Can you use ONLY the power amp section of the Power rack version?

Just turn off the stack section. But those preamps are going to sound pretty stale without a tube power amp (real or simulated). You can try feeding those preamps into a clean profile, probably will be a lot of trial and error.

Hi Jeff

Never tried it but if I did need to do that here’s what I would do:

First put direct profile of the valve power amp that you would use in the physical world and load that in the stack section.

The put the preamp(s) in Stomp D in a loop fx in front of it. That way you can still use up to 3 stomps in front of the physical pre amp and turn everything off and change to a totally dfferent rig is sing only profiles any time you want (even mid song).

Now the problemwith that; there probably aren’t any power amp nly profiles of the amp you want so you need to roll your own. If you don’t have the physical amp you stuck. You mentioned the 2:ninety as the sort of amp you would want to use. You need to find someone with one that you borrow to profile. However, the 2:ninety is essentially just a pair of 90w mark series simul-class power amp with so extra options. Find a mate with any mark series amp and profile the power amp only by sending the profiler signalin through the FX return.

As I say, I’ve never felt the need to try i but I am also a curious sort of chap and happen to have a Triaxis and 2:ninety sittng downstairs at the moment

I feel a little experiment coming up this afternoon

Evidence trumps theory. If it works I’ll upload the 2:ninety profile to RE for you to download.

WOW!!!!

The theory works in practice!

I love it when a plan comes together

I made 8 profiles of my 2:ninety connected to a Mesa 112 Thiele cab with an old '90's EVM12L in it. I used a cheap ART Z Direct passive DI box between amp and cab. I'm sure they would sound even better with a Kemper DI or Countryman but that ART did the job.

The signal chain went Kemper Direct Out > 2:ninety In set to Instrument level rather than line level as the signal from Kemper should be similar to a guitar hitting the amp.

All profiles are of the 2:ninety with output at 1 o'clock and presence at 12 o'clock.

Profiles are as follows:

1 - Full Power with no mode switches active

2 - Deep switch on

3 - Modern switch on

4 - Deep and Modern switches both on

profiled as clean amp with no cabinet

5 - Half power mode on.

6 - Half power with Deep switch

7 - Half power with Modern switch

8 - Half power with Deep and Modern switches

The KPA actually showed the message saying a distorted amp has been detected even though you selected clean amp for these four so the power tubes were properly being driven

The comparison test was done by sending the Kemper Direct Out to the Input of my Triaxis. Output 1 of the Triaxis was then fed back to the Direct In of the KPA. Output 2 of the Triaxis went straight to the 2:ninety as normal.

The Trixais was set in a mono loop in Stomp D and the profile loaded in the Stack section with KPA power amp on and driving one of my Mesa EVM cabs. This was compared by A/B switching between KPA and the Triaxis direct into the 2:ninety feeding a matching Mesa EVM cab.

With the Stack section of the KPA bypassed the Triaxis sounded dull and muddy and pretty lifeless. However, when the profile of the 2:ninety power amp was engaged in the Stack section it was pretty much impossible to tell the KPA from the real thing

I'll up load all 8 profiles to RE in a moment under Wheresthedug and Mesa 2:ninety power amp.

Have fun guys.

Have fun trying them out. Adding the 2:ninety profile to the real Triaxis waowhat you would call a “subtle “ difference. It was literally like night and day. Much more dramatic than I had expected.