Swapped the TWK-88 for the Helix DSP.3 and strange things happen

[Eatmore Bacon]

So I am getting ready to have my system tuned. I had a TWK that had a remote tune that was actually good. Since swapping to the Helix I am experiencing the following after installation, less tuning.

- Minimum volume is now too loud
- both tweeters and mids have amp gains set to minimum yet still too much

Could the DSP input sensitivity need to be lowered? All speakers have time alignment measurements already entered and I zeroed everything out in the DSP as far as db gain.
I set my DSP sensitivity to be one click past the max HU volume before distortion, approx 85% of available volume dial.

Thanks

[dumdum]

I would lower the output gains (channel output levels) over the input as long as the input isn’t clipping, it just sounds like a gain structure issue instead of a problem, you likely have more signal output now

however what freq did you use to set dsp input sensitivity? Use very low freqs as that’s where distortion will creep in due to the energy distribution in music (it drops by 3db per octave just like pink noise, so 20-40hz will always clip first, 20hz being the likely contender to set it with, disconnect sub amp remote first for obvious reasons)

[Eatmore Bacon]

@dumdum It’s been so long ago I can’t remember exactly what I set it with but it was either pink noise or 2000hz if I recall. I will start there and report back. Thank you for your help.

[Chris12]

I had this same problem after installing my DSP.3 . My issue ended up being the level settings in my HU. I had previously zeroed out all the levels In my HU, but I had disconnected my battery to install the DSP.3 (can’t remember exactly why) and the factory settings have some level boosts.

If you haven’t already done so, run through your signal chain levels.

[Eatmore Bacon]

Good call, Chris. I will also check that as well. It has to be something simple.

[geolemon]

I am surprised that you are experiencing this to such an extreme that even with your amp gains set to minimum, you get too much...

...remember the good old days when 2v outputs were huge?

[Eatmore Bacon]

I am surprised as well. Once my install was complete I could faintly here a shade of distortion at very low volumes from my tweeters even with minimal gain so I knew something was up. I believe the Helix is also more powerful than the TWK. Hope to get it resolved Saturday. I will post what I find.

[Eatmore Bacon]

So I am going to get to the bottom of the issue tomorrow morning. In reviewing everything I wanted to confirm the sequence of setting up the input sensitivity properly. I know that Helix says to set it with the volume at 90% and use a 1000hz tone.

So what I did initially was found the max HU volume before clipping and then matched that volume with the input sensitivity setting utilizing a 1000hz tone. My new plan is to use a 20hz tone, per @dumdum. My question is, should I set the DSP by having the volume at max of the HU before clipping (as before), 90% of max HU before clipping, or 90% of the full spectrum of the volume dial? Just want to be clear before I begin.

[Eatmore Bacon]

So I misunderstood dumdum's post. It tests at 1000hz but he was using 20hz as an example. I guess I will start at the minimum setting and find a happy medium where my amp gains will get off of the floor and go from there. I guess one experimental way of a starting point it is to find a good minimum volume setting and go from there because, per the current setting, the DSP is not going to clip even though the amp is clipping at a lower volume.

[Eatmore Bacon]

Its done. Took a bit of going back and forth between the DSP input sensitivity and the amp gains but I have a happy medium. Tweeter and mid gains are only increase about 20% from the minimum setting. DSP level has been reduced from about 70% to about 40% from the minimum setting. I tested all channels with their specific tone with max volume before distortion. I haven't had the tune done yet but it already sounds pretty darn good.