The 4315's

[johnaec]

Here they are - just about perfect with only one or two tiny nicks that I'm sure can be rubbed out - even the bottoms are almost perfect. SN 13884A and 13891A - does the "A" signify 4315A or would it also say that on the nameplates? (They just say 4315.) One even still has a tag on the back warning against removing the bolts for the eye-hooks. 'Probably won't get them hooked up until tomorrow - I hope they sound as good as they look, and surely they'll outshine my L65A's.

John

[johnaec]

With the grilles:

[Robh3606]

WOW those are nice. Look better than most up on E-bAY!!! Don't keep us waiting too long......How do they sound????

Rob:)

[scott fitlin]

Thats about as good as it gets, congratulations!

NOW, how do they sound?

:cool:

[Guido]

You are a damned lucky guy :)

[boputnam]

Here they are - just about perfect with only one or two tiny nicks Dood!! You got HOSED!! Wow.

Oh well - kiss that $100 goodbye... :rotfl:

[scott fitlin]

Did you put any music through them yet?

[johnaec]

Did you put any music through them yet?Well, I'm actually at the office working on the network right now, so I won't have a chance to hook them up until this evening...

John

[johnaec]

OK - I finally got the 4315's connected and gave a listen, though not under ideal conditions, because I've got a band rehearsal in that room later today - :band: - positioning wasn't good. But I did do a basic A/B comparison with my L65A's.

The 4315 definitely have a "flatter" sound, I'm guessing because of the 8" mids. And the bass on the 4315's seems a little "tighter", though the L65A's actually seemed a little deeper, though just barely. I'm wondering if this might be due to the 4315's having re-surrounds that aren't really broken in, due to the nature of the music they were used for? My L65A's also have re-surrounds, but I've really cranked them since then, sometimes even using a subharmonic synthesizer!

Overall, I'm 100% happy with the 4315's! Later this week I'll rearrange the room for better placement. :)

Now - back to the question - does anyone know if the "A" in the serial numbers signify 4315"A" or did the 4315A's actually say that on the nameplates? I guess I could take a look at the crossovers to be sure... And I may have to look into the bypass capacitor option - I recall an earlier thread saying the 4315 could benefit from this.

Either way - 'probably the best money I've ever spent on a pair of speakers! :D

John

[boputnam]

...'probably the best money I've ever spent on a pair of speakers! :D Uh-oh... Now I see the problem - I had no idea you got a pair of 4315's for $100. That's entirely different... :scold:

:rotfl:

[johnaec]

Uh-oh... Now I see the problem - I had no idea you got a pair of 4315's for $100. That's entirely different... :scold:

:rotfl:Well, ya' know, if your 4345's are too big for the wifey, I'm open to a trade... :p

John

[boputnam]

Well, ya' know, if your 4345's are too big for the wifey, I'm open to a trade... :p Well, now that you say it, nuthin's too big for my wifey... :shock:

But what the heck - send me a picture of your wifey, and I'll let you know... :rotfl:

[Alex Lancaster]

:nutz: :nutz: :nutz: :D :D :D

[subwoof]

Well the "A" version used "ferrite" 12", and 5" magnet structures - These were sold right when the big alnico / ferrite conversion was changing the industry so who knows...

The only difference I see on them ( I have a pair of each version ) otherwise is a stamped "A" at the end of the serial number.

I think the "B" version had the ferrite 8" ( 2108H ) instead of the alnico 2108 - this can be found if the correct service doc's can be found ( the JBL website is lacking here )

I have a pair of 4315A that are used as rears to the 4345's and they work well but are too big for easy wall mounting.

sub

[johnaec]

But what the heck - send me a picture of your wifey, and I'll let you know... :rotfl:Now Bo - we're talking audio here...:rolleyes:

John

[johnaec]

Well the "A" version used "ferrite" 12", and 5" magnet structures - These were sold right when the big alnico / ferrite conversion was changing the industry so who knows... Hmmm - I thought I saw a scan here at one time listing the drivers in the various 4315 series that showed the A still using Alnico, but with a different crossover. I guess I'll open one up one of these days to see what's in it...

John

[Don McRitchie]

My understanding is that the original 4300 series dates from 1974 and carried no suffix (with the exception of the 4310/11 and 4320/25 which were introduced earlier). 1976 saw the introduction of the "A" series which had enclosure and network changes, but the drivers were mostly the same Alnico versions as the originals. The "B" series dates from 1979 and was introduced as a result of the ferrite driver conversion. There are likely are exceptions to this, and the 4315 may be one. However, based on the above, I would nominally expect the 4315A to contain Alnico drivers.

[mech986]

JBLPro website (www.jblpro.com (http://www.jblpro.com/)) list brochures for the 4315 and 4315B. The 4315A is not mentioned as having a marketing brochure so it may have been a short lived model. (you can find this under "product guide" then Vintage Products) - or see this link:

http://www.jblpro.com/pages/obsolete.htm

However, this page under Customer Service, Support info, Systems Reference Charts, listed under Studio Series (the 4xxx series) lists all the drivers, networks, etc. that went into building this series' speakers. The 4315 series is listed on page 2, the B model using likely redesigned networks which then had to cope with the new ferrite magnet drivers. The 4315 and 4315A had the Alnico magnet woofers.

http://www.jblproservice.com/pdf/Systems%20Reference%20Charts/Studio%20Monitor%20Series.pdf

Here's the JBL version of the schematic for the 3114 crossover of the 4315:

http://www.jblproservice.com/pdf/Network%20Schematics/3114%20Network.pdf

and here's the 3114A crossover of the 4315B:

http://www.jblproservice.com/pdf/Network%20Schematics/3114A%20Network.pdf

Hope this is of some help.

Regards,

Bart

[4313B]

The 4315A and 4315B are identical except for the alnico versus SFG ferrite drivers. Both used the 3114A network. If I remember correctly, some early versions of the 4315 with the dual ports had black baffles. I've had both the 4315A and 4315B versions. The B version is usually pretty easy to spot from a distance with the 8-inch having the terminals facing straight down and the 5-inch having the black aluminum dome.

Bypassing the capacitors is highly suggested.

[johnaec]

Thanks, Mech986 and Giskard. From that info, it looks like these are 4315A, since they have a single port and the paper dome on the 2105. I'll probably open one up anyway just to have a look-see. And in the near future I'll probably be looking for advice on bypass surgery...

Thanks again - John

[johnaec]

OK - I opened one of the 4315's today and am sure they are 4315A. LF is 2203A, and I noticed all the serial numbers, including the crossover, have the first part of the SN stamped in, with the suffix "A" screened on at the end.

I also discovered one of the clamps was hosed when I loosened it http://audioheritage.csdco.com/vbulletin/images/smilies/biting.gif - the other 7 are fine. I imagine whoever last tightened them broke the first one when he torqued it down, http://audioheritage.csdco.com/vbulletin/images/smilies/banghead.gif then did the rest correctly. See the pic in the Marketplace forum - 'anyone have a spare?

John