Author Topic: JBL 4312A  (Read 5197 times)

Offline Sir Thrift-a-Lot

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JBL 4312A
« on: June 12, 2017, 02:20:14 PM »
I stopped at a thrift.   Nothing.   A few things that were embarrassingly overpriced.   This store is laid out in such a way that you have to circle the building to exit.   On the sidewalk in the back was a pair of 4312As.   I went back around and talked to the manager.   She said she had no way to test them.   I asked her "How much is your untested, never have to take them in the store price?"   She asked "How about $20 for the pair?"   Sure!   I can't wait to hear them.

Offline gdv

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Re: JBL 4312A
« Reply #1 on: June 12, 2017, 03:15:13 PM »
Mark,
good for you!  Hope you enjoy them, before you flip them...   ;)

George
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Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #2 on: June 12, 2017, 03:53:34 PM »
Well, my plan is to spend some time comparing them to the L100s.   So they may not end up the ones being flipped.   These appear to have the same woofer and mid, but the titanium tweeter instead of the cone.   I've liked titanium tweeters in smaller, cheaper JBLs, so I'm expecting good things here.   These also have an upgraded xover.   The L100s are slated for the mod, so I can't really compare until I get that done.   These appear to be in a smaller box (good for WAF, probably not good for bass response).   Speaking of WAF, these also have good grills.   But yes, eventually one or the other will end up going away as I have no room for a fourth system, but it likely won't be for a while.

Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #3 on: June 12, 2017, 08:01:57 PM »
The size is closer than I thought.   Same height and width, but the L100s are two inches deeper and five pounds heavier.   The plot thickens.

Offline rgpit

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Re: JBL 4312A
« Reply #4 on: June 12, 2017, 08:14:47 PM »
Wow, $20 for a pair is incredible! Nice find Mark.

Ron
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Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #5 on: June 12, 2017, 08:21:26 PM »
Thanks Ron.   They are physically in pretty good shape.   Only a couple tiny corner bumps and some water rings.   An hour with some sandpaper followed by some tung oil should have them presenting very nicely.   I haven't had a chance to evaluate the drivers, etc. yet.

Since you are the speaker guru, you may know this or know where to find out.   What settings on the mid and high pots are closest to "flat"?

Offline rgpit

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Re: JBL 4312A
« Reply #6 on: June 12, 2017, 10:20:14 PM »

....."What settings on the mid and high pots are closest to "flat"?".....

Without seeing them I really couldn't say. I checked the published specs and didn't see any recommended settings.

For me, I would choose a well recorded, natural sounding jazz or classical album. Then set the controls to minimum and adjust up until I got what I felt was the most realistic sound of the non amplified instruments. Be careful, it's easy to set them too hot.
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Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #7 on: June 12, 2017, 10:49:21 PM »
It's a funny thing.   I would prefer there not be pots on the speakers, even though I'm sure they help.   It's just one more thing to get OCD about.   I sit there wondering if the left speaker is at 6 on the scale but the right is at 6.1, even though logically I know I wouldn't be able to hear a difference.   It's a sickness of mine.   One of the things I like about the L100 xover mod is that it bypasses the pots.   Just like I prefer a quartz lock DD table to a belt.   Nothing to futz with.

Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #8 on: June 12, 2017, 11:05:28 PM »
I did find one paper that gave the sensitivity of each driver.   It lists the woofer at 89db, the mid at 94db and the tweeter at 92db, so I'm thinking that the mid will require more attenuation than the tweeter.

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Re: JBL 4312A
« Reply #9 on: June 13, 2017, 04:36:39 PM »
My guess is the middle setting on each pot should result in a flat frequency response......but that is a pure guess.  Your ears are the best guide on where to set them.

Offline Resident

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Re: JBL 4312A
« Reply #10 on: June 13, 2017, 08:07:48 PM »
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Offline RuralTom

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Re: JBL 4312A
« Reply #11 on: June 13, 2017, 09:37:02 PM »


Amen!   It's always nice to see 'em....
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Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #12 on: June 13, 2017, 10:56:25 PM »
Your wish...








Offline Sir Thrift-a-Lot

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Re: JBL 4312A
« Reply #13 on: June 13, 2017, 11:04:49 PM »
My first impression in the garage is very favorable.   They seem to do all of the right things that the L100s do but not the bad things.

I'll have to repair the one small tear, most easily seen in picture three, directly across from the big black mark.   Then they will have a date with some Barkeepers Friend, a steam iron, a sanding block and some tung oil.   After that I will get to play them in the house.

Offline EmperorNorton

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Re: JBL 4312A
« Reply #14 on: June 13, 2017, 11:29:22 PM »
They look very nice, especially for a 20.

I found some Bose 4.2 Series II speakers for .99 the other day.  Passed them on to a friend for a 20 and he was quite happy.
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