Model 19 xover questions?

[Tom Brennan]

Westend---Going active is fine but mind that the Nineteen crossover had EQ circuits that voiced the speaker, it was the EQ that was the heart of the 19 and made it better than previous efforts by Altec.

So if you want 19 type sound you have to figure that in.

[[email protected]]

From the Lansing Heritage forums:

http://audioheritage.org/vbulletin/s...689#post128689

Model 19 crossover slopes by Zilch and biamping info.

[westend9]

Thanks, Tom Brennan and Altec Jones.
That thread at LHF was about the clearest I've seen of an explanation of the network. The Behringer does have a CD compensation circuit built in but whether that will voice the horn to a reasonable level or be listenable is still an unanswered question for me at this point.
I did ask Zilch, on another forum, about this and he replied that part of the original network might have to be employed to get the requisite equalization.
The good news is that I don't mind building crossovers so if that is required I'm up to the task. I am not appreciating the recent copper prices and what that has done to inductor pricing. It would be a nice departure from trying to achieve bass from a backloaded horn and single driver, though, one of my recent endeavors.
I wonder if anyone has built a Model 19 network, recently, and kept record of the total price ?

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Hi westend9,

From my experience with upgraded crossovers in the Model 19s and modifying Boleros, I'd suggest staying away from Dayton capacitors and other boutique brands (Solen, Jensen PIO, Clarity, and Hovland). They didn't sound at all proper.

Some folks have tried AC motor start capacitors to supposedly good results (with Hiraga style crossover for A7s). Haven't heard them, but they would be on my short list if I was DIYing a new crossover for the 19.

Biamping with the Behringer brings the option of time aligning the acoustic outputs of the drivers. That sounds very interesting....

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Also, at this time I'm kind of leary about replacing a iron core inductor with an air core.

More than a possible change in DCR, I find that I prefered ferrite toroid core inductors to air core in the output section of a couple of 41Hz Tripath amps I've built. The ferrite core had a more substantially solid sound, whereas the air cores were more "fluffy". -Please note I am NOT an audio reviewer-

I've had air core inductors in a previous upgraded crossover for my 19s and I prefer by a wide margin the stock crossover/components.

Food for thought.

[westend9]

The PIO caps are definitely on my short list to try. I hope to have some semblance of model 19's up and running by this weekend. I still have a few cables to make.

[westend9]

Finally playing the 19's, using the Behringer CX3400. Initial impressions are somewhat clouded by the joy of finally hearing an Altec system at my house .
The Behringer does a pretty competent job. The CD compensation circuit does boost the horn in the higher frequencies. At this point, I'm happy with the choice of active. My feelings might be different if I had to buy additional amps to bi-amp. I have a few on hand that seem to handle the 19's with ease. Current setup is Kenwood Supreme 500 on the horns, JBL/UREI 6290 on the woofers.
I have plans to add Heil AMT tweeters to augment the high end. This was planned before I fired them up but first impressions are that I can do without them for awhile.
Just really digging the dynamics of this set.

[selmerdave]

FWIW I tried some AMT1's with my 604's, both as supertweeters in a 3-way and replacing the horn tweeters in a 2-way configuration. To me the character of their sound did not match the Altecs well and I much preferred the complete sound of the 604's as is, the Heil's did not last long. They are now awaiting use in another project at some point.

Dave

[westend9]

Thanks for posting your results, Dave. But, since I have them sitting on top of the cabs.... I was going to cross them over around 10 kHz or so just to see if I could add a little air to the top end. I thought I had a pair of film caps of the correct value but will have to order them. Voicing and coherency might kill this idea and I venture forth as a complete sceptic. Stranger things have proved positive in the past, however.
In actuality, the top end is not all that bad to my brass ears and I could live with them the way they are if that is the outcome. It's just cool to have a pair of speakers that are dynamic and can image a soundstage.