Looking for crossover mod help

[Deang]

You want to ad that 3mH inductor into the circuit don't you? We might have to. Rich is having problems getting things dialed in, and even though I had him flip polarity on the woofers he's still sensing something is off. I'm worried about that phasing issue we talked about. I was about ready to just have him bypass the low pass section in his AK-2's and then have him add the 2.5mH single inductor to his Super AA.

[rplace]

Starting to feel less informed at every turn. In searching the percyaudio catalog the only auricaps I can find in that ballpark are 12 uf and 15 uf - I don't see any 13uf. As as side anyone care to jump in here and tell me what that actually means? Anyway, looking at my old networks they say 13 uf 100v 60Hz. The 12 and 15 auricaps in the catalog say 200v with no listing of Hz values. Do you just get the closest value you can find or is there some golden rule to always go up or always go down in value if you can't find the exact match? If they were not so darned expensive I would buy some of each and experiment...unless that would actually hurt the speaker, but I need two of them and they are $28-32 each.

Along those same lines there are about a million, well ok I exaggerate, half a million [] different caps with the 2.0 uf value. There are all different brands, various ranges from 100v to 1500v and all sorts of prices. I am guessing the more you pay the better they sound, but are there any general rules in what to buy? My current ones say 2 MFD +/- 5% 230W.V.AC

Searching the archives, with very little luck I see that you might be able to put things in parallel to add up to the correct value. Should I buy a 12 and a 1 or a 10 and a 3 or some other combination to get my 13uf??? If that logic holds true why shouldn't I buy one 6 uf for each board rather then 3 of the 2.0s for each network?

I am sure you more seasoned cap dudes are getting a good laugh at this post. Go easy on the crossover virgin, will ya! [:$]

Confused, but this seems like it could be a fun but more long term project.[:^)][*-)][8-)]

[rplace]

You want to ad that 3mH inductor into the circuit don't you? We might have to. Rich is having problems getting things dialed in, and even though I had him flip polarity on the woofers he's still sensing something is off. I'm worried about that phasing issue we talked about. I was about ready to just have him bypass the low pass section in his AK-2's and then have him add the 2.5mH single inductor to his Super AA.

Dean, I am not looking to rebuild my AK-2s to replace what you built for me. I just saw them sitting in the basement gathering dust and thought if I could thorow a barrier strip on them I could go back and forth to convince myself that I am moving in the right direction. However the old AK-2s being hard wired don't lend themselves to an easy swap. You got me going on the need to replace things (caps) while I am at it.

On a completely different train of thought - I would very much like to hear your thoughts on making my DeanG Super AA for the AK series more like the Belle you built. i.e. getting rid of the stuff in the bass bin all together and putting what is necessary on the new networks.

My wife and I both noticed a major difference in our movie watching. We only use the Belle center for movies and we both independently arrived at the conclusion that since swapping out all three (khorn/belle/khorn) networks everything up front is better; that is things are clearer, seamless, smoother and the duologue now does not draw our attention to the center bottom of the screen. When I switched from a Chorus center to a Belle center I was a lot more distracted by laser sharp focus of dialog coming from "beneath" my screen. Now it is back to how it was with the chorus - anchored in the center, but not distracting. Sounds panning from center to side or side/center/side are much smoother with the current set up then ever before with old belle network or Chorus.

[tigerwoodKhorns]

Dean,

Can't be just buy a cheap paper in oil motor run 12 uF cap and bypass it with a 1.0 uF Auricap to eliminate the piercing highs that you describe? I would guess that a 200 v cap would be plenty tough enough for the job.

Chris

PS - Rick, no matter what anyone tells you (Anyone!) make sure you put a fuse in teh tweeter signal path. I just picked up a set of fuse holders at Rat Shack for my tweets as I recently tri-amped and lost teh protection in my ALK's. Cost me $1.59 for the pair. I say this because one night while playing music in a dimly lit room, the room lit up in conjunction with a loud crackle as a fuse blew when a pot on a piece of equipment passed a jolt of static electricity. The fuses cost me less than $1.00 compared to $100 for a used set of K77's had I not had the fuses.

[Deang]

Starting to feel less informed at every turn.

The more you learn the worse it gets.

In searching the percyaudio catalog the only auricaps I can find in that ballpark are 12 uf and 15 uf - I don't see any 13uf.

You're right, I guess he finally ran out of them.

As as side anyone care to jump in here and tell me what that actually means? Anyway, looking at my old networks they say 13 uf 100v 60Hz. The 12 and 15 auricaps in the catalog say 200v with no listing of Hz values. Do you just get the closest value you can find or is there some golden rule to always go up or always go down in value if you can't find the exact match?

'uF' (or mFd) is the capacitance value, '100v' is the voltage rating, and 60Hz means it's designed for motor use. You want to stay within 5% of the original capacitance value. The rule for voltage for networks is that you can use something rated higher than the original part but not lower.

Along those same lines there are about a million, well ok I exaggerate, half a million different caps with the 2.0 uf value. There are all different brands, various ranges from 100v to 1500v and all sorts of prices. I am guessing the more you pay the better they sound, but are there any general rules in what to buy? My current ones say 2 MFD +/- 5% 230W.V.AC

We just had a big discussion on the price vs. performance thing along with an examination of why or why not caps might sound different. At any rate, your original capacitors are polyester metallized film, and you get a nice lift in performance when you go to a quality metallized polypropylene or polypropylene film and foil type. The middle ground seems to be the way to go here as far as cost goes: Auricap, Kimber, Sonicap, and yes -- the GE motor runs.

Searching the archives, with very little luck I see that you might be able to put things in parallel to add up to the correct value. Should I buy a 12 and a 1 or a 10 and a 3 or some other combination to get my 13uf??? If that logic holds true why shouldn't I buy one 6 uf for each board rather then 3 of the 2.0s for each network?

Since you are going to end up paralleling -- use a 6 and 7 together to get the 13uF. The 2uF caps each handle a separate job in the circuit -- you can't use a 6 to replace them (look at the schematic).

[Deang]

Dean,

Can't be just buy a cheap paper in oil motor run 12 uF cap and bypass it with a 1.0 uF Auricap to eliminate the piercing highs that you describe? I would guess that a 200 v cap would be plenty tough enough for the job.

Chris

PS - Rick, no matter what anyone tells you (Anyone!) make sure you put a fuse in teh tweeter signal path. I just picked up a set of fuse holders at Rat Shack for my tweets as I recently tri-amped and lost teh protection in my ALK's. Cost me $1.59 for the pair. I say this because one night while playing music in a dimly lit room, the room lit up in conjunction with a loud crackle as a fuse blew when a pot on a piece of equipment passed a jolt of static electricity. The fuses cost me less than $1.00 compared to $100 for a used set of K77's had I not had the fuses.

The GE motor runs aren't 'cheap'. I mean, they cost more than Daytons or Solens, and in some values the same value costs much more. For example, the 40uF values I got from Bob ran me $18.00 each. I could have got the same value in a Solen or a Dayton for half as much. At any rate, they sound good in the Super AA. The networks I tried them in that I didn't like was the Type A and Type E. Actually I liked the sound -- as long as I didn't turn it up too loud.

All you know is that it was enough to take out a fuse -- it doesn't mean it would have taken out the tweeter.

[Deang]

Dean, I am not looking to rebuild my AK-2s to replace what you built for me. I just saw them sitting in the basement gathering dust and thought if I could thorow a barrier strip on them I could go back and forth to convince myself that I am moving in the right direction. However the old AK-2s being hard wired don't lend themselves to an easy swap. You got me going on the need to replace things (caps) while I am at it.

Give me a little bit of time and I'll draw something up that you can follow to make the rebuild less painful.

On a completely different train of thought - I would very much like to hear your thoughts on making my DeanG Super AA for the AK series more like the Belle you built. i.e. getting rid of the stuff in the bass bin all together and putting what is necessary on the new networks.

Would you believe we're only talking a single inductor here? Heck, you could screw it to the rear of the bass bin door (with the other network), disconnect the other network, wire in your inductor -- and you'd be done.

[rplace]

Would you believe we're only talking a single inductor here? Heck, you could screw it to the rear of the bass bin door (with the other network), disconnect the other network, wire in your inductor -- and you'd be done.

Is the inductor the thing on my belle network that looks like a 3 inch bar with wire wrapped around it? When I look at the two different networks that is the only thing my untrained eyes notice that are different. I took off the bass bin door to have a look and there seems to be a few things inside there and they are all big. [] Kind of cool if that one piece can replace all that mess. Now since that mess is inside the cabinet it is nice and clean...but it is still getting up there in age.

[fkjazz]

Hi,I am new in the Forum.

I am from Berlin,Germany and have a Pair of La Scala for about 30 years now,all original specification.

For better Tweeter performance I use a Pair of Plasma Tweeters-ATR Ion-Tweeter on top instead of the original.

Does it make sense to upgrade the original " historic "crossover and internal wiring to better ones. And if so,any tips for that and can I buy upgraded crossovers complete somewhere.I'm not experienced in DY any electronical components.

What about the internal wiring,any sense in using Silver cables--the original look very simple and "cheep".

Are there other Terminals available for connecting the speaker cables --to banana-plugs maybe? I am not very lucky with the original screw fixing ,doesn't fit to any modern cables.

Regards FKjazz

[Duke Spinner]

...do I need any special "audio solder"?

that innocent question, Rich ...

could stir up a hornet's nest on some boards....................[]

[Deang]

I use Kester '44'.

Does it make sense to upgrade the original " historic "crossover and internal wiring to better ones. And if so,any tips for that and can I buy upgraded crossovers complete somewhere.I'm not experienced in DY any electronical components.

What about the internal wiring,any sense in using Silver cables--the original look very simple and "cheep".

Are there other Terminals available for connecting the speaker cables --to banana-plugs maybe? I am not very lucky with the original screw fixing ,doesn't fit to any modern cables.

Regards FKjazz

At 30 years in age -- the dielectric in your capacitors is breaking down, and the resistive element is beginning to climb increasing the loss factor and robbing energy. Because of this, it's not uncommon to see tweeters running 3dB down in relationship to the squawker. It causes other problems too with the sound, and most don't realize how bad it is until they replace the networks.

You can do anything from purchase direct replacement units from Bob crites ($225 I think) to newer designs from Al Klappenburger ($430 - $1100) or myself ($345).

Your original wiring is fine -- I would leave it alone.

I offer a couple of different solutions with my networks for those who want to use cables that don't fit into the barrier strip.The solution depends on the cable used.

[fkjazz]

Thx for reply and could you be so kind to give me the links to the websides of those products/and to yours .

Regards and a happy new year

FK Jazz

[rplace]

You want to ad that 3mH inductor into the circuit don't you? We might have to. Rich is having problems getting things dialed in, and even though I had him flip polarity on the woofers he's still sensing something is off. I'm worried about that phasing issue we talked about. I was about ready to just have him bypass the low pass section in his AK-2's and then have him add the 2.5mH single inductor to his Super AA.

On a completely different train of thought - I would very much like to hear your thoughts on making my DeanG Super AA for the AK series more like the Belle you built. i.e. getting rid of the stuff in the bass bin all together and putting what is necessary on the new networks.

Hey Dean, it has been a few days now and we have a new year. Happy Ney Year to all. So any thoughts on getting rid of the "AK-2 stuff" in the bass bin and installing the "Belle stuff (Inductor???)" on my two khorns?

[Deang]

You know, you really are such a pain in the ***.[]

Go to www.alkeng.com, and download the installation manual for the ALK (Universal Type A Replacement) -- there's something in there that will help you. Just read through it -- you'll understand. We'll need to talk on the phone tonight -- it'll be easier.

[rplace]

Sorry don' mean to be a PITA []

I have read the install instructions (again) and talked with Al via email about this a long time ago. I understand that for the universal A replacement you have to get rid of or bypass the AK-2/3 stuff in the bass bin.

Where might I scare up a couple of inductors (if that is the right term) like I see on my Belle network to use in my khorns? Is this something a person buys or makes? Would it make sense to modify my current networks to include that new inductor and in turn wire my bass bin like Al's instructions suggest. Or should I just put that inductor in the bass bin in place of my current AK-2 stuff?

BTW I should be home tonight. I'll PM and email you my number in case you lost it.

[Deang]

I was going to send you the inductors and have you mount them on the board in the bass bin.

Your phone is ringing.

[sparrowho]

I too am in need of a capacitor update on my 1990 La Scalas. I found that obtaining the 13 uF caps was difficult but struggled on using the suggestions in this thread. I haven't pulled the trigger yet on ordering them as wasnted to bounce my plan off those with better experience first.

I researched the cap values I needed this morning and then guess-ti-mated the pobable best use of my funds. Below is my research notes and possible conclusions:

RESEARCH NOTES: To rebuild La Scala AL-3 networks

Dayton Precision 1% Metallized Polypropylene Capacitors

DAYTON from www.partsexpress.com PMPC-2.0 2.0uF-250V PRECISION AUDIO CAPACITOR 027-214 $2.23 ea need (6)
SOLEN from www.partsexpress.com 68.0uF-400VDC POLYPROPYLENE CAPACITOR $18.43 ea need (4)
UNK from www.partsexpress.com 100V Non-Polarized Crossover Capacitors 68uF-100V NON-POLARIZED CAPACITOR 027-356 $1.30 ea need (4)
DAYTON from www.partsexpress.com PMPC-6.2 6.2uF-250V PRECISION AUDIO CAPACITOR $4.24 need (4)
DAYTON from www.partsexpress.com PMPC-6.8 6.8uF-250V PRECISION AUDIO CAPACITOR $4.45 need (4)

using guesstimate on practical price/performance
DAYTON from www.partsexpress.com PMPC-2.0 2.0uF-250V PRECISION AUDIO CAPACITOR 027-214 $2.23 ea need (6) = $13.38

Create 13 uF with combination below
DAYTON from www.partsexpress.com PMPC-6.2 6.2uF-250V PRECISION AUDIO CAPACITOR $4.24 need (4) = $16.96
DAYTON from www.partsexpress.com PMPC-6.8 6.8uF-250V PRECISION AUDIO CAPACITOR $4.45 need (4) = $17.80
subtoal cost of the 13uF creation $34.76

UNK from www.partsexpress.com 100V Non-Polarized Crossover Capacitors 68uF-100V NON-POLARIZED CAPACITOR 027-356 $1.30 ea need (4) = $5.20

subtotal before shipping cost $53.34

Auricap from www.auricap.com2.000 µF 10% 200V .78 X .90 15.00 (1-9) 11.31 (10-24) 7.98 (25-49)

Auricap from www.auricap.com 13.000 µF 10% 200V 1.42 X 1.65 38.60 (1-9) 28.96 (10-24) 20.24 (25-49)

subtotal of Auricap components with two orders as 68 uF not there would yield $67.86 + $77.20 + $5.20 = $150.26 and require two orders and shipping charges

Hovland Musicap from www.madisound.com 2 mfd 100V $20.75 need (6)
Hovland Musicap 6 mfd 100V $31.20 need (4)
Hovland Musicap 7 mfd 100V $34.30 need (4)

Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 250v PA200 2.0 mfd .0001 13 x 25 0.8 x 25 $1.82 need (4)
Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 400v PB200 2.0 mfd .0001 16 x 25 0.8 x 25 $1.94 need (4)
Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 250v PA1300 13 mfd .0004 24 x 38 1.0 x 40 $4.40 need (2)
Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 400v PB1300 13 mfd .0004 27 x 45 1.0 x 40 $4.91 need (2)

Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 250v PA6800 68 mfd .001 43 x 60 1.6 x 50 $16.63 need (4)
Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 400v PB6800 68 mfd .001 49 x 65 1.6 x 50 $16.86 need (4)

Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 250v PA620 6.2 mfd .0002 20 x 30 0.8 x 35 $2.69 need (4)
Solen from www.solen.ca FAST CAPACITORS METALLIZED POLYPROPYLENE 250v PA680 6.8 mfd .0003 21 x 30 0.8 x 35 $2.89 need (4)

subtotal for all Solen caps using 250v devices is $7.28 + $8.80 + $66.52 = $82.60
using the lowcost and more practical UNK 68 uF devices from PartExpress reduces cost to $21.28 but also requires two orders and shipping charges.

CONCLUSION NOTES:

Auricap solution seems way too expensive so eliminated it early on. Madisound selection was to limited for this project. Solen/Parts Express solution would likely result in higher project cost and less performance than the solution of ordering everything from Parts Express. Additionaly I have been advised that I should add or replace the tweeter polyswitch with a 0.5A device and PartExpress want $1.50 for these with part number 071-254. So even if I choose the "all" Parts Express solution component with shipping it will likely exceed $60.

Bob Crites is sending me parts for my Heresy rebuilds and quoted me a resaonable price on everything I would need to rebuild the AL-3 networks and is using Sonicaps for all but the 68 uF devices. Bob must get very good discount on Sonicaps as I can't buy them as cheap elsewhere for what he will sell them to me. This makes my decision for me and I will order from Bob today. I don't know if the Sonicaps are any better than the Dayton branded units but I trust Bob on this choice even if they are marginally more expensive than the Dayton units.

I was already doing the research for this and had begun to post my message when I got Bob's quote so just added it to the end. I fugure I might as well continue my post as it may help others who want to do the research for themselves as well.

[Deang]

Don't buy the Auricaps from Parts Express -- those are the 450v versions of that cap and it's overkill for crossovers. The higher working voltage version costs considerably more as well. Also, you don't need the quality level of an Auricap in the low pass section -- just use Solen, Dayton, or Jantzen.

If you want to order from them, go with the Kimbers. Get six (6) 2uF and two (2) 12uF. The 12 always come in a bit high at around 12.5 -- well within tolerance (5%). If you really want Auricaps -- get them through www.percyaudio.com

[sparrowho]

Dean I didn't price the Auricaps from Parts Express this morning. One reason was they don't seem to offer a 2 uF in any voltage. I did check www.percyaudio.com but they no longer have the 13 uF cap listed so I would have to combine caps to get the correct value. The Parts Express caps that I considered were Dayton Precision 1% Metallized Polypropylene Capacitors and the part numbers were 027-214, 027-236, and 027-238. Since these seemed to be very good caps and a very good price they seemed appropriate. I have never tried them however and since I ordered Sonicaps from Bob it is likely my Klipsch speaker will never get a chance to try them either. Unless I hear otherwise on this forum I may consider this brand for some DIY speakers for the garage someday. With Solen I did not find a huge price increase in going from 250v to 400v devices and listed both in my research. I would agree that there is no need for the higher working voltage in a crossover network. Might only come into play if the 250v units are backordered.

I probably could have saved a few bucks with the Part Express choice but decided that Bob's price was close enough and I don't have to hope that the Dayton branded caps will be good enough. Peace of mind is worth something to me. The other factor that made it a good choice for me to order from Bob is that he already had my order for caps to rebuild a Hersey networks, so it was easier to just edit that order instead of starting a new one with Parts Express.

[Deang]

My apologies, I didn't read to the very bottom of your post so I missed the part about the getting the Sonicaps from Bob for the AL-3's -- I just saw all those links!