Reduce an amps compression?

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Hey guys. I recently had an old Traynor modded to Soldano SLO spec. I know the Soldano circuit is based heavily on clear cascading gain stages and that’s what makes it so defined and natural.

It really is a phenomenal distorted sound but because it isn’t a real Soldano, sometimes I feel like it’s TOO compressed. On lower single notes it seems to fart out as opposed to jump out the way I’ve heard Soldano amps do in recordings. To be fair I’ve never owned a real Soldano so can’t compare and I know a modded 1k amp doesn’t compare to a 4K amp.

The gain is absolutely wonderful, well defined and brutal. It’s more clear than I’ve ever heard any other high gain amps. For single notes on the higher register everything jumps, and for chords everything rings out fantastically. I was wondering though, if I had replaced a 12AX7 with something less gainy, would I be able to better control the compression levels as well? I’d lose gain I know but the circuit has AMPLE amounts of that. The SLO circuit is so dependent upon all the parts involved. My thought was that Mike uses and hand tests each amp/component to make sure it stays within his range ; If I use a lower gain first tube, would I be able to control the compression better?
 
That design IS compression.. The 1st gain stage runs a 220K resistor on the Plate which gives you more than twice the gain and compression compared to the typical 100K resistor used on most designs.. That sound is then amplified and squished thru the following stages.. You could use a lower gain tube in V1 like a JJ ECC83MG or a 5751 but the result is usually a lifeless dull top end.. 12AT7/ECC81's just don't seem to work in spots designed for 12AX7's for the same reasons with even less gain..

I have a Jet City 50 combo that's pretty much the same design and have been thru all this.. I modded the Plate resistors and Slope Resistors to get more openness, but it still is what it is..

If you really want open and dynamic in a high gain amp, you need to try a Deliverance.. It will humble you.
 
midnightlaundry said:
That design IS compression.. The 1st gain stage runs a 220K resistor on the Plate which gives you more than twice the gain and compression compared to the typical 100K resistor used on most designs.. That sound is then amplified and squished thru the following stages.. You could use a lower gain tube in V1 like a JJ ECC83MG or a 5751 but the result is usually a lifeless dull top end.. 12AT7/ECC81's just don't seem to work in spots designed for 12AX7's for the same reasons with even less gain..

I have a Jet City 50 combo that's pretty much the same design and have been thru all this.. I modded the Plate resistors and Slope Resistors to get more openness, but it still is what it is..

If you really want open and dynamic in a high gain amp, you need to try a Deliverance.. It will humble you.
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Agreed on the Deliverance, but an MCII will humble you beyond that. Most uncompressed amp I've owned.
 
Try dropping the gain way back and then hitting it with a boost pedal. Still adds compression but it will compress differently and may be more pleasing to your ears. That's how I ran my SLOs...I never put the gain past 5 and boosted it.
 
As mentioned above, lower the plate resistor value. It makes a huge difference in the feel, especially single notes. 100k will reduce the compression a lot.

It’s a 10 minute mod. Parallel a 100k over the 220k on a switch and you can even have it both ways. Yes, use a switch rated at enough voltage. I have a 3 way compression switch on my 800 that I modded myself. It’s extremely useful.
 
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This kinds of threads make me curious about just how different amps truly are from each other. A 6505, Dual rec, and an SLO. I know they sound different and parts play a huge role in things.. based on the schematics, I sometimes wonder if it’s just a few resistor changes apart or something haha.
 
Good catch on the 100 over 220. If you want closer to 100 just use another 220. I was posting off the top of my head.

You can even make it 3 way. You can do whatever value you want. Nothing is set in stone or a rule that you have to follow.

I use a 220+100 in series on the board in my 800 for a standard plate resistance of 320k. I have a 3 way switch with a 470k on one side for 190k total and a 1 meg on the other for 242k total. That amp tolerates a lot of plate resistance because it's not compressed to begin with. And of course there are a lot of other things going on inside.
 
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Tone Monster said:
I put a 5751 in my ENGL SE and it tamed it down perfectly
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I put a 12AT7 in V1 of my Superlead and it had the same effect. Much better tones and a less out of control gain beast past 2 on the dial
 
I love 12at7’s. I commonly use the JAN Philips 12at7wc in the PI slot of higher gain amps.
 
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