Yeah I read that and I get the Gain structure…maybe. The Rumble gain knob functions differently that what I'm used to. Even with the gain all the way down the Audere preamp seems to be a lot for the Rumble. I find that need to have the Audere tone controls at detent or slightly cut. Otherwise the sound gets harsh. The Audere volume is best left at 3:00 max. At first I just didn't like the sound of the Rumble 500 but was playing thru all pre amp basses. So I decided to take a step back and play thru the only stock bass I have. That's when things got settled and much better.
Every bass amp that I've owned with a Gain knob has zero input (no sound) with the knob turned all the way down. The exceptions are my mixing boards where the gain gets cut but never to the point of zero input in which case the gain acts as a variable pad. So there is a something weird about the Rumble gain which seems to act like a variable gain with a whole bunch of other stuff mixed in.
I just did an A/B comparison with my Eden WT 400 (which sounds great thru the Rumble 115 cabinet btw), the Rumble and a Yamaha MG 166cx mixing board. The Eden gain lets no signal thru when at zero while the Rumble and Yamaha do.
The Eden doesn’t care what you plug into it active or passive. My active bass tone controls accentuate the treble and bass thru the Eden while still sounding warm and musical. The passive bass tone controls do very little in comparison. However increasing the active treble control sounds less musical and harsher thru the Rumble even with the gain off. The same happens thru the mixing board via head phones or thru an amp/speaker no matter where the gain is set. The active bass control gets too bassy and looses articulation via the Rumble and mixer. Which causes me to think that the Rumble circuitry must use some similar electronics to somehow keep the cost down?
The above was done with a passive Jazz Bass and a Custom built Jazz with Barts and an Audere three band pre. To be fair I also tried my 77 Jazz with Dimarzios and a J Retro pre. It fared better. Then I tried a newer Jazz bass with an EMG JVX set up, it’s the mellow one of the active basses. That bass actually did the best of the active basses thru the Rumble. I still had to stay away from Treble and bass extremes but I always do anyway.
In the end the Eden sounded best with the J Retro and fairly good with Audere where the Rumble sounded best with the EMG or passive bass. I have for years preferred the piano string brightness I can get from the Eden with active basses. Now I have the Rumble which is different, I am not knocking it any way at this point (I know I did at first). Just like everything else it is different and I have to get acquainted to it by doing these little experiments. The Audere was new to me at that same time the Rumble was new to me. In the end I think I like the Rumble more that the Audere. So I may make some changes with that particular bass particular.
Thanks for always listening…