Very hot signal from my amp

[smokin_dave]

I was playing a music fest this afternoon and using my main rig which consist of my Crown power amp,F-1X and SF-2 Superfilter running into two Accugroove T112 8 ohm cabs.


Until recently I had been running the Crown bridged and getting the full power from it to drive the cabs.


Now I'm utilizing the SF-2 in stereo mode.Running the signal from the F-1X into channel A of the SF-2 and going from each out to channel 1 and 2 on the Crown and running the first SF-2 channel in low pass to the bottom cab and the second channel in high pass to the top cab.


Today was the first time I've used this configuration in a live setting and it just sounded phenomenal. People telling afterwards how great it sounded but for me it was like trying to hold back a runaway freight train.The signal was so hot and I was using my hands to constantly mute the strings to keep from feeding back that it became quite a headache to keep it reined in.


When I set this up at home to test it out before any live gig I didn't experience the same thing as I did today.I always plug into the #2 input jack on the F-1X and I tried pulling back on the channel gains on the Superfilter but I wasn't getting my usual overall tone control and the way I like to ultimately sound. I even dialed the dampening ratios down but it was losing what I like to really hear.


And I use a limiter that my bass goes into before it gets to the input jack on the F-1X.


I really like the sound I was achieving though and I want to keep it.Maybe dialing back the levels on the Crown may help or setting up the overall signal differently.At this point I'm open to suggestions on how to tamp down that hot signal.   

[rv_bass]

Maybe try splitting the signal coming out of the F-1X using the crossover.  Send the low pass out to channel A of the SF-2, and the high pass out to Channel B of the SF-2, then each channel out separately to the Crown amp.  Might be worth a try to see if it helps.

You might also want to try running the whole rig in mono and see if you are still getting a hot signal.  And try to isolate the problem to a specific gear component.  Maybe try a different preamp with the Crown, or plug your bass directly into the Crown to see if you are still getting a hot signal.  Or try a different power amp.

Or, try using two preamps (one for each channel) and run your bass in stereo if it’s a Series bass.

And try turning down the gain trim pots on the bass a little.

Those are my first thoughts. It will be interesting to hear what the cause is.

[smokin_dave]

Ya' know rv, I think I will use the crossover.I use my Rogue 95% of the time and have the trim pots on each pickup set at 2/3 full.I was running it in mono but it sounds so much better with the SF-2 in stereo into the cabs.


I'll mess with it this afternoon.Thanks.

[flpete1uw]

Hi Dave,
  The SF-2 has a internal jumper that changes the output level.
Maybe known, maybe helpful.
Pete

[smokin_dave]

Good point Pete.I do have the jumper set to the stock setting but I may open it up and switch it at the lowest setting.It may help out.Thanks for reminding me of that.

[mica]

The jumper is for the preamp gain function only (using the front input jack). It won't change the back panel input or outputs.

[smokin_dave]

Thanks for that info Mica.What it turned out to be was the input sensitivity on the Crown which I had switched to High when I ran it in bridged mode and had forgotten about it.Switched it back to normal mode and that seems to be the right move.

It is behaving much better now.