SMD Distortion Detector Question
 

Im looking for a little verification that I have done this right or advice if wrong.

I recently installed a new system on my boat and I used the DD1 to tune it.. Very simple to do and the system sounds great but feels like I am missing something.

My signal starts out a Clarion M309 head unit. Using the DD1 I found that the deck does not clip at full volume (33). Just because it doesn't feel right to me to have it at full volume, I backed it down to 30.

Next the signal goes to an arc audio ALD line driver. With the stereo at 30 I began adjusting the gain on the ALD until I got distortion (there is a clipping LED on the ALD as well and it came on at the exact time the DD1 showed distortion) I would say the gain on the ALD was a little over half at that point.

Next the signal goes to a Wetsounds 420 EQ.. Here I hooked the DD1 individually to each of the outputs on the 420and adjusted the individual volumes until I saw distortion. This point was a little over half way on the 420 volume knobs.

Finally I adjusted the gains on each of my 4 amps (Syn 4 for the boats, 2-Syn 2's (1 for each rev 410 on the tower) and 1 Syn 2 for the sub.

On each amp I started at 0 gain and adjusted up to the distortion point.

This is where it feels like I am missing something.. When adjusting the gains up on the amps I would only get barely a quarter of the way up before seeing distortion. I have set all the amp settings and crossover points per wetsounds recommendations...

Should the amp gains be that low?

The system sounds great but it feels like I am leaving something on the table..

Any advice would be appreciated.

Thanks

Not sure why you would need the line driver if you are going through the 420? That will act as a line driver and pump the signal to a 5V preout as I understand

I decided to add the line driver pretty much because of this thread.
Made some good sense.

http://www.tigeowners.com/forum/showthread.php?t=17433

In my previous system I had a small amount of hiss
I can tell you I have zero noise in my new system and probably more volume than I really need.
I just want to make sure my tuning sequence makes sense with the DD1

yes, if your amps are getting a clean high powered signal, a low gain is fine, and probably appropriate.

Thanks

What happens when you run the deck volume at like 28? Does that allow you to crank up the gains? Do you feel like it's not as loud as it used to be?
Per Tim White: (not saying you are doing anything wrong, just sharing info that may/may not be helpful in adjustments)

russ, if you are using the M309, consider running the fixed volume outputs from the deck (they are purple I think?). They sounded WAY better on my install than the variable (volume knob) outputs. The volume knob on the deck won't do anything anymore, but why do you need it to?

My DD-1 and CC-1 come in tomorrow....I'm excited

Timmy - This is a completely new system (Rev-410's, All Syn amps, 12" Sub) compared to my old System (Pro 80's (4), all Fosgate amps, and a 10" sub so its not an apples to apples comparrison. It does seem very loud and very clear. As I said above I started with everything flat and checked the head unit first with the DD1 and found no distortion point even at max volume, then I went to the Line driver, 420, and finally the amps.. I guess my main question is when I am tuning the amps, I had the head unit at 30, the line driver gain set to just below its clipping point and the 420 volume knobs set about half way (the outputs from the 420 all seemed to distort at a little over half way from there I adjusted the gains but like I said, they did not need to go up very far before distorting.
am I right to have the 420 set where I did when adjusting the amps?

Shawndoggy - That is an interesting idea and I might try that to see if there is any noticeable difference. Wouldnt you loose the ability though to control the volume via remote control say on the beach or something?

BTW, I looked up the install manual on the outputs and it says the fixed outputs are green and the non-fading outputs are purple

thanks

So the Arc line driver not only removed all the hiss, but also increase the sound volume & quality of the tower speaks? And really that's the only thing you added to the whole system at the time?

http://www.arcaudio.com/product-page...rivers/ald.asp

Yes, the remote volume wouldn't work. I never thought of that (don't use the remote that way), but it's a great point.

Green, purple, close enough! :D

I switched to the fixed outputs into my EQ and it sounded better, for sure.

I may try that to see how it sounds..

as for the remote, we spend a lot of time on the beach with the boat anchored off a little ways off shore. like to be able to control the tunes without wading out all the time. I have also been thinking about trying an RF waterproof remote out on the end of the rope for when the wife is driving.. she hates to have to deal with the stereo while driving :cool:

Like I said earlier, this is a whole new system in a new boat. In my old system I had a fusion deck to a 420 to fosgate amps to Pro 80's and I always had a small amount of hiss.

when I bought all my new equipment I included the line driver after reading about its supposed benefits to the system. When I installed everything I never did try it without the line driver I just hooked it in the chain from the start so I cant say if not having it was any different.. although now that I think about it I think I will try bypassing it just to see (and give myself piece of mind that I spent the extra $$):cool:

Russ,

If you do try it without the line driver please let me know. I recently installed a WS420 and rev 8's and I'm getting some hiss in the interior speakers and the tower.

Thanks,

Mike

Has anyone thought about putting it between the Ipod and the headunit?

The voltage on the ipods and iphones is complete crap....hence why you might not have been able to get you head unit to clip.

I am wondering if you input signal is so weak that the output on the back of the deck can not get to it's full level without clipping. So now you are having to turn up the headunit which may be causing unwanted noise.

I always liked setting my head unit pretty low - like 70% of max and using my line driver to amp up the signal. I am running Audiocontrol equipment which allows you to adjust the line voltage.

Just a point of clarification in my case.. All of the tuning I did with the DD1 was utilizing the test tone CD that came with the device.. I did not use my Ipod when checking the distortion point of the head unit.

My suggestion would be to us whatever source you use the most and tune to system to that.

If you play ipod all day - I would download the CD to your computer and upload the test tunes to your ipod.

The quality of CD playing thru the headunit versus and Ipod playing into the headunit is going to be very different.

Might not make a difference, but that's how I'd do and how it was suggested by the folks at SMD

Good point. I will do that.
Thanks