FAQ  •  Register   •  Gallery •  Login

It is currently Wed Oct 22, 2014 7:40 pm

Carver ALS IV CROSSOVER QUESTION

<<

beemers417

User avatar

!! CarverFest Evictee !!

Posts: 1422

Joined: Tue Dec 30, 2008 3:05 pm

Location: Pittsburgh, PA

Post Wed Jul 15, 2009 12:39 pm

Carver ALS IV CROSSOVER QUESTION

Now that it is posted in the proper place, I am looking for answers.
I want to try and keep the passive crossover system if possible for the IV's.

Here is the original question with a Rabbit reply.
Thank you, this is a good start.

TNRabbit
Post subject: Re: Let's get this site back to talking about Carver


OK, here is some carver talk. \:D/ \:D/ \:D/ \:D/ =D> =D> =D> =D> =D>

Has anyone here ever modified the plat IV crossover to cut at 180 to 200Hz? Is this a good idea? Will the plat IV subs handle the frequencies to 200 well? Will it upset the balance of the sweet sound these speakers produce?
I am prepared to do the surgery to extend the longevity of the ribbons. I would also be open to a mod for a bi amp option. Pics and plans would be appreciated. I am picking up a set of Plat IV crossovers this weekend for the potential mod process. :-k :-k :-k

--Clearview actually made active xovers to specifically replace the Carver passive xovers, and if memory serves they DID cross over at 200 hz to take some pressure off the ribbons. SO, I guess the woofers would be up to handling the 200 hz signals....dunno. Maybe James can say for sure....


Also, has anyone ever modded a set of AL-III's to use a sealed sub enclosure? Any crossover changes? What driver was used? What is the volume of the cabinet?

--I've talked about & considered this, but was afraid I'd mess up the good job Bob did with them...if you were actively bi-amping & had a sinewave generator & decibel meter, you could probably make it happen. I use Infinity Perfect 10.1 (automobile apps) subs on my AL-IIIs and love them. The box volume on the AL-IIIs is APPROXIMATELY 1.8 cubic feet.


:D :D :D

THERE IS NOTHING WRONG WITH OPERA !!! I listen to it at the shop =D> I even have some on LP.--There are a couple of Operas I like to listen to....
Gunter the wonder dog is watching you...
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Wed Jul 15, 2009 1:16 pm

Re: Carver ALS IV CROSSOVER QUESTION

See my reply over where you first posted the question.
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer
<<

thuffman03

User avatar

!! CarverFest Evictee !!

Posts: 2706

Joined: Fri Sep 19, 2008 10:07 am

Location: Pittsburgh, PA

Post Wed Jul 15, 2009 1:55 pm

Re: Carver ALS IV CROSSOVER QUESTION

Here is what Bill wrote in case that other thread dies:

Beemers has a good question, and I've looked at the schematic. What I'd do is go directly to the woofers (i.e., bypass that part of the circuit, which is pretty easy), and use the existing crossover on the ribbons (which is fairly complex), and feed it only > 200Hz. I think the woofers can handle up to 200Hz, because that's where the Clearview crossed.

As for the AL-IIIs, that's a question I'd like to know the answer to, too (the interior volume of the box). Making that an acoustic suspension cabinet (you'd probably use a lot of packing foam) would be interesting.
Some cool Carver stuff!
<<

TNRabbit

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 13335

Joined: Sun Jan 14, 2007 11:53 am

Location: TN Native Languishing in VA

Post Wed Jul 15, 2009 4:54 pm

Re: Carver ALS IV CROSSOVER QUESTION

As Bob has oft said: "why don't we TRY it!?!"


:D :D :D :D :D :D :D :D :D :D :D :D
TNRabbit
Image

From FrankieD's lips to your ears: Sunfire - a quiet box of endless power.

Sunfire TG-IV/400~7 Amp
Carver SD/A-360 CDP
Benchmark DAC-1
Sony SACD/DVD-A
Active bi-amp: Ashly XR-1001 & 2 Rane PEQ-15s
Main: HotRodded AL-IIIs
Sub: Klipsch RT-12d
Center: Sunfire CRS-3c
Surround: Sunfire CRS-3 (x 2)

OconeeOrange wrote:"Gary likes to play it 'loud' as do I. His system begs you turn it up until you die"

RIP WIlliam B. Dibble, 1948-2012. I'll miss you my friend.
<<

beemers417

User avatar

!! CarverFest Evictee !!

Posts: 1422

Joined: Tue Dec 30, 2008 3:05 pm

Location: Pittsburgh, PA

Post Wed Jul 15, 2009 5:13 pm

Re: Carver ALS IV CROSSOVER QUESTION

That sounds like a good plan to me.
Gunter the wonder dog is watching you...
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Wed Jul 15, 2009 9:15 pm

Re: Carver ALS IV CROSSOVER QUESTION

If you were going to change the internals of the crossover, it's beyond my ability to do the calculations, because the crossover is odd. It's close to a Butterworth, but not really (perhaps why they call it a quasi-Butterworth. It's third order.
Platinum0001.JPG
Platinum0001.JPG (230.75 KiB) Viewed 615 times


If you were to bi-amp them, the wire marked "RED" becomes your + terminal, and the wiper on RP3 becomes your - terminal (you'd cut the wire just after L6. You can see L6, L7 and C7+C9 make a third order low pass filter, presumably passing frequencies below 150Hz (could be 100Hz) to the woofers. I tried several Butterworth calculators assuming the speaker array is 4 ohms (I think the woofers are 16 ohms apiece, all in parallel). I tried with 5R3, too, taking into account the resistance of the coils, to no avail.

As you can see, the ribbon section is quite complex, and I don't have the skill to figure it out.
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer
<<

Eddie

User avatar

Eddie The Knife

Posts: 1710

Joined: Sun May 15, 2005 7:03 pm

Location: Valhalla! Expect me when you see me!

Post Thu Jul 16, 2009 5:18 am

Re: Carver ALS IV CROSSOVER QUESTION

Bill do you have one for the original plats not the MK IV? Eddie!
Good judgment comes from experience,but experience usually comes from bad judgment.

The best thing is to learn from others that have mastered the one thing you need to learn!

I would tell you to go to hell but I already work there and I don't want to see your ugly face every day!
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Thu Jul 16, 2009 10:24 am

Re: Carver ALS IV CROSSOVER QUESTION

Yes. It's a lot simpler. The woofer crossover is a simple second order design.
Platinum.jpg
Platinum.jpg (110.96 KiB) Viewed 591 times
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer
<<

Eddie

User avatar

Eddie The Knife

Posts: 1710

Joined: Sun May 15, 2005 7:03 pm

Location: Valhalla! Expect me when you see me!

Post Fri Jul 17, 2009 5:47 pm

Re: Carver ALS IV CROSSOVER QUESTION

Thanks Bill!
Good judgment comes from experience,but experience usually comes from bad judgment.

The best thing is to learn from others that have mastered the one thing you need to learn!

I would tell you to go to hell but I already work there and I don't want to see your ugly face every day!
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Mon Jul 27, 2009 5:13 pm

Re: Carver ALS IV CROSSOVER QUESTION

I did a little more investigation of that circuit. If you replace C7 and C9, which together form a 300µF capacitor with 100µF, there is equal vlotage (almost) in the legs of the crossover at 200Hz (i.e., that's where it's crossing). The was the crossover is now set up, there is a large overlap between the ribbon and the woofers.
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer

Return to Carver Speakers

Who is online

Users browsing this forum: No registered users and 2 guests

Powered by phpBB © 2011 phpBB Group.