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I can't find any information on the A8 speaker, specifcally, the crossover for the 32B horn. Anybody know? I might like the replace the 501-8A crossovers in my 418 8H II / 807-8A / 32B speakers. Any suggestions?
I would be agreeable to try building some from scratch if I had a detailed diagram and parts list. :)
You are crossing the 32b at 500? I can see why you want to change...Altec suggests 800 as LF limit.
Would look at the Model 19 xover. 1200 would be a lot better for that horn.
Jeff Markwart's Corner - Phase Corrected Crossovers
http://www.hostboard.com/forums/hbmc...2013/01/14.jpg
+1 to post #2.
FWIW, the "stock" network was N800F, same network found in the 846A Valencia and a few others.
I'd be tempted to use the 1221A crossover. It crosses over at 1500cps. It does have a zobel which might mess things up, but it was used with that horn.
Ok, I found this out with a quick search at Parts Express. Total parts are about $121 for each N1201-8A crossover. Some of the components aren't exactly the same value.
C1--8mfd-----------3.3+4.7-Solen
C2-16mfd---------16
C3-21mfd---------20+1
C4--6mfd-----------3+3
L1--.3mh-----------.30-14ga-Janzen
L2-2.7mh----------2.7-15ga
L3--.77ohm---------.75-15ga
R2-R4--3.9ohm----3.7-Dayton Audio DNR-10W
R5--2ohm-----------2.0ohm
R6--3ohm-----------3.0ohm
How close of a value is close enough? :)
Ya know, ABG's mention of the 1221 xover triggered that my brother offered me a pair of them for a song a couple months back. Likely still has them and would be glad to get a twenty spot for them...LMK if you wanna try that and I'll check with him.
On the subject of caps, Daytons are pretty good and dirt cheap...
Thanks for the offer OG, I will take you up on that offer. I would like to place that XO in one cabinet for a little A/B comparison. 1500 Hz sounds kind of high, but I would guess one extreme to another will be interesting.
What's a Zobel? I googled it, but understood nothing.
VH, what I'll do is check with him, if all is OK will PM you his contact info
Google "zobel network"
1221a
http://www.hostboard.com/forums/hbmc...2013/01/17.jpg
Zobels flatten the impedance of the woofer...which climb to dizzying heights as the frequency goes up. And if it doesn't stay relatively flat will throw the crossover out of whack, And prevent it from doing it's job properly. Crossover operations are based on impedance basically.
Zobel network explained in this page:
Passive Crossover Network Design
I did like this comment from the page mah posted a link to-
"In nearly all domestic systems, all film caps will be quite alright - there is no real need to insist on film and foil types unless there are very high currents involved. Metallised film caps will usually have more than sufficient current carrying ability for systems rated at up to a couple of hundred Watts, and often a lot more. Much has been made of the dielectric material, but this is generally wishful thinking, perpetuated by a fringe area of audio that insists that no reasonably priced component can ever sound any good. In many cases, you may pay the top price for polypropylene, but get polyester anyway, and few people know how to tell the difference between them."
I often see people spend incredible amounts of money on caps only to make glaring mistakes in other areas...in other words, gaining a few percent with top dog caps and losing back 20% by setting up the system badly...
If you spend more on crossover caps than your amp cost you may want to examine priorities...
It's a SYSTEM APPROACH that sounds best, many have a bunch of components that somewhat work together...and though many sound fine, could be bettered. Figure out the system's weak points and improve those FIRST...
Sorry thought it was Sunday, guess I gave the sermon early.
If I where to go to the trouble to build crossovers, it would be neat to have multiple taps with 800, 1000, and 1200Hz XO points. I think that I understand how to add caps through a juction box to get those values, but how about the inductors. And... what slope/db and everything else I have forgotten. I suppose by the end, I would have as much invested as in a good electronic XO and cheap amp for byamping, but I don't know anything. :)
there was an Altec unit with multiple corner frequencies...can't recall the model...
1285 XO... 1200, 800, 500 with switchable CD eq everyone should have a pair!Quote:
Originally Posted by Old Guy
Go for it.
altec 1285 | eBay
N1201-8A's works a charm, having used it in my A8's (clone cabinets) with 416-8B, 806-8 and 32B. Or a N1285-8 works but the 1200Hz XO freq. circuit may not be the same topology as that of the N1201 (aka M19).
Jon Archibald in Canada
I agree ! They are excellent for tweaking horns and crossover points..Makes it simple to change points by just using different taps on the network. 2 minute change over.Quote:
Originally Posted by martyh45
http://www.hostboard.com/forums/hbmc...2010/10/62.jpg
Wonder how something like these would sound?
Rolls SX45 Stereo Two-Way Mini Crossover w/Sub Output
Rolls SX45 Stereo Two-Way Mini Crossover w/Sub Output 245-1184
Active XO will give you the best results. If you have two amps you can use, then an active XO like the DCX2496 will be the cat's meow. The room placement and treatment will make a big difference and an active XO can be tweaked as you improve the room acoustics.
OTOH, if you want to go with passive for budget reasons, you really should start with some measurements of your drivers...otherwise, you're just guessing and you essentially will need luck to get a good sound.
As far as that Rolls unit - avoid it. For about the same money you can get a much better unit like the Behringer CX2310, or go for the 2496 mentioned above with all the bells and whistles.
Prolly OKQuote:
Originally Posted by VolvoHeretic
Prolly better:
Ashly SC 20 Electronic Crossover Made in USA | eBay
manual:
http://www.ashly.com/products/discon...ual%20DISC.pdf
How does the 1285 perform it's magic?
Does it have multiple additional inductors?
Or, does it have inductors with multiple taps?
2 Inductors with multiple taps... :wink2: :smile2:Quote:
Originally Posted by bowtie427ss
http://www.hostboard.com/forums/hbmc...2010/10/60.jpg
http://www.hostboard.com/forums/hbmc...2010/10/58.jpg
http://www.hostboard.com/forums/hbmc...2010/10/64.jpg
http://www.hostboard.com/forums/hbmc...2010/10/63.jpg
Sorry, for being late in responding, too much information and not enough time for research, I was busy putting wheels under my new EV Sentry IVs down in my Man Cave. If I ask nicely in a OT, will you guys answer some question regarding those? :)
Questions; Are my 501-8As 6db/octave? And what are the N1201-8A/N1285-8B - 12db/octave?
I wish they had an N12108-8Bs. :)
So, the Behringer CX2310 are 24db/octave, I have heard that I don’t want that slope. DCX2496 would be nice but budget wise is out there, and in my dream world, matched with a pair of Crown D60 or D70s and a D150S, would be my dream setup. The Ashly SC 20 would require two each?
Funny how every time I try to upgrade cheaply, it adds up to some serious $$$, just like my Volvo LOL. :)
Many thanks for posting AB! You know i love good pics.
Bowtie your welcome ! You have helped me many many times.. :cool2: