Can I put woofers from pioneer cs901a into a CS-63dx pioneer speakers

QuadraphonicQuad

Help Support QuadraphonicQuad:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I would say that you should be cautious with such a swap. Although both are 8 ohm systems, they look like very different designs. The woofer crossover points are very different, and the 901a has that coaxial tweeter in the middle of the woofer. Maybe if you try disconnecting that coaxial tweeter, it may work, but the sound could still be different. Also, if you can check the pedigree of the woofer that is in the 63dx, you may find that Pioneer used the same driver without the funky tweeter.

Crossover points:
CS901a: 1700, 6000, 9000Hz
CS63dx: 770, 3300, 12000Hz

You can give it a try anyway.

Finally, like LuvMyQuad said, please be more direct with your titles . This is not a porn site. 🤣
 
I used to know a speaker manufacturer. There are a LOT of variables that go into speaker box design. Some of them are:

Speaker diameter and open air response.
Speaker complement.
Box dimensions and volume.
Speaker compliance (whether it can be used in a bass-reflex box or requires a sealed box).
Port dimensions (bass reflex).
Path length port to speaker.
Crossover design and frequencies.
 
Assuming that the drivers are the same physical size a qualified yes. The speakers should however be matched for impedance, or the crossover will be messed up. They should also be of similar power handling ability and efficiency.

I've often repaired speakers for people by replacing blown drivers with replacements that were dissimilar to the originals , often with better results than stock (assuming that the replacements are better quality than the originals).

Speakers are the most subjective part of an audio system, don't get too hung up on details. If it sounds good to you, it is good.

The woofer in the CS901a woofer is crossed over at a higher frequency than that of the CS63dx so it should be OK to cross it over at the lower frequency. Without knowing anything else about those speakers my response is pure speculation.

You don't say if you are cannibalizing one set of speakers to repair the other or if you have access to those other woofers as replacements.
 
Assuming that the drivers are the same physical size a qualified yes. The speakers should however be matched for impedance, or the crossover will be messed up. They should also be of similar power handling ability and efficiency.

I've often repaired speakers for people by replacing blown drivers with replacements that were dissimilar to the originals , often with better results than stock (assuming that the replacements are better quality than the originals).

Speakers are the most subjective part of an audio system, don't get too hung up on details. If it sounds good to you, it is good.

The woofer in the CS901a woofer is crossed over at a higher frequency than that of the CS63dx so it should be OK to cross it over at the lower frequency. Without knowing anything else about those speakers my response is pure speculation.

You don't say if you are cannibalizing one set of speakers to repair the other or if you have access to those other woofers as replacements.
But what about that super tweeter sticking out of the center of the CS901a woofer? That seems like a definite complication.
 
yep, it looks to be a coaxial driver. also, the drivers frame seems to be unusually shaped with 6 mounting lugs protruding. Thats not to say it couldnt be adapted to fit though, and, as above, the compression driver mounted on the rear can be left disconnected.

As for how it'll sound - who knows - probably different but as to whether thats a difference thats acceptable (or maybe, if youre lucky, preferable) or not, the only real answer is to try it
 
I would suggest doing a search for Pioneer PW-382A which is the correct woofer part number rather than sub'ing parts. There are some on ebay.

They aren't cheap though, even in 1981!
pioneerpricepw.jpg
 
Last edited:
I agree with keeping drivers original if possible. Years ago I was told to put different woofers in Advent speakers. It did not sound as good as the old drivers. We used to pitch the old ones and all they needed were foam surrounds. That was unfortunate.
 
I agree with keeping drivers original if possible. Years ago I was told to put different woofers in Advent speakers. It did not sound as good as the old drivers. We used to pitch the old ones and all they needed were foam surrounds. That was unfortunate.
I did that with some Baby Advents, except I replaced the tweeters because I blew one in the pair. Completely screwed up the sound quality.

I had already done the foam surrounds in those a few years before.

Noticed on ebay one of the woofers in question pretty reasonably priced and about 10 miles from my house. If I needed one...☺
 
Last edited:
I agree with keeping drivers original if possible. Years ago I was told to put different woofers in Advent speakers. It did not sound as good as the old drivers. We used to pitch the old ones and all they needed were foam surrounds. That was unfortunate.
We haven't heard back from the original poster but yes if the surrounds have rotted out he could simply befoam them!
 
Refoaming can also alter the sound compared to the original foam and also to what it deteriorated to before it actually crumbled.

Cosmetically nice and solidly built old boxes are a great opportunity to upgrade. There are a lot more drivers available now than there were "back in the day".

But on the Pioneer CS901a which is a four way I think I would attempt to find an example of the original and leave it all alone.
The 901 woofer if it fits ok you could remove the coax horn. I predict it would not fit the CS63dx
 
Last edited:
We haven't heard back from the original poster but yes if the surrounds have rotted out he could simply befoam them!
Except these don't have foam surrounds. Looking at the pictures on ebay. They appear to have the "doped" surrounds. Usually those don't fail.
 
Last edited:
Refoaming can also alter the sound compared to the original foam and also to what it deteriorated to before it actually crumbled.

Cosmetically nice and solidly built old boxes are a great opportunity to upgrade. There are a lot more drivers available now than there were "back in the day".
I've done 12 of the Pioneer HPM-150 40 cm woofers for myself and friends (see my avatar, X4), and if there was a sonic difference it was so slight to be imperceptible. Also I've done Advents, AR-3a's the newer '70s ones that came with foam surround woof's, and others I can't recall. No problem, and it keeps them as original as possible. YMMV!

Even did my little RadioShack Pro77s I use here on the computer. They have an oddball size woofer I couldn't find a substitute for. The foams weren't easy to find either.

optimuspro77.jpg



I'll add one other thing: I ihave a pair of Pioneer HPM-900s in the living room with the polymer graphite woofers, or DID have, until I tried to refoam them and I BROKE the first one! Damn! The PG cone is brittle and doesn't give, it cracks and snapped off in my fingers while trying to remove all of the old foam. So.. I got a pair of HPM-100 woofers, similar sensitivity, 1 Watt input and ? dB (whatever it was ) out at 1 meter on axis, and similar free-air resonance, and the cabinet volume and port size the same. That worked out great, got'em going making great sound, and I don't have to worry about those failing because they have doped cloth surrounds.

The result:
hpm900-100woof.jpg


I hope the OP shows up again!
 
Last edited:
I am not saying don't do it. I am just pointing out that one is unlikely to obtain the exact foam that was original and so various T-S parameters could shift.

I would prefer all those oldies but goodies you refoamed to a lot of new stuff.
 
Getting off topic a bit, but I like woofers with rubber surrounds. I've never had any that cracked requiring replacement. Sometimes you can even find rubber replacement kits to use to replace the rotted foam ones. I know that replacing foam with rubber would alter the sound of the woofer very significantly.

Rubber surrounds are however terrible for automotive use. They become stiff in the cold, giving poor base response.
 
Back
Top