Model 19 xover help (or not, you tell me)

[spwal]

Yes, the new ones look beautiful. Great work! Thank you very much for the help. I think this is a good step by step instruciton for a beginner. Though im not going to get ahead of myself until i see the speakers, just looking at the tow xovers, i think that I will probably have to be replacing mine.

You guys are super helpful, thanks!

[Gary L]

I do think you are missing a point we are trying to make SPWAL!

There is nothing at all wrong with the original stock 19 XOs. If they are working up to spec they are a good part of why the model 19 is so highly regarded as a fine vintage speaker.
As Todd White states, sure you might be able to make them better. I have heard good reports about the Iconic XOs. The ones PaulC made for me are also quite nice but I would have no reservation of leaving the original stock ones in my speakers if they sound good after the drivers are rebuilt and remagnetized at GPA. A simple thing like updating the capacitors might be all it will take to get that sweet 19 sound back after the drivers are made right.
I think if I were you, my plan would be to wait and listen when you get the speakers and if they are not broke then leave them be.
First and foremost on my list would be to have GPA check out all the drivers. If Bill says they are good to go and your speakers still don't sound right then you look into XO upgrades. If your drivers are tired and worn out or have lost their magnetism then new or updated XOs won't do a thing for you.
I hope I am explaining this right or in a way you can understand. XOs in my opinion are the last thing you do after all the other stuff is working right unless you are doing a complete restoration from the start.

Gary

[Paul C.]

The crossovers that I built for GaryL were built from the Model 19 schematic on some stripped Model 15 crossover chassis. So, I had no parts to start with. I didn't replace the original inductors... there were none on the chassis GaryL supplied, so I had to buy some new ones.

Todd White said "Also, if memory serves, to get an air-core inductor to perform the same as the iron-core's, I believe they end up being pretty large."

Yes, you can see in the photo of GaryL's I used a 2.7 mH iron core for GaryL's crossover. The 2.7 would have been HUGE if an air core, though I did use air cores for the two smaller inductors.


In the list where spwal has the prices, note that you don't need the 22 uf electrolytic AND the 20 uf and 1 uf caps. You use for cap C1 either the 22 uf (which is what I would do) electrolytic OR you would use the 20 uf poly paralleled with the 1 uf poly (to equal 21 uf) in that position.

Sonically the poly, used for the shunt cap in the woofer low pass section would be of no benefit. But the poly's could be used there for the purpose of longevity. There would be no difference in sound in that particular place in the circuit, the way that cap functions.

The caps in the high pass portion, the 8 (or 8.2), 16, and 6 (or 6.2) uf caps will benefit sonically from use of poly's.

So, cost works out using the 22 uf np elec cap for C1

2 ea 027-348 Yes 22uF-100V NON-POLARIZED CAPACITOR .. $0.75 $1.50
2 ea 027-426 Yes DAYTON DMPC-8.2 8.2uF-250V POLYPROPYLEN .. $2.75 $5.50
2 ea 027-578 Yes SOLEN 16.0uF-400VDC POLYPROPYLENE CAPAC .. $6.00 $12.00
4 ea 260-262 Yes L-PAD 100W MONO 3/8" SHAFT .. $9.25 $37.00
2 ea 027-427 Yes DAYTON DMPC-6.2 6.2uF-250V POLYPROPYLEN .. $2.15 $4.30

Subtotal: $60.30

Or using all poly's

2 ea 027-436 Yes DAYTON DMPC-20 20uF-250V POLYPROPYLENE .. $4.95 $9.90
2 ea 027-410 Yes DAYTON DMPC-1.0 1.0uF-250V POLYPROPYLEN .. $1.15 $2.30
2 ea 027-426 Yes DAYTON DMPC-8.2 8.2uF-250V POLYPROPYLEN .. $2.75 $5.50
2 ea 027-578 Yes SOLEN 16.0uF-400VDC POLYPROPYLENE CAPAC .. $6.00 $12.00
4 ea 260-262 Yes L-PAD 100W MONO 3/8" SHAFT .. $9.25 $37.00
2 ea 027-427 Yes DAYTON DMPC-6.2 6.2uF-250V POLYPROPYLEN .. $2.15 $4.30

Subtotal: $71.00

To quote GaryL "I think if I were you, my plan would be to wait and listen when you get the speakers and if they are not broke then leave them be."

Yes... If the L-pads are not noisy, don't replace them. That saves $37.00 right away. If one of the L-pads needs to be replace, the others are probably not far behind, might as well do all four while you have them apart.

Then after you get the speakers, give them a listen, and all is fine, don't fix what ain't broke. If you decide to replace the caps, which is an easy job, you or a friend could do yourself with a little soldering skill, there is the list above.

[spwal]

Thank you very much. I will go ahead and delete my list so as to avoid confusion. I will give a call now to see how best to schdule a checkup for the drivers.

thanks

Sean

[Tom Brennan]

You gotta remember that when you ask advice on a forum like this you'll be talking to some people who can never leave well enough alone and who tend to invent problems where none exist.

The best advice you got here was to listen to the speakers; use them and get used to them. Then go from there, or maybe you won't want or need to go anywhere.

I bought some 19s made in 1976 several weeks ago and I ain't a'gonna do a damned thing to them but use them.

For the time being anyway. ;-)

[John]

You gotta remember that when you ask advice on a forum like this you'll be talking to some people who can never leave well enough alone and who tend to invent problems where none exist.

The best advice you got here was to listen to the speakers; use them and get used to them. Then go from there, or maybe you won't want or need to go anywhere.

I could of not said it any better than that Tom.

[spwal]

Hi,

How come the shi shi capacitors are so much more expensive than the stuff at parts express? Also, I cant seem to find these values in, say, a auricap.

Can someone tell me which caps would be the most critical on the 19 xover?

Even better can someone link me to a place that sells these values in designer caps?

I am just curious... i want to see just how prohibitive the cost is.

Thanks!

[Paul C.]

Hi,

How come the shi shi capacitors are so much more expensive than the stuff at parts express? Also, I cant seem to find these values in, say, a auricap.

Can someone tell me which caps would be the most critical on the 19 xover?

Even better can someone link me to a place that sells these values in designer caps?

I am just curious... i want to see just how prohibitive the cost is.

Thanks!

The parts list I gave earlier is as "designer" as I get. The part numbers given are from Parts Express. www.partsexpress.com

Enter the part numbers in the search box.

[Paul C.]

As per your request,

This is what I would put in there if they were mine (Parts Express numbers)

2 ea 027-348 22uF-100V NON-POLARIZED CAPACITOR .. $0.75 $1.50
2 ea 027-426 DAYTON DMPC-8.2 8.2uF-250V POLYPROPYLEN .. $2.75 $5.50
2 ea 027-578 SOLEN 16.0uF-400VDC POLYPROPYLENE CAPAC .. $6.00 $12.00
2 ea 027-427 DAYTON DMPC-6.2 6.2uF-250V POLYPROPYLEN .. $2.15 $4.30

Total $23.30 for both speakers.

FYI, the Dayton caps from PE are Bennics and are good caps. There is absolutely nothing wrong with using a NP electolytic for C3, and nothing audible to be gained by using a poly there, but if you must:

2 ea 027-436 DAYTON DMPC-20 20uF-250V POLYPROPYLENE .. $4.95 $9.90
2 ea 027-410 DAYTON DMPC-1.0 1.0uF-250V POLYPROPYLEN .. $1.15 $2.30

(note-The 20 uf and 1 uf will be placed in parallel for 21 uf for C3)

2 ea 027-426 DAYTON DMPC-8.2 8.2uF-250V POLYPROPYLEN .. $2.75 $5.50
2 ea 027-578 SOLEN 16.0uF-400VDC POLYPROPYLENE CAPAC .. $6.00 $12.00
2 ea 027-427 DAYTON DMPC-6.2 6.2uF-250V POLYPROPYLEN .. $2.15 $4.30

Total for both speakers $34.00.

For higher grade caps in the HF circuit:

2 ea 027-436 DAYTON DMPC-20 20uF-250V POLYPROPYLENE .. $4.95 $9.90
2 ea 027-410 DAYTON DMPC-1.0 1.0uF-250V POLYPROPYLEN .. $1.15 $2.30

(note-The 20 uf and 1 uf will be placed in parallel for 21 uf for C3)

2 ea 027-692 Auricap Met Film 8 uf $32.48 ea $64.96
2 ea 027-688 Auricap Met Film 6 uf 24.38 ea 48.76
2 ea 027-578 Solen 16 uf $6.00ea $12.00

Total $137.92

I really don't think this last list is cost effective.

You asked about Jensen PIO caps... those would be in the many hundreds of dollars.

[avguytx]

Would you recommend updating the crossovers in my 846 Valencias?

What parts do I get?

Is it easy to do, or should I get someone to replace the stuff for me?

Thanks.

-Storm

Did anyone ever answer this post? I would be interested to know as well. I'm pretty sure my L-pads need replacing because they are intermittent even after cleaning and I'm sure I'm losing some upper end and just some sound in general. Seems like there are less components on the 846B's crossover, too. I have 2 caps and 2 coils. The coils look kind of weird...lol.

Any ideas?

[Paul C.]

Received Sean's crossovers this afternoon. Note the little scratch on the lower knob on the right crossover at about the 9 o'clock position.



Here is the before:



Closeup of the scratch on the faceplate:



A bad photo, but I touched it up with Birchwood Casey Aluminum Black. This is a chemical that chemically blackens aluminum. You can buy it in gun shops, or at www.brownells.com



New L-pads in both crossovers. The one on the left is recapped with Solen caps, and I've just started on the right one:



Both sides done, and I've labeled some of the components just for some later guy.



Also, I've printed and included the schematic. Note the tube of E6000 glue in the upper left corner of the first photo. All the caps were glued in place with this slightly rubbery glue. This is to prevent the components from vibrating and leads breaking, but can be cut and the components removed if necessary. I use this glue (or the equivilent, Aleene's Platinum Bond 7800) extensively when building crossovers. It is strong enough to hold heavy inductors in place. This glue should be on every electonic tech's workbench.



Dayton has these great new binding posts (Parts Express 091-1245, 091-1246, 091-1247) in gold, bright nickle plate, or satin nickle. Just drill a hole and tap them in. Secure with a lockwasher and nut. To make it more plug and play for Sean, I've already soldered the crossover input leads to the tabs. I used 14 ga oxygen free speaker wire. These are slipped over the ends of the posts, and an additional lockwasher and nut is tightened on:



Here they are, leads for input, tweeter, and woofer soldered to the crossovers. The leads have been tagged so that Sean will know what goes where. Note the crossover on the right, that scratch is invisible.



The crossovers are wrapped in bubblewrap and placed in a box with lots of plastic peanuts surrounding them, ready for Fed Ex to deliver.

No applause, no applause, and Sean already sent money.

[Hillman]

They look great Paul. Good Job!!

[spwal]

im utterly speechless.

[Charlie4350]

Talk about a happy ending.

[Storm]

I would like to "Update" my 846U crossovers.

Can anyone help me?

Where do I start? What do I do?

Thanks.

-Storm.