Hello! First timer with a question - is this used JBL cinema system worth it?

[Sentient]

Hi,

Nice to be here! The forum looks great. I have a question for you - I'm running a film sound studio... a modest one, in Eastern Europe (Romania)

I'm being offered a used JBL Cinema System, second-hand from Germany. The problem is, there are four cabinets with no label and no serial number, and the seller doesn't know what drivers are in them. Can you help me identify them, looking at the pictures?

I could really use some advice as to how to test / measure them... I have a basic SPL meter, an ECM8000 mic and did some IR measurements before.

Here are is the list and pictures.


3 DUAL SPEAKERS MODEL 4638TH

3 HORNS MODEL 2446H

4 SURROUNDS Model 8330A

7 CREST AUDIO FA 901 Amps

3 DUAL SPEAKERS - No label, no series, unknown drivers

1 SUBWOOFER - No label, no series, unknown driver

1 Monarch MODEL MHD-350


Asking price is 4000euro (4450 USD) (Negotiated down from 5000 e = 5430 USD). Do you think it's worth it?


Please note, in the pictures there were also two 4645C subs and 8x8330A's which were unfortunately sold to a music club... :(

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[Sentient]

more pics

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[grumpy]

Doesn't sound completely unreasonable if all is working.
2035H drivers are in the 4638TH.
The four cabinets look like altec drivers (3156?)
Test before buy? At least sweep within the driver's range
(JBL publishes test frequency ranges and drive voltages)

[macaroonie]

Altec it is : # 8256 cabinet part of the A6

https://www.google.co.uk/search?q=altec+lansing+8256&biw=1024&bih=650&source=lnms&tbm=isch&sa=X&ved=0ahUKEwixl6j9muPJAhVGiRoKHSc8BOIQ_AUIBygC

Based on the rest of the gear my first guess on the sub would be a 2240 in a ratty box.

68808

I think it would take you a long time and much effort to assemble that much gear and of that quality for your 4000 euro's. Most of it looks to be in good condition.

As Grumpy says , do sweeps on all the units if you can or at least get DCR readings

[JuniorJBL]

As the guys above have said looks good. I would however give pause to the Crest FA901's. I have had a few and I was never really impressed with them. Very ho-hum with lack-luster LF and HF extension.

[Sentient]

Hello,

Thank you all for your answers. I'm looking into the Altec Lansings, looks like the original horns are pretty rare, would they work with different horns? I was planning on doing an Auro3D setup with them at the top of the screen.

The amps are indeed very old, I looked into it myself, for now I'll probably get them and will likely upgrade to Crown DSI sometime in the future.

I will look into DCR readings and sweep measurements, will probably have to get the speakers outside for tests? as it is they're in a small untreated room (in storage)

The seller told me he "reconditioned" the cabinets - when I asked about that, he told me he cleaned and painted them. If he painted the horns, wouldn't that affect their performance?

Tank you all very much :)

Florian

[mech986]

The 4638's look correct, as do the horns. You need to see the horn drivers for labels, and if possible, caps/backs opened to show the diaphragms - if you're paying good euros, you want the correct JBL diaphragms, even the titaniums. If the phragms look aftermarket, considerable value is lost.

As for the other dual 15's, those look a bit like Altec cabinets too, they did build some commercial versions which were probably good cousins to the 4638 type box concept. However, important to know, with pictures, the drivers as that again determines value - if Altec or similar quality, good, if cheaper types, not so good. They don't look like the traditional vented cap Altec's, but certainly could have been reconed, or was one of the much later 70's or 80's Altec woofers which may not have had vented dustcaps. The large 18's look interesting but I have no knowledge of them.

Sorry you lost out on the 4645's though, that would have been very nice to have, probably much more musical for home purposes, somewhat wasted on a dance club.

I have no knowledge of the amps.

[badman]

Looks like a good deal, as mentioned, test for function and check out the comp drivers carefully, but that would be a very nice setup.

[Sentient]

I'm still trying to decide wether it's worth it. I now regret having written the asking price - so please try to forget it for a second - how much would you pay for this system, assuming everything works up to spec?


As for the testing - I'm making a short check list:

Apart from the obvious visual inspection, I should:
- do impendance measurments on all the drivers,
- open the backs of the speakers and check labels on the drivers,
- do exponential frequency sine sweep testing in their specified frequency ranges,
- subjective listening test - play back familiar songs...
- if possible, caps/backs opened to show the diaphragms - sorry for the newb question.. are you referring to the horns only? but how can I tell if the diaphragms are original or not?

And if they are aftermarket, from what I've seen, I can order new diaphragms straight from JBL... or maybe get Be diaphragms for them?

anything else I should keep in mind?

I don't know if the mains have a crossover installed - do I need to bring in a digital crossover (such as the behringer dcx2496) in order to test them? or can I just send a single mono signal to the amplifier, and bi-amp straight to the speakers, no crossover?

Thanks!

[rdgrimes]

Sure its worth it, if you need this gear.
A better question might be whether its suitable gear for a sound studio. Maybe yes for a larger studio/recording space. Maybe not for a mixing/mastering room

[audiomagnate]

I've been looking for a haul like that for years. If you have the room and the time/energy to unload what you don't need go it.

[Sentient]

Sure its worth it, if you need this gear.
A better question might be whether its suitable gear for a sound studio. Maybe yes for a larger studio/recording space. Maybe not for a mixing/mastering room

Why wouldn't it be suitable for a sound studio? I'm planning to use them as mains for a 7.1 dub stage currently equipped with Dynaudio BM5's + BM14S subwoofer. They are great for TV work but don't translate well to cinemas.

[audiomagnate]

Why wouldn't it be suitable for a sound studio? I'm planning to use them as mains for a 7.1 dub stage currently equipped with Dynaudio BM5's + BM14S subwoofer. They are great for TV work but don't translate well to cinemas.

Because those speakers are meant to be listened to in a real theater. You would be too close to them for the drivers to integrate properly in a typical studio setup.