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Don McRitchie
06-12-2004, 09:03 PM
Well, I finally have the Model 19's that I acquired in March up and running with the correct parts. I installed the Great Plains diaphragms around a week ago and have been playing with them ever since.

As a quick recap, when I first got the speakers, neither compression driver was working since the tinsel leads had snapped on both of the diaphragms. It took nearly three months, but I finally got replacement diaphragms. In the interim, John of our forum, was kind enough to let me use a set of Symbiotic diaphragms.

With the Symbiotic diaphragms, the sound was not that good. HF was really lacking. The mids were piercing and somewhat raspy. Obviously unrelated to the diaphragms, the bass was boomy and not very extended. Fortunatey, I was able to rectify much of this with a parametric equalizer. After much playing around, I managed to get a sound quality that was at least acceptable.

When I took the speakers apart to install the new diaphragms, I decided to relocate the system. Orignally, they were in the same position as my previous primary speakers, a pair of Dahlquist DQ10's. That is to say, that they were in the corners of a 13' side wall. Since the DQ10's are notoriously bass shy, the corner reinforcement really helped their response. However, the Altecs seemed to be suffering from that positioning.

I moved the Altecs to the long wall (23') with the closest speaker to a corner being about 5' away measured from the center of the woofer. With the new diaphragms and new positioning, the speakers took on a whole new life. Bass response was no longer a one note boom. It's now apparent that the corner placement was exciting room modes in addition to gaining boundary reinforcement. The new diaphragms are much smoother through the midrange and have very good HF extension.

The mids are still too pronounced for my liking, and I find this a characteristic of every Altec horn speaker I have ever listened to. Kicking down a peak centered at around 3khz with the parametric eqaulizer does wonders for this. I find the speakers still need an extreme LF bass boost at around 40hz to counteract the natural rolloff of the woofer. With just these two tweeks, the speakers sound marvelous.

They're still not as neutral sounding as my DQ10's and they don't quite match the holographic imaging, but to my surprise, they are not that far off at all. More significantly, the Altecs have an ease of dynamics and lack of stain that the DQ10's could never hope to achieve. They are just outright toe tapping fun to listen to and this is something I have not experienced in many years.

Don McRitchie
06-12-2004, 09:04 PM
And here is a picture with the grills off:

Don McRitchie
06-12-2004, 09:05 PM
And finally, a close-up of one showing the new foam inserts around the horn that are thanks to John,

leif
06-13-2004, 06:21 AM
Looks great!:D

Alex Lancaster
06-13-2004, 10:47 AM
Don:

How would You compare them to 4430īs?

Todd W. White
06-13-2004, 05:56 PM
Hi Don,

The placement change makes great sense - you were acoustically coupling the M19's to them, ala wings on an A4, and it does mess up how the Model 19 sounds, although it helps the A4...

I have not had a problem with the horn peak you mentioned on the Mantaray horns - even the little ones - it seems more pronounced in the 811/511 series, and, as I recall, is not present in the 311 series at all, probably due to the fact that the 311's are dead as doornails when it comes to mechanical resonance. Of course, they're REALLY heavy, too...

Small amounts of eq'ing are normal and to be expected - as you know, each room behaves differently, as do each speaker system placed in it...if it needed a LOT of eq, I would be bothered...

Yes, the M19''s ARE a hoot to listen to! Live recordings (done well) sound SO REAL that you actually think you are THERE!

However - they WILL make you hate some of your recordings: if there any flaws in them, the M19's will paint the audio picture for you "warts and all."

My team is working on reintroducing a version of this speaker (we're not allowed to "reproduce" it) that is actually a clone of the improved version my old sound company built for customers who wanted them in the middle to late 1980's after Altec stopped building the Model 19's. The cabinets can be built now, as can the HF drivers and woofers, the horns are available (reconditioned - new ones are not available...yet), and the updated crossover will be available, hopefully, by end of summer. Eventually, Jerry Hubbard will have an all-new crossover for this model, available in the new systems, or as retro-fits. I'll send you a pair when we get them done...

Happy listening!

scott fitlin
06-13-2004, 06:12 PM
Yes, the M19''s ARE a hoot to listen to! Live recordings (done well) sound SO REAL that you actually think you are THERE!

However - they WILL make you hate some of your recordings: if there any flaws in them, the M19's will paint the audio picture for you "warts and all."

This happens to be the truth! Actually, the Altec, and older JBL stuff made most good recordings sound very real. The Altec horns have that " Rosin on the Bow " sound, you can hear! They do need EQ to tame a peak here and there, and Altec has a very dynamic sound to it, that makes the music very lively!

And the 19,s happen to be beautiful cabinets to have in ones living room.

:cool: