new to forum & JBL 4345

[boputnam]

I undrstand that, but they look "Brand New",and is "plush" without any sign of degradation...

Many here, with far more experience than I, eschew any woofers with foam surrounds. It is real simple - they dry out / they degrade / they dessicate. It is real obsolescence, not imagined. Think about it - those cabinets are going-on 30-yrs old. Parts need refurbishing - and not only the networks. The parts that have PHYSICAL movement have fatigued.

So I had no choice but to bi-amp them and no way to compare them to non-biamp 4345s...

I could compare, but the timing difference between going full passive and bi-amped was such that any comparision was mooted. It boiled-down to an overall appraisal. Not having heard yours, I'm guessing here, Phil, but they sound pretty astonishing bi-amped...? Same, here. No comparison.

I have nothing good to say about Klipsch loudspeakers.

OT, but never been my taste... , ,

Yeah, it irritates me to have to build the passive 4-way versions.

Now, back to those 'dreaded' 3145 mods...

[dkalsi]

I have nothing good to say about Klipsch loudspeakers.

Yeah - There are many that would agree with you. They are certainly not everyones' cup of tea. That is exactly the reason why I am dying to hear how much better the JBLs are than Klipsch. I figure I come pare one of JBLs best from the era - the JBL 4345, with one of Klipsch best from the same era - the Klipschorns.

Like I said before, I sure hope the JBLs sound better.

[Ian Mackenzie]

About 10 years ago my pre- evolution to my current 4345 clone , a 350 watt x 350 watt bi amped 4 way setup using the 2245H , an audax 8 inch mid, 2397 horn and 2405 was compared to the big K horn locally.

The bass slam of the 2245H woofer biamped with sufficiently serious horse power leaves the K horn in its wake. The passive crossover makes the 4345 waffle.

The old big K horn using to sound impressive on direct disc demos like
http://en.wikipedia.org/wiki/I%27ve_...c_in_Me_(album) but that was about it.

Every album with the 4345 baimped is a re discovery.

You need to start biamping.

Noted some K horn enthusiasts are replacing the K horn mid with dual JBL 2123s.

[pos]

Many here, with far more experience than I, eschew any woofers with foam surrounds. It is real simple - they dry out / they degrade / they dessicate.

Can foam surrounds dry out?

[tjnif]

About 10 years ago my pre- evolution to my current 4345 clone , a 350 watt x 350 watt bi amped 4 way setup using the 2245H , an audax 8 inch mid, 2397 horn and 2405 was compared to the big K horn locally.

The bass slam of the 2245H woofer biamped with sufficiently serious horse power leaves the K horn in its wake. The passive crossover makes the 4345 waffle.

The old big K horn using to sound impressive on direct disc demos like
http://en.wikipedia.org/wiki/I%27ve_...c_in_Me_(album) but that was about it.

Every album with the 4345 baimped is a re discovery.

You need to start biamping.

Noted some K horn enthusiasts are replacing the K horn mid with dual JBL 2123s.

Well I guess the verdict is not out....Cant wait to try out the Mcintosh MEN220....http://new.ecoustic.com/bbs/messages/10381/611991.html More info on the MAC unithttp://audioaficicionado.org/mcintos...-thinking.html

Re. "the old big Khorn" w/ a few mods that "Old Khorn" will be pretty impressive! Anyone who has heard my speakers are FLOORED, many have spent $10K and more And are surprised how good they sound..... But cant wait to get the jbl's up to par!

[boputnam]

Can foam surrounds dry out?

Yes, they fail over time. Great when new, but not so much after years of use or storage.

[pos]

I knew they can desintegrate with time, but not that they could dry out as lansalloy surrounds do.
I have a pair of drivers with foam surrounds that look quite hard, much harder than the brain new pair of surrounds from rick Cobbs I recently installed on a pair of 2214. I though foam surrounds could only soften with time not harden...
Time for a refoam?

[boputnam]

It's basically the same result - they lose their compliance. Lansalloy becomes brittle/hardens; "foam" surrounds don't "soften", they completely fall apart.

I remember my first discovery of this - some 7+ years ago a friend was proudly showing me his L45 Flair's at a large party at his house. I was hearing no LF output, and asked if I could remove the grills. Egads - the foam surrounds on the 130A's had completely desiccated and was laying as flakes in the grill frame.

Then, I went home and unearthed my Altec Lansing Model Nine's, which had been in storage for about 5-years.

That's how I found this place, then in it's infancy!

Time for a refoam?

Yessir! And, a recone is preferred.

[Chas]

Thanks
I am sure the JBL 4345s are in every way better, but I have yet to find it out if that improvement is worth the price difference (I really hope so).

Well as many have noted here before, the 4345's aren't plug and play. But, IMHO, they will reward you with some time, persistence and money spent. Take it slowly, one step at a time.

Once updated to as modern as possible (practical?) components, etc. the orignal design intent is still as viable today as it was in the seventies and eighties. Some may call it vintage, I don't think so. They do everything any monitor should and then some:

Wide dynamic range when bi-amped and powered appropriately
Low distortion (especially IM where the ear is very sensitive) and high SPL capability
Wide, flat frequency response
Smooth, effortless sound

What more could you ask for?

[SMKSoundPro]

A used pair of original JBL 4345 cannot be found less than $5K???

Oh YES they CAN!!! I have never divulged the purchase price for mine, because of other's jealousy or envy, but they were less...WAY less!!!

I am glad to biamp them. I don't understand why you would want the any other way? Can someone help me to understand this fullrange passive logic, please?

[4313B]

Can someone help me to understand this fullrange passive logic, please?

Some people are too scared to buy a second amp and an active filter. It's pretty complicated stuff...

[BMWCCA]

There was very little that was private about my 4345 "clone" purchase. They were offered here, at a fair price (<$4000), and I drove to hear them and picked them up for a even a bit less since I saved the seller a whole lot of trouble by helping him bring them down the curved entry stair and out into my van waiting in the snow—instead of having to ship them. Of course he did have to get his tractor to pull my van out of the front yard!

In about nine days it will have been a year since that experience. With all new components and no choice but to bi-amp them with an active crossover, I never had a chance to compare them to the completely passive stock setup.

So, what special piece of music should I play through them for our "anniversary"?


Maybe some day I'll buy an original, stock pair just for kicks!

[boputnam]

Some people are too scared to buy a second amp and an active filter. It's pretty complicated stuff...

I guess that's why more and more manufacturers are building powered speakers - bi-amped with on-board DSP's. I heard a pair of L-Acoustics' teeniest offering, their 108P. It is pretty stunning, for a toaster-oven sized cabinet, and basically plug-and-play. They've done it all for you - no extra bits (amps, crossovers, group delay, cabinet EQ) needed.

I must say that the JBL VP7212MDP is my single favorite monitor wedge. They continue to amaze me, please the artists and confound the monitor engineer! They are SO user friendly...

108P




Usable bandwidth (-10dB)

• 55 - 22k Hz

Nominal directivity (-6dB)

• 100° (± 15°) Axi-symmetric

Maximum SPL

• 125 dB ([FILL] preset)

Components

• LF: 1 x 8’’ weather-resistant transducer
• HF: 1 x 1.5’’ diaphragm compression driver

Electrical specifications

• Input stage: balanced input, max level for 0 dB setting: + 12 dBu
• DSP: 24 bit/48 kHz
• Amplifier power rating: 1 x 500 W (4 ohms - LF), 1 x 250 W (8 ohms - HF)

Physical data

• H x W x D: 421 x 250 x 299 mm - 16.6 x 9.8 x 11.8 in
• Wedge angle: 30° with regard to vertical
• Weight (net): 13 kg - 28.6 lb
• Connectors: 2 x XLR in parallel, 2 x Powercon® 120 or 230V selectable by switch
• Material: 15 mm and 18 mm Baltic birch plywood
• Finish: grayish-brown RAL 8019®
• Front: sandblast-coated steel grill, acoustically transparent ‘‘Airnet’’ black cloth
• Rigging: integrated pole mount socket, optional ETR8-2 bracket

[SMKSoundPro]

So, what special piece of music should I play through them for our "anniversary"?

"We're going have us a champagne jam" by Atlanta Rhthym Section
link: http://www.youtube.com/watch?v=1teiK...eature=related

Scotty.

[hjames]

Some people are too scared to buy a second amp and an active filter. It's pretty complicated stuff...

Pish and tush, sir ...
Not that complex - even with cheap amps improvement can be heard!

Or was that tongue firmly engaged in cheek?