Need sub amp for S412P

Hi,

I've just acquired a pair of S412Ps and they're perfect except that I'm missing one sub amplifier. The previous owner told me that he was having subwoofer problems and had it checked out- the tech told him that it was an amp problem and that he needed to replace the amp. So... the old amp has gone to amp heaven (or maybe the Other Place, I don't know...), and the subwoofer is waiting patiently to be reinstalled.

I'm hoping someone here either has access to one of these amps or can refer me to a source to purchase one. I've emailed JBL but they seem uniterested in writing back.

Thanks a lot!

This like the 4th thread you've started on this same topic?
Not being rude - but we've read all 5 posts now ... they may not be readily available ... some models are more scarce than others.
Got pictures of these things?

Quote:

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Originally Posted by xsfreetime

Hi,

I've just acquired a pair of S412Ps and they're perfect except that I'm missing one sub amplifier. The previous owner told me that he was having sub-woofer problems and had it checked out- the tech told him that it was an amp problem and that he needed to replace the amp. So... the old amp has gone to amp heaven (or maybe the Other Place, I don't know...), and the sub-woofer is waiting patiently to be reinstalled.

I'm hoping someone here either has access to one of these amps or can refer me to a source to purchase one. I've emailed JBL but they seem uninterested in writing back.

Thanks a lot!

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In answer to your question this is the 3rd thread I've started. That's 2 more than I wanted or intended to start, but it wasn't clear to me where to begin so I made a misstep or two. My apologies for offending you.

Since you asked for a photo, here 'tis: http://www.amazon.com/JBL-S412P-Sing.../dp/B00002EQBP.

And here is the schematic, courtesy of Don C.:
http://audioheritage.org/vbulletin/i...attach/pdf.gifS412P STUDIO SERIES sm.pdf

Many thanks to the helpful contributors here :)

http://www.harmanaudio.com/search_br...&Parts=S412PII

This is all I could find for parts from JBL for any version of the S412. I got the earlier version with the copper colored drivers and these are gone forever from the looks of things. It seems the -2 version drivers are still available which I find comforting. The sub amp isn't even listed. You might be able to adapt one of the Parts Express Parts Express sub amps to replace it. The other choice is to see if you can cannabilize one from some place. I wish you luck!

Thanks Rusnzha. I've written to the parts people at the link you provided and I'll explore other avenues as well. Despite being a JBL devotee since my first pair of brand new 4311's I have very little technical knowledge about how they actually work, so this is a start-from-scratch learning experience for me.

I appreciate the help!

Quote:

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Originally Posted by xsfreetime

In answer to your question this is the 3rd thread I've started. That's 2 more than I wanted or intended to start, but it wasn't clear to me where to begin so I made a misstep or two. My apologies for offending you.

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just so you know, it's not a matter of offending someone...
it's just that topic crossposting in several subforums of a single website is generally considered to be poor form....


many online communities discourage this behaviour....

:cheers:

I recently bought a Dayton sub amp from Parts Express.

So far, it is a very good performer at a moderate price.

Maybe find a single JBL S412 on eBay.
I have a pair but not for sale, sorry.
I can't understand the throwing away fo an amp. I mean anything can be fixed! Heck, that guy probably kept it, repaired it and put it in the glovebox in his car ha ha.:)

Edit: Just remembered, I have service manual for that amp!

I half expect to hear from him, offering to sell me a replacement amp (at a slightly elevated price) :banghead:

Actually I'm getting one from Harman- thanks to everybody for the input!

Glad you could get 1 from Harman! When I bought my S412IIs one of the subs hummed and not because it was happy:). They sent me an RMA and shipping label and when they received my amp they shipped me a new one. The wires connecting the amp to the speakers are way small. If I dig up the service manual I'll post any info you need, just ask.

A day late but couple of these amps now on eBay from some dismantler. You're better of with the one from Harman I'm sure.:)

Just to put it in perspective - I've posted local copies of images of the JBL S412P ...
Just to have a long term reference to what's being talked about,
once the ebay auctions time out.

The original versions have the copper cones/domes, later versions (series II) are slightly different and have silver cones/domes.

I always liked the sewer grates on those ports. Kept out cats, gerbils, and rabbits, but not snakes or mice.

Heck, this is a story without an ending. xsfreetime, did you get the replacement amp installed? Tell us!

Yank

I have 2 pairs of these S412p's as well and they are great sounding speakers.
One of the woofer amps keep shutting off during high levels of bass signals.
Meaning, the bass cuts out whenever a high level of bass is sent.
The amp still functions, I just cannot increase the level without the bass cutting out. This may be a characteristic of the protection built into the unit?
I am wondering if this is the case, then perhaps the filtering caps may need changing.