Snell Type 1 Crossover Rebuild

[lt_texan]

I have a pair of Snell Type 1's. I love them, but the tweeter's fuse holder on the left speaker broke, so I thought I'd take this opportunity to rebuild the crossovers and install them in an external box.

My idea of rebuilding crossovers is to replace the caps and rewire, leaving the chokes alone.

Here's what Type 1's look like...



And a bit of a close up...



Here's the crossover...



Here's the crossover schematics drawn out. You can see on the woofers, there is a 3 way switch that adjusts the midrange level. I haven't mapped this out yet. But the switch in the center is "normal" with the up position being "Increase 1" and down position being "Increase 2."

(These are Type 1's even though I titled it Type A's!!!)





As you can see, there are MANY capacitors. I count 22 for the pair of loudspeakers. With 12 big ones in the woofer x-over.

Also, I plan on replacing the wiring with multiple strands of individually teflon insulated silver plated copper wiring.

Before I start this project, I would love to hear any opinions from the team!

Thanks in advance,
Dan

[speaker dave]

Part of the reason for the multiple caps is that Snell allways engaged in production tuning of each crossover. For whatever curve the particular drivers gave they would adjust key components to get the curve within +-0.5 dB of the reference. Typically they would start with low cap values and add small increments to get to the right value. Also inductors were a little high and turns were pulled off as needed.

Make sure you keep the right crossover with the right cabinet and drivers.

David S.

[lt_texan]

Absolutely. I will keep the drivers and crossover components separate and put them back with the correct box.

On the chokes, you can see where some have been tuned by unwinding some coils.

The crossover are signed and dated by the engineer.

Thanks,
Dan

[dantheman]

Those are cool speakers Dan! Do you know what year they were made? I'd imagine those caps are ready to be replaced, but I really don't know. The driver surrounds look like they are still in good shape, but it's hard to see from the photo on my monitor. Looks like they were using the floor as a mirror similar to the CBT without the array.

I'd measure each individual group of caps all together to see the precise value. With all the variance/tolerances of the caps, they may be significantly off from simple addition of stated values. Of course maybe those old lytics won't measure right so addition may actually be better. If the measured value is no where near the sum, I'd go with the sum. If none of the experts here chime in I'd ask at a classic speaker forum before performing any surgery.

Dan

[speakerdoctor]

Originally Posted by dantheman

Those are cool speakers Dan! Do you know what year they were made? I'd imagine those caps are ready to be replaced, but I really don't know. The driver surrounds look like they are still in good shape, but it's hard to see from the photo on my monitor. Looks like they were using the floor as a mirror similar to the CBT without the array.

I'd measure each individual group of caps all together to see the precise value. With all the variance/tolerances of the caps, they may be significantly off from simple addition of stated values. Of course maybe those old lytics won't measure right so addition may actually be better. If the measured value is no where near the sum, I'd go with the sum. If none of the experts here chime in I'd ask at a classic speaker forum before performing any surgery.

Dan

Agree, you should go with the sum rather than a measurement. Too many NPE's there and any one could be bad based on their age and reputation.

A key decision you need to make is whether to recap with new film caps or stick with NPE's (mew ones of course) and a pF ceramic disk BP just like they used.

[lt_texan]

Originally Posted by dantheman

Those are cool speakers Dan! Do you know what year they were made?

Not sure what year exactly, but I think '80 or '81. there is almost no documentation on these speakers. the Snell website didn't even list them in their speaker archive!

Originally Posted by dantheman

The driver surrounds look like they are still in good shape, but it's hard to see from the photo on my monitor. Looks like they were using the floor as a mirror similar to the CBT without the array.

The surrounds and cones are in great shape. Word is that Peter Snell bought the drivers and then coated them with god knows what. I can see on the back side of the cone that it looks to be clear poly-something , with an applied black coating on the front side. The surrounds look to be some kind of rubber with the same black coating applied to the cones. The tweeters are in great shape.

Yes, the idea was the tweeter mounting and ramp eliminated floor reflection.

Good advice on the caps. I think adding up the uF is the way to go. I expect to buy plastic film caps. I priced out Hovland Music Caps for the pair at over $500!

I might go this route for the tweeters, but maybe cheaper plastic caps for the woofer.


Thanks,
Dan

[speakerdoctor]

Hovland has gone out of business. I hope you got a great price.

Best value for the $ are Sonicaps IMHO.

[lt_texan]

Here's a review on the speakers....(sorry, these are big)


http://members.rennlist.org/lt_texan/Snell1p1.pdf

http://members.rennlist.org/lt_texan/Snell1p2.pdf

[lt_texan]

Originally Posted by speakerdoctor

Hovland has gone out of business. I hope you got a great price.

Best value for the $ are Sonicaps IMHO.

ouch, must have been a old website. thanks for the recommendation!

[speakerdoctor]

Originally Posted by lt_texan

ouch, must have been a old website. thanks for the recommendation!

If you find the sound a bit bright after the film recap, you should reconsider NPE's or, adding a low value (0.25-0.5 ohms) resistor in series with the film caps to compensate for the normally higher ESR of NPE's than film types. This will restore the overall system integration that matches the original.