Need Help : Noisy/crackling HF driver on solid state amp

[FredPhil]

Hello all

Sorry, I posted this first on "Guitar Amps", but it seems to fir better here.

I have a Matrix Elements FR12 cabinet which I use with My Line 6 Helix (https://usa.matrixamplification.com/fr12.html), it works with a solid-state power amp, a 12" bass driver and a 1" compression driver.

The HF compression driver is quite noisy (sort of white noise) even without any input signal and volume set at 0. I wouldn't qualify this noise as loud, but audible enough to make me feel this is not normal. I bought this cab second hand some time ago and didn't notice this before (I haven't been using this cab for a few months).

Then if I play a clean sound (so with lot of dynamics), the driver saturates even at low volume whenever I attack the strings. Helix set to line output, no eq.

Where do you think I should dig first? The compression driver itself (which seems to be ok visually; I opened it, but how should I check it more thoroughly?), or maybe the crossover filter? Or something else?

Thanks a lot for any advice.

Fred

[TomCarlos]

The HF compression driver is quite noisy ...;

Hi Fred.... What happens if you engage the DSP button? Any difference?

If during playing you can hear the compression driver working, I doubt that is the problem. But just for the heck of it, pull out the driver and tell us what you have. I would hope it is an original.

I'll see if I (or someone else) can dig up a schematic. In the meantime, here is the manual.

Matrix_Elements_fr12_fr10_manual.pdf

[FredPhil]

Hey Tom

Hi Fred.... What happens if you engage the DSP button? Any difference?

If during playing you can hear the compression driver working, I doubt that is the problem. But just for the heck of it, pull out the driver and tell us what you have. I would hope it is an original.

No change when engaging the DSP, the driver keeps crackling on dynamic playing.
The driver seems to be the original one ("Made in Italy for Matrix Amplification")...

I already have the manual but yes the schematics could help.

At least if I found out that the HF driver itself could be the cause of this behaviour, I would order one easily. But I'd like to be able to check this first.

[The Dude]

From your symptoms, I doubt it's the driver. But, if you want to check it, just unhook it from the existing amp and run another audio source to it. Just don't crank a lot of low frequency content to the driver as it's obviously not designed for that.

[FredPhil]

From your symptoms, I doubt it's the driver. But, if you want to check it, just unhook it from the existing amp and run another audio source to it. Just don't crank a lot of low frequency content to the driver as it's obviously not designed for that.

You're right, I tried it on the amp I use for my digital piano and sent some high notes to it : no problem.

[FredPhil]

Hello

OK, now I feel stupid. It seems that contrary to what's written in the manual, the output level of the Helix should not be set to max, especially when managing sound with a lot of dynamics...
The problem was that the input signal was way to high for my cab and made the HF driver saturate. By lowering the input and adapting the output I can get the right volume with the right sound, so everything is perfect.
Thanks anyway for your help, guys!
Now I must find out how to edit the title and mark it solved...

[g1]

Now I must find out how to edit the title and mark it solved...

No need and not sure if that is possible. Thank you for posting how you resolved the problem.