Walsh 2's

[ggans2 0]

Other side..

 

[BillD 239]

Well' date=' there usually aren't any electrolytic capacitors in "good" speaker crossovers.  If there are, they are non-polar, because sound is by its nature AC.  Other types of caps don't "dry out" like electrolytics.[/quote']

 

What kind of caps do you find in Plat crossovers?

I probably shouldn't have been so cavalier in my statement.  Non-polar caps are used when the capacitance gets so high that film caps become impractical.  For instance the plats have two non-polar caps in them, one which should be replaced with a film cap (150µF) and one that probably cannot (450µF).

[BillD 239]

Yeah, that picture looks different than the other one.  I wonder why one is 4µF and the other is 4.7µF?  Regardless, they should be the same.  Here is a good replacement for the 4.7µF.  And, if you want your loudspeakers to sound the same, both caps should be the same value!

You could tie a 500µF and a 250µF capacitor together in parallel together to get 750µF and a 250µF and a 125µF to get the 375µF.  All of those values are available at Parts Express too.

[ggans2 0]

Thanks Bill, The voltage on that link for the 4.7 is not 50 volts, If it has a higher voltage does that matter ? Higher is Ok but lower is not? I'm trying to learn..

 

Edit to ad, the 4uf and 4.7uf are from different pairs of walsh 2 speakers. Maybe three years apart. The crossovers look the same other than that one cap and the red ones that have Ohm printed on them..

 

Not knowing the reason why they are different does it really matter..?? hum..

[BillD 239]

Higher voltage is fine.

If I were you, I'd try to find the value that was used in the latest build and use that.

[ggans2 0]

I have sent an email to every supply company I could find on the net asking if they have these caps. So far I could not find the 75o and the 375uf.

 

I wonder what Ohm is doing, I'm not spending $350 to find out but if these caps are not avilable they must have another way because it's on there web site.. I suppose I can call them and ask..

[ggans2 0]

Could one of you in the know look here and see if they have what I need. I did find a 770uf close?

 

All the rest of the data I do not understand..

 

thanks

[BillD 239]

You didn't post a link.

[ggans2 0]

Sorry..  

 

http://www.mouser.com/Passive-Components/Capacitors/Aluminum-Electrolytic-Capacitors/Aluminum-Electrolytic-Capacitors-Leaded/_/N-75hqw/

[BillD 239]

There's nothing at Mouser or Digi-Key.  You're gonna need to look elsewhere.  Maybe Ohm can give you a pointer.

[ggans2 0]

I'll call them tomorrow, If I dont get anywhere can I match two like you said with good results?

 

 

[BillD 239]

You'll probably need an expert for that.  Electronically, yes, but sound wise, I don't know.

[ggans2 0]

Seeking hand wound custom caps.   lol just kidding.. I don't think there are any of these on the planet..

 

Question thou,  what determines the impedance of a speaker? The crossover the voice coil, both?

[ggans2 0]

Update, I called Ohm and spoke to a teck, he told me I could use two caps to get to the value I need. He also told me the caps I have now were custom made for Ohm which Is why I cant find them.

 

BTW The guy I spoke to was John, the President of Ohm Speaker...  Now on to recapping my C-2..

[BillD 239]

I'd get those NP electrolytics from Parts Express.

[ggans2 0]

Yep, that's what I am going to do.....

[BillD 239]

Did your guy say whether to use 4 or 4.7µF for that other cap.  4µF is kind of oddball.  4.7µF is a common cap.

[ggans2 0]

I asked him about that, I told him I had two pairs about three years apart and was wondering why the two had the different cap's. He did not know for sure but speculated that they must have wanted to change the sound of the speaker at some point. The walsh 2 was in production for many years.

 

I asked which he would use and he said he would pick something in the middle like a 4.3uf.. However I have not looked for one.

 

BTW The caps at parts ex are not listed as to who makes them. I was told about Bennic caps today so I looked at them also, any opinions I'm all ears..

 

Also is there a best way to combine caps?  Three 250 to get 750 instead of a 500 and a 250?

 

inquiring minds want to know..

[RichP714 3,163]

.....Question thou' date='  what determines the impedance of a speaker? The crossover the voice coil, both?
[/quote']

 

Many things determine the overall impedance of a loudspeaker.  Here is a typical impedance plot of a driver in free space

 

 

You can see the impedance varies dramatically with frequency; a static DC measurement doesn't give you the whole story.  There's a peak at driver resonance (about 50Hz) and a gradual rise with frequency.  The point somewhere in the 200-400Hz range is nearly 4 ohms; the 'rated' value of the driver.

 

Now, put this driver in a cabinet and the acoustic properties of it's evironment also contribute.  The mass and air coupling of the driver can be thought of as inductance, the suspension compliance (spider and surround) as capacitance, and frictional losses as resistance.

 

All these new additions will change the plot.

 

NOW, put a crossover in circuit, and you change the playing field again.  Capacitors and inductors will introduce phase leads and lags, changing the plot again.

 

Also, some crossover networks employ zobel networks, to compensate for the increased inductive reactance of the voice coil at higher frequencies, and they will also change the plot.

[ggans2 0]

Wow, there is a lot more to this then I ever knew, I'm still trying to figure out how these coils work. All that magnet wire, are all speakers like this..

 

I also guess that amp power measured in watts dose not mean a whole lot, more like small medium and large amp makes more sense..lol

 

 Btw One of these were recommended for the 4.7uf..

 

 

[RichP714 3,163]

.....are all speakers like this.......

Any electro-dynamic transducer will behave this way.  Electrostatics are a different paradigm, mostly capacitive reactance.

 

The voice coil windings (or trace runs in a planar type transducer) behave essentially as an inductor, so impedance climbs with frequency.

[donberry 44]

After playing around with caps, I would normally HIGHLY recommend this is the place where you want to go with the more "boutique" cap like a Dynamicap, sonicap etc, but wow, those have some really high values. I do not have a whole lot of experience with speaker caps, but I do not believe I have ever seen anything that high. It would cost a fortune just to cobble together the 47uf cap. Curious if you have a schematic to see where that 4 or 4.7 uf goes. If it is the sole cap on the mid or tweeter, might be a good place to stick in a dynamicap if you go with the 4uf (27.95 a piece), or a 4.7uf sonicap at 11.95 a piece. 

As for the inductor, again, depending on how much you love that speaker, but if you plan on keeping them around for a long time, the alpha core foil inductors are pretty nice. There is a debate whether foil is better, other one highly thought of is the Solens Perfect Lay. Depending on the value you need, it is an investment though. If it is a keeper speaker, the inductors , to my ears anyway, really do make a difference. 

While I am sire the Ohm Walsh used good ones, the place where you do cut costs a little is the inductor and caps.

I got quite a bit of flack for upgrading my Pioneer HPM-150 as many thought I should leave them stock, but collectability was not what I was looking for as I do not plan on getting rid of them. New coils and caps and while onviously not as transparent as my maggies, I am reallllly satisfied with them when they are hooked up to my main rig.

But, as mentioned, it gets pricey and is something you really only want to do if they are keepers as you would have 100+ alone in the inductors. (if I only had one choice of a more expensive upgrade, I believe I would do the inductors, tho as I only will do it on keepers, I never have to make that choice)

[BillD 239]

Unless the crossover is doing more than simply separating the frequencies (high pass, bandpass and low pass), I'd just get rid of the crossovers altogether and bi-amp or tri-amp instead of putting all that expense into a really jazzed up passive crossover.  You can get a good active crossover made (Marchand, for instance) that will even do some equalization (or you can make it yourself).

[ggans2 0]

Guys , If I can get them to sound as good as they did years ago I'll be happy..It's starting to get expensive, I spent $60 on caps for my speakers today, Just bought two Carver amps, want to recap them. I have two M400t's I want to recap also. I have a C-2 I would like to recap, if thats worth wile?

 

Reconeing two pair of speakers , I feel like there in for open heart surgey and wont survive, I'll die without them.... 

 

To boot I have my eye on this.. Maybe, 

 

http://www.bhphotovideo.com/c/product/284817-REG/ART_HQ_231_HQ231_Dual_Channel_31_Band.html

 

I would also like a CT-7 since I just discovered them, even if its MIJ...

[ggans2 0]

After playing around with caps' date=' I would normally HIGHLY recommend this is the place where you want to go with the more "boutique" cap like a Dynamicap, sonicap etc, but wow, those have some really high values. I do not have a whole lot of experience with speaker caps, but I do not believe I have ever seen anything that high. It would cost a fortune just to cobble together the 47uf cap. Curious if you have a schematic to see where that 4 or 4.7 uf goes. If it is the sole cap on the mid or tweeter, might be a good place to stick in a dynamicap if you go with the 4uf (27.95 a piece), or a 4.7uf sonicap at 11.95 a piece. 

As for the inductor, again, depending on how much you love that speaker, but if you plan on keeping them around for a long time, the alpha core foil inductors are pretty nice. There is a debate whether foil is better, other one highly thought of is the Solens Perfect Lay. Depending on the value you need, it is an investment though. If it is a keeper speaker, the inductors , to my ears anyway, really do make a difference. 

While I am sire the Ohm Walsh used good ones, the place where you do cut costs a little is the inductor and caps.

 

Wow, that is pricey stuff, is it really worth that much money?

I got quite a bit of flack for upgrading my Pioneer HPM-150 as many thought I should leave them stock, but collectability was not what I was looking for as I do not plan on getting rid of them. New coils and caps and while onviously not as transparent as my maggies, I am reallllly satisfied with them when they are hooked up to my main rig.

But, as mentioned, it gets pricey and is something you really only want to do if they are keepers as you would have 100+ alone in the inductors. (if I only had one choice of a more expensive upgrade, I believe I would do the inductors, tho as I only will do it on keepers, I never have to make that choice)

[/quote']

 

Wow Thats pricey stuff, is it really worth the money?