[Setting gain on a powered subwoofer with the DD1?]

Due to the limited space in my ride, I'm thinking of adding a powered subwoofer, not a subwoofer with an external amp, one with the amp built in. How would I go about setting the gain on it with the DD1 since you can't disconnect the speaker from the amp?

[DD1, where to put the negative lead probe, amp ground or negative speaker connection?]

I've read in here and elsewhere to put the positive to the positive speaker wire connection on the amp, which is obvious, but what about the negative? Attach it to the amp ground, or the negative speaker wire connection on the amp? My instruction manual says the negative speaker wire connection, but I've read in here to use the amps ground wire connection.

[SMD DD1 not registering head unit distortion]

Ok, I started from scratch. with a fresh battery in the DD1. My head unit's volume goes to 40. I tested at the amp, and playing the 40hz tone, the head unit distorts at 28, so I wrote down 27, then playing the 1000hz tone I can go all the way to 40. I averaged the two and used 33 as my volume to set my amp gains. The system sounds good, but I'm wondering why I get head unit distortion at 40hz and not at 1000hz? Is this something to be concerned about?

[SMD DD1 not registering head unit distortion]

On 7/14/2023 at 4:53 AM, audiofanaticz said:

Some but not all headunits will not distort at max volume when only using rca preouts.
Now if you're using the internal amp of the headunit that will usually distort long before the rca preouts will so you will want to use that as your max volume setting.

Yes, I'm using the rca preouts to a 4 channel amp, and my preout voltage is 5volts, so it will produce less noise to begin with. I'm guessing that I just set the head unit volume to the loudest I want, then use the dd1 to set the gains on the amp

[Change forum color scheme?]

Any way to change this horrible color scheme on these forums?

[SMD DD1 not registering head unit distortion]

I've tried it both ways as per the manual, and no matter what it won't register distortion even with the head unit volume all the way up. It does however register distortion of the amp no matter the head unit volume level. Any ideas?