I'm trying to dial-in the settings on my JL Audio MHX280/4 amp (bridged) with a DMM and 1,000 HZ test-tone playing from my iPhone through the USB connection. I had the volume on my iPhone set to 3/4.

My bike is a 2014 Limited, so I have the 6.5 Boom head unit.

In order to hit my target of 25 VAC, I need to set the volume on the headunit to 3 bars from maximum. JL recommends 23.7, but since this amp is way under-rated, I'm pushing the setting up a little, on the advice of Bagger Audio Labs.

I checked the software version for my bike and it's 1.17.1, so it's definitely an older version.

Also, I'm using the BT355 Line Levelers with low-level RCA inputs, in the default settings, as shipped from Biketronics.

Questions:

...Is using an iPhone & USB to play the test-tone a good method?

...Where do I need to set the volume on the iPhone?

...In trying to achieve the Target VAC, is 3 bars from maximum pushing the headunit too far, distortion wise?

...Should I update to another software version and try again?

I'm trying to get all my tuning ducks in a row, prior to connecting the speakers (DD-AW6.5s) and buttoning-up the fairing.

 

Still needing some help.

 

I would get a memory stick and go to the Steve Meade Designs side and download the 1k -5 test tone. Google that and it will take u right to the download site. Push repeat, then play (speaks unplugged!!!!). Phone is a good option too but the question about the volume of that device will vary. 3/4 would be my guess.

The HU will provide a clean signal with 3 bars remaining open.

I would indeed update the software. I think the last clean version that most guys are running is the 1.21.1.

Use that that dmm voltage as a target thus put a pencil mark on the gains then turn to zero before plugging in speaks. U will probably be able to get in the 26 or 27vac clean with that amp so that max might be the pencil mark u use. HPF probably will end up at 85ish.

Hope this helps!!!!

T

 

T - That helps a lot!

I need to get a USB drive/Memory stick for upgrading the Boom software, so I'll use it for the test tone as well and try again.

So, is the -5 test tone preferred over the 0?

Also, it seems that some of the software upgrades perform better than others. Is there a better (older) version than the 1.21.1 or should I stick with it?

Is there a scientific way to set the HPF or is it done by ear? I preset it at just over 80 on the dial.

 

What do you normally play music off of? That's what you should use. If it's your phone then 3/4 is fine and that's the volume you should set the music you listen to. If not use a USB stick. I would NOT set your gains with at 3 bars from max AND a -5db test tone. If you ever play max volume you will be in distortion. Either at max and -5 (that headunit from what remember will make it to max with out distorting) or 3 bars from max and 0db.

There's no scientific way to preset 80 unless you gave an SMD crossover tool.

 

The Boom 6.5 distorts at anything higher than 3 bars open, which is why I use that for my gain setting and I never exceed it.

Please confirm ur HU.

T

 

I normally listen to CD's, but I can't figure out where the loading slot is on this new fangled radio. lol

In my truck I stream music to the radio via bluetooth but using a USB cable seems to result in clearer, more detailed sound.

I'll probably put all of my music files on a USB stick and go that route on the bike.

 

Now I'm really confused.

My headunit is the factory HD 6.5 Boom.

 

See Berts post

https://www.hdforums.com/forum/audio...istortion.html

 

I stand by my comments. 3 bars open is my max on that HU.

T