The next logical step from my UREI 813

[Herman Chigrin]

I'd like to ask for your thoughts on some possible directions I can take, after having used the UREI 813bx (with JBL coax) for some time now. I feel I can formulate what I like/dislike and maybe the next project will take shape (if the UREI's can't be changed to my needs).
Urei's do not have good midrange, in my opinion. It lacks clarity and has a thickness that does not blend gracefully to the highs. I can hear the tweeter being more distinct in the lower range but the woofer is letting it down by not taking over at the same resolution. Also, the lack of dynamics in the mid range is obvious. They are like a wet rag.

What I do like is the lack of comb filtering, the coherent presentation, and the consistent sweet spot and just plainly stating, a natural presentation of the sound that does not require a lot of "subconscious brain processing" to enjoy the music.

So I would like to get help in the general direction to look. Can the Ureis be made to have a better midrange? If not, I am open to going another direction, such as TAD type monitors or JBL 4722. Radian Be coaxials look interesting as well but I'm worried that may exhibit the same negatives as the UREI. The low depth is preferable in my situation. By no means are those the only options I see possible but knowing my UREIs and nothing else, they seem reasonable.

thank you all.
Herman

[Mr. Widget]

How about a pair of the JBL M2s?
I'm pretty sure these would meet all of your requirements and excel in most performance areas.


Widget

[Herman Chigrin]

Mr. Widget,
Is the 15" coax a dead end in respect to the issue I described?
I have not heard the JBL M2 nor other TAD based monitors or the JBL Cinema 2-ways. Have you compared M2 to other respectable designs? Also, the center-to-center spacing with woofer and TAD radial horns makes the MTM configuration possible. Don't know if other disadvantages outweigh this benefit, do you?

Another thought: How would a large format Be compression driver (2451 with Be diaphragm or Radian, or TAD 4003) compare to D2, soundwise?

thanks,
Herman

[1audiohack]

Hello Herman;

I ran the coax race for a while and ended up where you are. There is something I immediately recognize as right (point source) with them but sadly they leave so much on the table.

I always wanted to try my hand at building a speaker motor and thought that a JBL 2220 with a motor modified to act as the throat for a JBL 2450SL while using the curve linear cone as the rest of the horn might get it done but thats a dream I will likely never realize, heres why:

I heard a pair of Danley SH50 Synergy Horns. Talk about easy to just listen to, they do so much right. So I borrowed a pair from DSL for a couple of weeks to really give them a listen and just couldn’t let go of them, keepers for sure.

I don’t want to drift your thread to much but the only coaxial drivers I have left are a pair of Altec 604-8G’s and the only reason they will come back out of storage is for pictures for their sale.

Barry.

[grumpy]

If I ever get around to building boxes for the same JBL coax driver + (2) 2234 using a dsp for crossover (duplicating the all-pass filter to get the delays right doesn't look like fun) ... and I'll be happy to share results.

Just don't hold your breath... I'm at least 5 speaker projects deep and this one is about 3rd in the queue.

[rusty jefferson]

.....Urei's do not have good midrange, in my opinion. It lacks clarity and has a thickness that does not blend gracefully to the highs. I can hear the tweeter being more distinct in the lower range but the woofer is letting it down by not taking over at the same resolution. Also, the lack of dynamics in the mid range is obvious. They are like a wet rag....
Herman

Herman,

I realize this isn't going to help answer your question what to do with your "B" version UREIs, but of all the UREI iterations, I feel the "C" model was the best implemented. The JBL E-145 woofer used for the coax (only in the "C") is outstanding, and has none of the issues you're hearing with your "B" model, or even worse issues (imho) the "A" model suffers from. Midrange is utterly natural, clear, open and dynamic. Several members here have heard my 813C set up and would confirm this.

Still, if you want to try and improve them, I'd suggest a crossover rebuild and rewire as a start, or as Grumpy mentioned, take them active. That's potentially a fun experiment.

[Goldjazz]

How about a pair of the JBL M2s?
I'm pretty sure these would meet all of your requirements and excel in most performance areas.


Widget

Listened to a pair of M2's in a studio recently.....very nice.

[Herman Chigrin]

Thanks you for the recommendations so far.

JBL M2's: I'm trying to stay away from DSP processors. Nothing wrong with using them for mastering work but for pleasure listening -- I prefer to keep them out of the signal path.
Danley SH50: I only auditioned Danley SM96. I was disappointed with the sound quality. Their larger models would have to be a BIG step up to be considered... I mean a huge step. Is it?
Urei 813c: Is it a big step up from the 813bx? I would imagine the improvement is there but not night and day. Am I wrong?

Maybe, something like a 12" coaxial with a waveguide profile cone, a Be 1.4 compression driver sharing the same magnet and the baffle profile continuing the waveguide flare to get good loading down to 1khz of the compression driver?
Like this but scaled up, with a deeper cone+baffle profile, and a 12" coax:
https://www.genelec.com/studio-monit...studio-monitor

Just wondering about that concept. Realistically:

Has anyone compared the Elliptrack and TAD Radial and JBL Cinema horns in terms of application and sound quality? Do all need a tweeter?

[1audiohack]

I have not demo’d the SM96 so I can offer no comparison.

Tom has SH50’s in his home and told me that these would be his choice for home hifi if they were to pursue that market.

I am not trying to sell you or anyone on them, I just wondered if you had heard them.

Barry.

[Herman Chigrin]

Thanks for the tip Barry! I would love to hear the SH50’s. They may be very good indeed. I'm in Chicago and if you know of a good way to hear them please let me know. Couple of questions for you, since you know them:
Can you share any details on the crossover? I see they have a heck of a phase shift -- over 600 degrees! Although it IS linear, did you wonder about any way to flatten it? Also, does that peak around 200hz sound noticeable or strange? Do you need a sub with them?

[Robh3606]

Hello Herman

I have a liking for the C version E-145 based driver as well. I used an 811C clone as a center speaker for several years until I was able to get my hands on the Array center that replaced it. If I had not gotten the Array I would probably still be using it. That said the biggest issue I have with the Urei coax drivers is the limitations of the horns used by them. Off axis they are not that smooth and vertical directivity really makes it imperative to have them literally aimed at you primary listening position with the horns at ear level. As a center driver the placement was perfect but in a stereo pair the overall power response and off axis balance is not going to match the newer horn designs.

I think you could do better moving away from a coax design but that's just me thinking out loud

Rob

[1audiohack]

Thanks for the tip Barry! I would love to hear the SH50’s. They may be very good indeed. I'm in Chicago and if you know of a good way to hear them please let me know. Couple of questions for you, since you know them:
Can you share any details on the crossover? I see they have a heck of a phase shift -- over 600 degrees! Although it IS linear, did you wonder about any way to flatten it? Also, does that peak around 200hz sound noticeable or strange? Do you need a sub with them?

Hello Herman;

Tom is a third generation Chicagoan, until last year. Would have been easy then.

Getting a good demo, or a demo where you can just be left to it for a while is always a challenge to find. I will ask if there is anything near you.

The magnitude / phase display on the Danley site is a TEF measurment display. A very slight increase in the receive delay would flatten the phase trace all through the center and result in a phase trace with a lower displayed numerical value. It looks to me like the tracking filter is set for maximum noise immunity.

The wiggles at the 200-300Hz are where the box looses pattern control in full space due to its physical size and depth. I don’t know how much of that goes away when placed against a boundry honestly.

I need a sub with them. I have my SH50’s on four TH Mini’s per side and it is heaven. I had them on two per side and that really was adequate but four is just so solid. I run them on a pair of Crown HD5000’s, the subs have two small PEQ filters on the subs and sometimes I add a small (1.5-2dB) low Q HF boost about 16kHz, and this is music and level dependent. Other than that, no processing on the 50’s other than a high pass about 90Hz.

I really like them. They compete against some of the best speakers JBL has to offer here and hold up well. Are they the end-all of high fidelity? Of course not but I often listen to them for hours on end and they never dissapoint me.

Sorry, that’s a lot. Blah blah blah.

Barry.

[Ian Mackenzie]

My 2 cents

As good as the 813 was around 30 years ago they apparently don’t cut the mustard NOW if you read the studio forums.

So what you you using the 813 for?

Are you a looking for a 95 dB sensitivity?
What bandwidth do you need?
What’s your budget?
Do you only want to consider diy?

Have you considered the 4367 commercial offering?

On the midrange concerns it’s a problem that’s hard to eliminate in any two way

The size of the box, the size of the cones etc create compromises

A suggestion that might appeal on a modest budget is a Jbl 4435 diy clone

The 2234 woofer without the mass ring has the speed and articulation in the midrange to match the 2344/2425 horn

The biradial horn is not compromised in the way the small horn is in most coaxial designs

And the 4435 has bass

Alternatively consider using an extended bass woofer, the Jbl 2123 and the Jbl 2344 or one of the PT or newer Jbl wave guides if you have the means to evaluate different wave guides

Correctly dialed in you wont get better midrange in a diy system. (Based on readily available drivers)

I currently use the 2123 with group delay added in a modified diy Jbl 4345 4 way and the transition to the horn is absolutely seamless.

If you have an open mind look at the Earl Geddes designs or the Pi Audio designs

Attempting perfection from scratch in a forum conversation is not unusual but it’s dominated by opinion and personal preferences and may take a very long time to optimise.

My suggestion is firstly try a known design like the Jbl 4435 (diy) or the Jbl 2123 10 inch mid approach if you like the Jbl sound and go from there

Hello Herman;

Tom is a third generation Chicagoan, until last year. Would have been easy then.

Getting a good demo, or a demo where you can just be left to it for a while is always a challenge to find. I will ask if there is anything near you.

The magnitude / phase display on the Danley site is a TEF measurment display. A very slight increase in the receive delay would flatten the phase trace all through the center and result in a phase trace with a lower displayed numerical value. It looks to me like the tracking filter is set for maximum noise immunity.

The wiggles at the 200-300Hz are where the box looses pattern control in full space due to its physical size and depth. I don’t know how much of that goes away when placed against a boundry honestly.

I need a sub with them. I have my SH50’s on four TH Mini’s per side and it is heaven. I had them on two per side and that really was adequate but four is just so solid. I run them on a pair of Crown HD5000’s, the subs have two small PEQ filters on the subs and sometimes I add a small (1.5-2dB) low Q HF boost about 16kHz, and this is music and level dependent. Other than that, no processing on the 50’s other than a high pass about 90Hz.

I really like them. They compete against some of the best speakers JBL has to offer here and hold up well. Are they the end-all of high fidelity? Of course not but I often listen to them for hours on end and they never dissapoint me.

Sorry, that’s a lot. Blah blah blah.

Barry.

[grumpy]

Quote of the year candidate:

Attempting perfection from scratch in a forum conversation is not unusual but it’s dominated by opinion and personal preferences and may take a very long time to optimise.

[Herman Chigrin]

I've thought about the mentioned recommendations and, in place, decided to try the JBL 2451H on the JBL horns (were sold together). Just curious, what's the best source for the Be diaphragms, now? http://reconingspeakers.com?

Ian, The JBL 4367 as well as JBL dms-1, both interesting and I'd like to hear them. How? Any ideas on where to audition?
Why is the JBL dms-1 monitor offered in two configurations and what is the application difference, if anyone familiar with that monitor?

I will consider the Urei 811c if I can get my hands on them in Chicago. It would be interesting how the coax implementation with E145 woofer sounds. Very interesting... Anyone in Chicago with them?

Also, I will be auditioning the Danley SH50 pretty soon, so I will definitely report my findings...

Thanks, guys, for your input. Really appreciated.
Herman