png

[Colossal]

There is still compression in the power supply

[T Wilcox]

6 preamp tubes using DC heaters with only 1000uF of filtering? Is this correct?

[pdf64]

Zombie thread! I just got to play a Carr Slant 6v, and I am impressed by both channels, and the extremely strong reverb section. Wow! Anyone can find a better schematic?

The reverb may be a bit stronger than a typical BF / SF due to the 4M7 dry mixer resistor in the wet - dry mixer at the grid of the clean channel’s 3rd stage; typical Fender value being 3M3. The early DR AA763 had the 4M7.

The overdrive channel looks pretty similar to your 2204?

Did you try a newer model with reverb on both channels? It would be interesting to see how that was done, without it affecting other stuff. I guess the simplest way would be to make the circuitry on the clean channel after its 2nd stage anode common to both channels. With a bit of tweaking that should work, though with that method, the perceived reverb levels, when switching channels, can seem to change.

The fx loop is pretty nasty

If you are playing at high volume, the effects send signal level may be very high—high enough to overload some of the effects in your effects chain

I bet
The newer version doesn’t have an fx loop.
https://carramps.com/products/slant-6v

[xtian]

I played sn 0464. Reverb was on both channels, very nicely implemented. The boost switch causes a big jump in volume, more than a simple addition of cathode bypass would warrant. I may have to borrow this client’s amp to sketch it out.

[pdf64]

... I may have to borrow this client’s amp to sketch it out.

That would be great - enquiring minds are keen to know