McIntosh XL-1 Crossover Help

[zymaze]

I picked up a pair of McIntosh XL-1's the other day that truly need some TLC. The bass drivers need refoaming which does not seem like it will be an issue unless anyone's got any advice that is unique to these drivers. My question is on the possible recapping of the crossovers. These speakers were made from 1983-92, so they are possibly 34 years old. Given the lifespan of many audio capacitors it seems like recapping might be in order. Does anyone have a schematic of these crossovers? I have looked online to no avail. Some of the capacitors also seem to have odd values (although I am far from an expert on these matters). Here is a picture of the crossover board. Thanks

 

[c_dk]

Roger Russell McIntosh's decades long speaker designer had at his disposal a full size anechoic chamber, the latest B&K measurement tools and management OK to do his own thing. He did. The blue electrolytic is most likely a Zobel across the woofer. Just replace it and be done. Use a electrolytic and a film in parallel to get the value you need. The yellow mylars do not deteriorate.

I probably have a schematic from when I was a dealer and if I get the time I will check to confirm it is a Zobel. I am sure you could buy a schematic from Mac parts.

 

[zymaze]

I probably have a schematic from when I was a dealer and if I get the time I will check to confirm it is a Zobel. I am sure you could buy a schematic from Mac parts.

I've never even heard of a Zobel. Is it a brand of capacitor or a unique type? If you have a schematic that would be great, thank for your time and expertise.

 

[Brice]

I would ditch the wet cap and use a 30uF film cap + 2 uF in parallel.

Mouser Part #: 80-C4GADUD5300AA3J would do it.

I am thinking doing a refresh on my LS340 boards but this one has a 330uF and that will be a problem.

 

[c_dk]

Google Zobel network.

 

[twiiii]

Its a resistor and capacitor placed in the network of the woofer to smooth out the impedance making the other caps and coils work in a more linear fashions with the woofer .

 

[AbSoundLabsMN]

Roger Russell McIntosh's decades long speaker designer had at his disposal a full size anechoic chamber, the latest B&K measurement tools and management OK to do his own thing. He did. The blue electrolytic is most likely a Zobel across the woofer. Just replace it and be done. Use a electrolytic and a film in parallel to get the value you need. The yellow mylars do not deteriorate.

I probably have a schematic from when I was a dealer and if I get the time I will check to confirm it is a Zobel. I am sure you could buy a schematic from Mac parts.

 

[c_dk]

I checked the schematic, it is a Zobel.

RR really used all his toys to manipulate the response of the Philips sourced tweeter for this model, looks to be a 2nd order Butterworth with an added compensating circuit.

 

[AbSoundLabsMN]

McIntosh made two models of the speaker. They were the XL-1 and the XL-1W. The crossovers were different between the two. If you PM me I will scan the two and email them back to you. Locally, since McIntosh doesn't have replacement parts for those units, we refer Clients to a Company called MidWest Speaker, located in Golden Valley Minnesota. They are an excellent Company.

Mark
McIntosh Factory Restoration Facility.

 

[c_dk]

The XL1W was the short lived 12 inch sub added to supplement the satellite speakers. The people that actually have the original factory jigs and such are located in Syracuse NY. They bought out all the Mac speaker repair parts according to the McIntosh service manager.

 

[AbSoundLabsMN]

You can find more information about Zobel Crossover designs at the following link...

users.ece.gatech.edu/mlech/ece4445/downloads/zobel.pdf

Mark
McIntosh Factory Restoration Facility

 

[unfairlane]

Electrolyte caps should not be used in any serious speakers filter, buy the cheapest film-caps instead. 32uF = 2x16uf

https://www.parts-express.com/solen-16uf-400v-polypropylene-capacitor--027-578

 

[zymaze]

Thanks for the information on Zobel Crossovers. Simply Googling Zobel got me a very confusing mishmash of highly technical results and I'm a hobbyist with no formal EE educational background, although I have done a lot of recapping on a variety of audio and computer boards. Thanks Mark for the offer of schematics I looked high and low for them without success. I just trying to figure out the easiest way to bring these back to spec.

 

[c_dk]

But we deal with that goobly gook every day......even a hobbyist has got to want to learn new stuff.

Fix the surrounds and replace the 32 mfd cap and then enjoy.

 

[zymaze]

If anyone stumbles on this thread looking for help on modernizing the crossovers in their XL-1's, that weird value electric blue capacitor is still made, though modernized and now baby blue, by the same company Tecate Industries (T.I.): Axial Aluminum Electrolytic Capacitor 32uF 100V Case Size 18X42 mm. And as of this date can be bought at Tedss.com, Part Number: 61508-0320.

 

[CooknTbone]

If anyone stumbles on this thread looking for help on modernizing the crossovers in their XL-1's, that weird value electric blue capacitor is still made, though modernized and now baby blue, by the same company Tecate Industries (T.I.): Axial Aluminum Electrolytic Capacitor 32uF 100V Case Size 18X42 mm. And as of this date can be bought at Tedss.com, Part Number: 61508-0320.

What should I be looking to pay for a pair of these in good shape ? Seller claims both bass drivers have been reconed by certified pro...

 

[sumicron]

If anyone stumbles on this thread looking for help on modernizing the crossovers in their XL-1's, that weird value electric blue capacitor is still made, though modernized and now baby blue, by the same company Tecate Industries (T.I.): Axial Aluminum Electrolytic Capacitor 32uF 100V Case Size 18X42 mm. And as of this date can be bought at Tedss.com, Part Number: 61508-0320.

Just look here roger-russell.com/idszobel/idszobel.htm Roger's the man who designed your speakers.