AudioAficionado.org  

Go Back   AudioAficionado.org > Audio & Video > General Speaker Discussion

General Speaker Discussion Calling all Speakers

Reply
 
Thread Tools Display Modes
  #11  
Old 09-01-2015, 12:32 AM
junker junker is offline
Guest
 
Join Date: Dec 2012
Location: Waikiki,HI | Santa Cruz, CA
Posts: 1,402
Default

Those Heathkit look really nice... the only thing I might not like is what looks like an MDF front panel. Don't those have a crossover box that can be opened? I bet if you replaced the stock 2 electrolytic caps with some nice film or oil caps I bet you would be blown away! =)



Quote:
Originally Posted by 62caddy View Post
Incidentally, I recently acquired a number of pieces of Altec literature from the late '60s to mid '70s. I'll have to post them when I get a chance.

By way of interest, I own a pair of Heathkit AS 21 speakers which utilize the same compliment as the Altec Malibu: Dual 414A 12" woofers, 806A HF driver w/811B horn.

Like the Flamenco, they're incredibly sensitive.

I had been using the AS 21s in my vintage system but have been substituted for a pair of Altec 14s which I found more to my liking. I am currently offering the Heathkits.

Last edited by junker; 09-01-2015 at 02:32 AM.
Reply With Quote
  #12  
Old 09-01-2015, 08:53 AM
62caddy's Avatar
62caddy 62caddy is offline
Member
 
Join Date: Apr 2012
Posts: 1,069
Default

Quote:
Originally Posted by junker View Post
Those Heathkit look really nice... the only thing I might not like is what looks like an MDF front panel. Don't those have a crossover box that can be opened? I bet if you replaced the stock 2 electrolytic caps with some nice film or oil caps I bet you would be blown away! =)
Thanks!

You are correct about the MDF. Fortunately it is only used on the front and rear panels; the rest is solid 1/4" plywood. Very nicely made overall.

As far as the crossover goes, there don't seem to be any caps that I can see. What do you think?
Attached Images
File Type: jpg AS 21 Crossover.jpg (80.3 KB, 82 views)
Reply With Quote
  #13  
Old 09-01-2015, 09:41 AM
JayBass JayBass is offline
Member
 
Join Date: Sep 2011
Posts: 58
Default

I left the stock crossover in place and merely disconnected all the wires from the drivers and the little plate (can't remember its technical name) that the speaker cables get connected to.
Then I used Belden hookup wire, recommended by Jabo Labs and also used by Shindo in some of their own applications, to connect these OUTBOARD crossovers to the drivers.
I ran the wire through the little opening that remained when I removed the little plate. My Auditorium 23 speaker cables then get connected to the proper places on the crossover.
Depending on which connection you choose you can fine tune the attenuation of the high frequencies to suit your room and taste. There is also a dial that can allegedly adjust the crossover point up or down from the normal 800 hertz. I have found it can make a significant difference in the sound.
All in all, the crossover cost a little over $500. Truly a bargain relative to the improvements in sound it netted me.
Reply With Quote
  #14  
Old 09-01-2015, 12:26 PM
junker junker is offline
Guest
 
Join Date: Dec 2012
Location: Waikiki,HI | Santa Cruz, CA
Posts: 1,402
Default

Yeah there are two electrolytic caps in the white cardboard box - should be a 10.5 and a 4 uF. So, if you swap them out then you will probably need to go with a 10 and 3.9uF. A lot of good options here depending on what your budget is. At the very least you could grab a multimeter and test that their values are +/-10%.

Quote:
Originally Posted by 62caddy View Post
Thanks!

You are correct about the MDF. Fortunately it is only used on the front and rear panels; the rest is solid 1/4" plywood. Very nicely made overall.

As far as the crossover goes, there don't seem to be any caps that I can see. What do you think?
Reply With Quote
  #15  
Old 09-01-2015, 12:31 PM
junker junker is offline
Guest
 
Join Date: Dec 2012
Location: Waikiki,HI | Santa Cruz, CA
Posts: 1,402
Default

So is the area where you are running the crossover into the cabinet relatively well sealed?! Mine have ~1" oval opening behind the connector plate. :/ You'd be much better off using a small piece of wood drilled with two holes to mount to the stock plate locations and then drilling a tight fitting hole to pass your Belden 9497 through. If I understand correctly... Also I can post a pic of a previous wood plate I used when I ran my crossovers external if that helps.

P.S.: I would REALLY love to hear how the speaker balance changes with x-over point...that would be super interesting!!! Are you at the stock 800Hz position then?

Quote:
Originally Posted by JayBass View Post
I left the stock crossover in place and merely disconnected all the wires from the drivers and the little plate (can't remember its technical name) that the speaker cables get connected to.
Then I used Belden hookup wire, recommended by Jabo Labs and also used by Shindo in some of their own applications, to connect these OUTBOARD crossovers to the drivers.
I ran the wire through the little opening that remained when I removed the little plate. My Auditorium 23 speaker cables then get connected to the proper places on the crossover.
Depending on which connection you choose you can fine tune the attenuation of the high frequencies to suit your room and taste. There is also a dial that can allegedly adjust the crossover point up or down from the normal 800 hertz. I have found it can make a significant difference in the sound.
All in all, the crossover cost a little over $500. Truly a bargain relative to the improvements in sound it netted me.

Last edited by junker; 09-01-2015 at 02:23 PM.
Reply With Quote
  #16  
Old 09-01-2015, 02:42 PM
62caddy's Avatar
62caddy 62caddy is offline
Member
 
Join Date: Apr 2012
Posts: 1,069
Default

Thanks Junker & JayBass. That information is very helpful.

I've often heard the crossover point of 800 Hz too low and change to 1,200 brings dramatic improvement to the 811B's performance.
Reply With Quote
  #17  
Old 09-02-2015, 08:44 PM
junker junker is offline
Guest
 
Join Date: Dec 2012
Location: Waikiki,HI | Santa Cruz, CA
Posts: 1,402
Default

Well some bad news today. I decided to head into Orange County Speaker to have the Alnico magnets re-magnetized today. Supposedly Alnico can de-mag up to about 1% per year and more if subjected to shock. So, OCS took them in the back to "test" while I was there and came back on one and said the voice coil was rubbing. I didn't hear anything when I took them out and compressed, but I have to assume the one was like that. OCS charges for re-mag'ing where Great Plains Audio includes this with a re-cone so I'm just going to send them in and expecting to be without LF drivers for a few weeks. Good news. I bet they'll sound a hell of a lot better when I get them back re-charged.

Last edited by junker; 09-02-2015 at 10:01 PM.
Reply With Quote
  #18  
Old 09-02-2015, 10:15 PM
Rick U's Avatar
Rick U Rick U is offline
Senior Member
 
Join Date: Feb 2013
Posts: 404
Default

Bummer Junker. How will a the new cone help the coil? I thought the cone referred to the paper driver. How hard would it be to find 2 drivers in good shape?
__________________
PS Audio P10, dCS Bartok, McIntosh C1100, Legacy Wavelet, McIntosh 452, Legacy Aeris
Reply With Quote
  #19  
Old 09-02-2015, 10:20 PM
junker junker is offline
Guest
 
Join Date: Dec 2012
Location: Waikiki,HI | Santa Cruz, CA
Posts: 1,402
Default

Hey Rick!

Yeah it's all one assembly - the cone, voice coil, dust cap, spider, wires, and surround. He removes the old assembly, cleans everything, installs the new assembly and applies glue and the tar goo to the surround, and check that the magnetic gap is centered and not rubbing. Bill at Great Plains Audio acquired all of the factory gear when they closed down and still services per factory, as well as sells his new current iterations. He also re-mags the Alnico to factory strength as part of the service. They will be good as they were circa 1967. They should sound killer and have more bass now.

The kit should look something like this:



Quote:
Originally Posted by Rick U View Post
Bummer Junker. How will a the new cone help the coil? I thought the cone referred to the paper driver. How hard would it be to find 2 drivers in good shape?

Last edited by junker; 09-03-2015 at 07:35 PM.
Reply With Quote
  #20  
Old 09-03-2015, 06:47 PM
Rick U's Avatar
Rick U Rick U is offline
Senior Member
 
Join Date: Feb 2013
Posts: 404
Default

Nice, you will have to break them in again.
__________________
PS Audio P10, dCS Bartok, McIntosh C1100, Legacy Wavelet, McIntosh 452, Legacy Aeris
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Audioaficionado.org tested by Norton Internet Security

All times are GMT -4. The time now is 12:13 PM.



Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
©Copyright 2009-2023 AudioAficionado.org.Privately owned, All Rights Reserved.
Audio Aficionado Sponsors
AudioAficionado Subscriber
AudioAficionado Subscriber
Inspire By Dennis Had
Inspire By Dennis Had
Harmonic Resolution Systems
Harmonic Resolution Systems
Wyred4Sound
Wyred4Sound
Dragonfire Acoustics
Dragonfire Acoustics
GIK Acoustics
GIK Acoustics
Esoteric
Esoteric
AC Infinity
AC Infinity
JL Audio
JL Audio
Add Powr
Add Powr
Accuphase - Soulution
Accuphase - Soulution
Audio by E
Audio by E
Canton
Canton
Bryston
Bryston
WireWorld Cables
WireWorld Cables
Stillpoints
Stillpoints
Bricasti Design
Bricasti Design
Furutech
Furutech
Shunyata Research
Shunyata Research
Legend Audio & Video
Legend Audio & Video