Crossover advice for Altec 416a and 802d with a 32C horn.

[jeb98]

Hi,

This is my first post. It seems that the crossover forum doesn't get much traffic so I'm posting here. I have a set of Altec 416a and 802d drivers (both 16 ohm) with a 32C horn. I have them mounted in a diy 612 cabinet just because that's what I have. I am looking for advice on a crossover to use for this configuration. If there were an older Altec crossover that would work well, I would be willing to find one on ebay. Otherwise, I could make one. I already made one, that was shown on the JE labs blog (http://jelabs.blogspot.com/2014/01/altec-2-way-xo-update.html). This crossover was designed for the 414 speaker as it is crossed at 1600hz. The 416a has a frequency range of up to 1600 but I don't think this is an ideal crossover for my 416a speakers. Does anyone have a recommendation of what would work well for my setup?

Best,

Jonas

[Ed Kreamer]

Greetings Jonas from the left coast;

1600 Hz is pretty high for the 416. Altec used this horn for the 9849 studio speaker and the A-8 theater speaker. The 9849 which used the 414 LF crossed over at 1500 and the A-8 crossed over at 800. I would go for the lower crossover point, or even making it at around 1k. If I remember correctly the 416 exhibits pretty ragged response above that. The 32 does have very good horizontal dispersion up to 16k. The Altec data sheet for that horn gave the low cutoff frequency of 800 Hz. I think these speakers used the 806 driver, although the 802 will work as well. You can find some this info in the Altec section of the library on this site. Let us know what you decide and photos are always nice. Good luck and have fun.

Ed

[jeb98]

http://i1341.photobucket.com/albums/o757/Jonas_Baker/IMG_20160629_113839_zpsmtlgy2kn.jpg

Here's a bad picture of my ragged speakers. I think I could make the ports bigger as well, but I don't know what size they should be. Anyway, thank you for your reply Ed. I would have no idea how to design my own crossover, so if anyone has a schematic for a crossover that would work at a lower crossover point, such as 800hz or 1000hz, that would be great. Or, would the A8 crossover work? Perhaps could find a pair on the auction site. If anyone has any tips, pointers, etc. I would appreciate it.

Best,


Jonas

[Ed Kreamer]

Hi Jonas;

Altec xo's were 2nd order butterworth type (12dB slope) in this era. If you go on to the Parts Express site they show you how to lay one out and build one. And don't forget an L-pad otherwise the 802 will run away from your 416. Which begs the question: what are you using for an xo now? I would not use the 802 without one, even if it is a simple cap to the driver. 802's are rugged but not that rugged, and you don't want to be shopping for a new diaphram.

Hope this helps.

Ed

[gdmoore28]

Jonas,

If you do not want to design and build a crossover from scratch, you have a good choice for your combination at Parts Express. They carry an Eminence crossover, 800Hz, with 12dB slope on the woofer and 18dB on the horn. This one also has horn driver protection built in. It's in the $50 range, each. As Ed pointed out, you will still need to add an L-pad for the 802.

Of course, any off-the-shelf crossover like these will have no CD horn equalization. Even so, you can design an eq network and place it in line with the horn after the crossover.

Whether you decide to buy or build, there is an excellent resource at http://www.diyaudioandvideo.com/ This site has tutorials on building crossovers, and online programs for designing the crossovers, eq networks, zobel networks, and on and on. There is also a calculator there for determining port size.

Hope this helps.

GeeDeeEmm

[jeb98]

Thank you Ed Kramer and Gdmoore.

Thank you for the letting me know about the Eminence Crossover. I honestly don't mind building the crossover from a schematic, as it's about as far as I've learned to go with electronics so far, but I am not yet at the point where I feel comfortable designing my own crossover. I'd really rather use someone elses tried and true design, just so I know it already has an example of sounding good. I do appreciate you sending me links to the places that teach about crossovers, I will definitely read over that material to get me better acquainted with designing crossovers.

As to what I am using now, I am using the crossover shown on JE Labs blog (http://jelabs.blogspot.com/2014/01/altec-2-way-xo-update.html) (that is a link to the blog which shows the schematic I used) and it is apparently based on the 30923 Attenuator. I built it myself using paper in oil caps, and it actually sounds pretty good, I just feel that it would sound better at a lower crossover point with the 416a speakers. It does have an L-Pad for the 802d as far as I know.

Let me know if anyone knows any schematics I could use to build a crossover for these 16 ohm drivers with a lower crossover point.

Thank you so much again for all the help!

Best,

Jonas

[jamesbythebay]

Hi Jonas,

i just wanted to follow up and find out about how your Altec project was going?
Have you made any changes to the speakers?

Also, I couldn't help but notice that swell looking Gates CB-70 turntable tucked over there in the corner. Would you mind sharing your experiences with this record player? Any issues or challenges in getting it up and running?Is that a Micro-trak tonearm? Any thoughts on it?

cheers,
~james

[gdmoore28]

I don't think he's visiting the site any more.

Welcome aboard, though, James.

What kind of system are you running right now?

GeeDeeEmm

[jamesbythebay]

Thanks for your welcoming words...

Too bad about Jonas. AFAIR, he had an interesting setup...it would have been nice to hear about how it was going.

My system? In PIECES...that's the system I have right now. In fairness, I've moved since my last post, and things are still getting settled. I'm negotiating with my GF over what gets to go where. We've been pretty busy with settling in, having guests, and making other adjustments...and I've been laying low with the stereo stuff. Patience is the watchword at present.

Right now, I'm running a little light on electronics, and extra heavy on turntables. Ugh. But I love record players, and if one comes along, I'm usually rescuing it to rebuild and give to someone deserving. I have a Dual 1229 up on the bench right now. When I finish with it, I'll probably give it to my teenage daughter. But I need to find a suitable receiver to go with it. Maybe a nice Heathkit mono integrated, or a late 80's Denon DRA-1025. Different beasts, but I'll cross that bridge when I get to it.

Right now, my working turntables are a Linn LP12/Ittok/Sigma Genesis 2000MC, and a Gates CB-70 with a Gray Research 206/Denon DL-102 and a Rek-o-Kut 160 /Denon 103R. I purchased the Linn new when I was a wet behind the ears nineteen year-old submariner back in 1984. It's been a wonderful record player. My 1960's-era Gates is a crazy-great record player. It does things my 80's-era Linn only dreams about. They're both great record players...just different flavors of music.

I was using a Sherwood S-5000II until the move, but somewhere in the move, a tube socket went out on me. I haven't gotten around to replacing it yet. But...don't laugh...I have a little 6-8watt RCA Victor console control amp that's running a pair of EL84s in a single ended configuration. I'm running my Linn into that through a 90's era PS Audio MC Preamp. And out to a pair of tombstones that I threw together....

78370

...from a set of 60's-era Japanese paper drivers that were a San Francisco sidewalk find. The original speakers kind of sucked...until I put them up on a pair of double-stacked file boxes. And then they sounded really, really nice. The tombstone/Snell/Shindo cabinets sound much, much better.

I won't bore you with a laundry list of other stuff that I've got laying around. But I will cop to building an small arsenal of Altec drivers/horns. 416Z's. 414Z's, 806A's, 802D's, 811H's, 32A/B's, etc. I've been rescuing/buying them for a while now. Mainly out of curiosity. Sometimes out of respect for the objects about to be thoughtlessly discarded. But I made the mistake of hearing a fellow play his guitar through a raw (unmounted) 414z last year. He was demonstrating to me that it wasn't blown. It was stunning. Yes, he was a fabulous guitar player, with technique and insane dynamics...shooting like sparks and explosions. But...that single unmounted woofer really sang to me. It translated what he was doing, while hobbled. It gave me, as the great conjunto accordion player Steve Jordan (Hor-Daan) would say, "Chicken-skin". It was all I could do to keep my cool and not blow the ridiculously low-priced sale that hadn't yet consummated.

Anyway...(so that was a slightly overwrought way of saying that I'm about to move into a new phase of musical playback).

I think my first assault on the GF music beach head will be a supremely nice LP-based mono system. I need to come up with an Altec-based speaker system. I'll start out with the RCA EL84 amp (unless I get the Sherwood fixed first), and couple that up to the Linn. She likes the Linn.

Anyway, that's a circuitous answer to your question. If you have any suggestions re the Altecs, I'm all ears.

Cheers,
~james

[Earl K]

Missing Image:

78412


:)