Model 19 HF driver

[Altec Best]

True, but I think later model 19's came with 902's. (1980-1983)

Russ

Yes I know they came with 902's later in production (very few) compared to how many with 802-8G's but he inquired about the 802d so that is why i posted that.I figured you knew that.One other thing worth mentioning is alot of the 802-8G's came with a "Lite" diaghram the 23744 which lends to it sounding very nice.Many feel this is the best sounding small format diaghram that Altec made, I have to say it is a favorite of mine too,but very fragile.Regards :2thumbsup:

[ALTECjones]

Hi Les.

As Tom noted the M19 has a passive EQ in the crossover to the 802/902 similar to the curve applied to a driver with a CD horn. It is far from flat and attenuates quite a bit below 8kHz. Search over on the Lansing Heritage forums for some of Zilch's posts and graphs on the M19 crossover. He's done ALOT of work on that.

If you are biamping and not applying the M19 EQ, adjusting the acoustic levels between the 416 and 806 to blend evenly (by ear?) the high frequencies will be MIA.

First thing to ask: are you applying the M19 EQ, either actively or passively, in your biamp scheme? If not, that's a good place to start. If you are, you might try EQing it further (pumping the HF) and fine tune the level matching between 416 and 806.

Then if you are looking for more extended clean HFs, buy a pair of TAD 2001s.

[les winter]

Yes, I am using the Model 19 shaping network in my bi-amp arrangement. Before I go experimenting with other drivers, I want to try the originals.

thanks
Les

[ALTECjones]

BTW, just joking about getting the TADs. They are spendy -but oh so good.

If you are actively EQing the 806, have you tried to boost just the HF?

[les winter]

Well, that is what the shaping network does, supresses the midrange relative to the highs. Looking Zilch's work, there just isn't enough beyond around 10k to boost.

[GM]

Couldn't he use the 806s with a 30904 eq/att with that set-up? If i happened upon a nice set of 19 cabinets, I would put the original drivers in them. But thats just me.

Based on others measurements, we're talking about at least a 22 dB loss of dynamic headroom if flattening it to ~20 kHz is desired and ~18 dB/16 kHz, so is great enough to require either a very high output impedance amp and/or an equivalent amount of CD horn EQ, potentially causing enough HF 'ringing' distortion to be distracting and even a 1.2 kHz XO point may not be high enough to keep from bottoming out the VC without a very high slope order.

Only one way to know for sure though........

GM

[voice of the theater]

Thought this might be of interest to the Model 19 fans here.....

http://www.altecpro.com/pdfs/vintage...r%20Manual.pdf

[RonSSS]

The M19 crossover, or earlier version, the N1201-8A may not be perfect, but it works well. The much criticized L-pads, work great if in good shape and not overheated. Some of the N1201-8a used in clubs etc, got cooked by too much power, I bet the HF frams were gone as well. One pair I bought, and I have a few, the Lpad wire was blue from heat.

In great shape, these crossovers allow the listener the opportunity to tweak to diff recordings. Call em tone controls or whatever, but you can tweak till you like it for a particular recording. I find them wonderful. ditto for the similar crossovers used for the duplexes from 604-K on.

Both the 802-8G and 902-8a used the same lighweight frams. I prefer the later 902-8A. Not Alnico, but just sounds better to my ears. I have both, and my -8G's are orig and never abused. I bet the 909-8A with the pascalite frams are good as well.
I have 802-8D, and the 806-8 etc, the older phase plug is inferior.
BTW, the frams are delicate, but in a home environment, you would be deaf if you drive them to blowing them up.

And I'll say this once again, remove the bug screens. The highs improve, and the left right phasey sound disappears. (move your head a foot in either direction with pink noise, and it's obvious) Ditto for removing the horn sections....which no one here in my guess has ever heard.

These driver and horns were made for theatres, where you were what, 40 to 100 feet away? Hid behind screens which dispersed the sound?

To the orig poster, either buy the new GPA stuff, I'm sure it's wonderful, or get the 802-8G, or 902-8a, remove the screens and be happy.

Do try the orig crossovers, I bet they protect the drivers better than a biamp setup.Biamp with SS amps scare me.....

But then I'm a tube guy.......

I'm a basketball Jones oh bayby oogh oh oohh

Ron

[les winter]

GPA it is. Nice folks. They responded to my email right away, and picked up the phone on the third ring.

I ordered the 902's yesterday. The curves which they emailed me show a marked difference in the upper range compared with 806a's on the the 811 horns. At 15kH, the 806a's look to be around 22dB down relative to 1.5kH. The 902 look to be 7dB down.

A bit over $400 for the pair. I'll be selling the 806a's to reduce the final cost. BTW, they manufacture 802's for a bit more. I wanted the tangerine phase plug, so I went with the 902's.

I'll be reporting back in a week or so.

thanks all.
Les

[sba2]

...remove the bug screens. The highs improve, and the left right phasey sound disappears. (move your head a foot in either direction with pink noise, and it's obvious)

Ditto for removing the horn sections....which no one here in my guess has ever heard.

Ron

I removed the sectoral fins from my 511 because they were producing a delayed ring. Sort of a difficult, messy, and very loud job though (it took about three hours with a sawzall & grinder). For home hifi, I really liked the improvement.