UREI 811 monitors

[DougA]

I am toying with the thought of selling my vintage Urei 811s. I don't know what to expect as to pricing. They have grills and the "time aligned" x-overs intact.
Any info you can pass on will be appreciated.

[joyspring]

Doug,

There were four different versions of the UREI 811: the first utilised an Alnico Altec 604-8G; the second a ferrite Altec 604-8K; the third a PAS 15" coax with JBL 2425 and the final was all JBL.

The model number indicated on the crossover front panel will indicate the version number (i.e. - 828, 829, 830, etc.). Knowing this would be helpful.

Pricing depends on age (and version); the final all-JBL fetches the most (usually US$800-1200/pr.) and the original (with Altec 604-8G) the least (US$500-800/pr.).

The original usually require remagnetisation as the Alnico drivers lose quite a bit of midrange or may not `track' closely between left/right pairs, particularly after studio usage.

The rest were all-ferrite and did not suffer from monitor `drift'.

BobR

[joyspring]

Oh, and another thing: if you can afford/have the space to keep the UREIs, you ought to consider doing so.

The street price on them is definitely a lot lower than what they're worth!

BobR

[DougA]

Thanks for the reply, Bob
The model # is 829

[joyspring]

UREI 811A - Mdl. 829 Time-Aligned(tm) crossover network. Altec 604-8K (ferrite) Duplex driver with UREI 800HA horn.

I have five of these for 5.1 monitoring... not the best power response but very nice if you stay within the narrow `sweet spot' and align them `cross-eyed'. Very sharp imaging to be sure.

And with the Tangerine(tm) phasing plug + network equalisation, it is truly flat out to 16 kHz. and does not have the same problems of demagnetisation that the Alnico 604-8G/UREI 811 has.

Depending on condition, the pair should have a street value of US$650 - 850. Far lower than what they're worth...

As I mentioned earlier, if you can afford the space, you ought to keep them.

BobR

[Mirrophonic Sound System]

Hi Bob

How would you compare the sound of the various iterations of the 811's
(assuming normal magnets on the 604-8G version) ?

[joyspring]

Mirrophonic,

I'd say that the UREIs became better with each iteration and much better with the last (from 811B to 811C). This is the case with HF response and especially reducing distortion.

The final 811C was based on the JBL 2245 (info from Don McR) and has all the distortion and linearity improvements that JBL pioneered in the post-Alnico 1980s. From personal experience, it does produce audibly less distortion at high-SPL (peak) than its predecessors.

The 811B and 811C both have JBL 2425H 1"-exit compression drivers -- these do have much higher undistorted SPL and extended, flat frequency response than the Altec 604-8G and 604-8Ks used in the previous 811 and 811A.

Also, all the ferrite-magnet 811s (811A, 811B, 811C) have shorter horn throats than the Alnico 811 (Altec 604-8G) and thus mitigate this source of distortion as well.

Small-signal performance - apart from HF extension - is nearly identical with all 811s as that was UREI's intention. Voicing, EQ, directivity are nearly identical. A cursory look at the response curves of all the models bear this out.

BobR

[joyspring]

Sorry, correction in that previous post!

The JBL used as the coaxial 15" driver in the UREI 811C is the equivalent of the E145, not 2245.

BobR