JL Audio Class D amp and subs

J88TEO · March 30, 2022, 15:35

Just took the plunge and ordered the JL Audio JD400/4 series 4 Class D amp to power the JL Audio subs ( 6W3V3-4 x 2 )and Polk audio MOMO MM465.
The subs, in ported enclosures, will go behind the seats.

puma2 · March 31, 2022, 07:33

then this is done would love to see pictures

s12vea · March 31, 2022, 08:14

That will sound lovely, punchy and crisp

J88TEO · March 31, 2022, 09:31

Quote from: puma2 on March 31, 2022, 07:33 then this is done would love to see pictures

Will have pics here detailing the progress.

J88TEO · March 31, 2022, 09:32

Quote from: s12vea on March 31, 2022, 08:14That will sound lovely, punchy and crisp

Hope so...

Dev · April 2, 2022, 23:48

How many input volts are you feeding it?

J88TEO · April 3, 2022, 20:55

My HU has a pre outout voltage of 2V /10k ohms.

Dev · April 3, 2022, 21:13

Quote from: J88TEO on April 3, 2022, 20:55My HU has a pre outout voltage of 2V /10k ohms.

You should look into getting a line driver which will make those subs hit hard your components sound dyamic. The benefit with some line drivers are increase in dynamic output with higher voltage and low impedance signal where you can turn down the gains on your amp. I use to think voltage doesn't matter as long as you don't have longer runs or noisy electronics until I owned an 8 volt head unit.
Im planing to get one even though my current head unit outputs 5 volts.

J88TEO · April 3, 2022, 21:15

I didn't think about it at all. Thanks for the info. Will look into one. Any recommendation?

shnazzle · April 3, 2022, 21:21

How are you going to hear the TTE over that?

Dev · April 3, 2022, 21:38

Quote from: J88TEO on April 3, 2022, 21:15I didn't think about it at all. Thanks for the info. Will look into one. Any recommendation?

They vary in quality. Im planing on getting this one because the quality is good and they can make the system sound dynamic.
https://www.amazon.co.uk/AudioControl-Matrix-Channel-Driver-Control/dp/B01EE3YB6C

There are cheaper ones sold on EBay and I hear they are good also but who knows.

I looked at the specs of your amp and it appears that it can take up to 8 volts on the high setting so you should be good.

J88TEO · April 3, 2022, 22:05

@Dev
Thanks for the info and the link. Will look into this.
Cheers.

J88TEO · July 17, 2023, 16:46

After a long delay due to work and family commitments, my audio upgrade is completed.
Mrs 2 came with a high end old school Alpine INA-N333R head unit and I supplemented this with an old school Alipne 4 channel amp ( MRV-F340 ) and 350 mono sub amp powering Polk Audio Momo front Focal rearand 2 x JL 6W3 subs.
Tuned the amps and like the sound!...the small JLs do punch above their size!

J88TEO · July 17, 2023, 16:51

JL Audio JD400/4 series 4 Class D amp - I returned this as there were numerous reports of reliability issues!

Dev · August 6, 2023, 18:50

Quote from: J88TEO on July 17, 2023, 16:51JL Audio JD400/4 series 4 Class D amp - I returned this as there were numerous reports of reliability issues!

I was never a fan of JL amps as well as a lot of their other products and I did not comment because people get a little perturbed if I say something negative. I do run JL flagship components but they are not made by JL they are made by the same company that makes MB Quarts when they had a good reputation.

It's really hard to know what is good for the money as even Alpine is not what they use to be.

J88TEO · August 7, 2023, 14:29

I like the JL subs....that's about all. I thought of pairing these with the JD400/4 but ended up with Alpine amps of the old school class A/B types.

Dev · August 7, 2023, 14:46

Quote from: J88TEO on August 7, 2023, 14:29I like the JL subs....that's about all. I thought of pairing these with the JD400/4 but ended up with Alpine amps of the old school class A/B types.

Older amps from manufactures that had reputable names made quality amps but not so much anymore. One thing that has remained the same is the quality of the discrete electronics used in their designs and their cost adjusted for inflation which makes the older amps hold their value. Alpine along with a lot of other amps that had reputable names have switched to class D architecture for more efficiency but they are not known for sound quality even though they claim to be.

I was looking to see what is out there in the market for class D and all of them have poor SNR specs compared to AB amps but they would be great just for the fact that they can be light weight and have less load on our electrical system. The problem with buying old school is those components have a finite life just by sitting as the electrolytes dry up. It would be nice to have them serviceable by hobbyists like us.