Model 19 Crossover Help

[doclamb]

I've wanted to upgrade my Altec Model 19 Crossovers so 2 weeks ago I removed them from the cabinets, removed the plate that held the old electronics and had a larger plate made to attach the new larger caps and resistors. I'm using the original iron core inductors and keeping the original L-pads just transfering them to the new plate.
I used the old crossover plate with everything still attached as a template and then attached all the new electronics (Foil caps) in the same position on the new plate as the originals. I checked and then rechecked to be sure that everything was identical to the original. After reinstalling them today....nothing, not a sound. I can solder pretty well but really have a grade school level of electronic education and experience. Suggestions on where to go from here for the obvious amateur. I'm in the Portland Oregon area so any help from a local or a local tech, in addition to any helpful advice would be greatly appreciated.
Thanks in advance.
Rob

[rgwalker]

I've wanted to upgrade my Altec Model 19 Crossovers so 2 weeks ago I removed them from the cabinets, removed the plate that held the old electronics and had a larger plate made to attach the new larger caps and resistors. I'm using the original iron core inductors and keeping the original L-pads just transfering them to the new plate.
I used the old crossover plate with everything still attached as a template and then attached all the new electronics (Foil caps) in the same position on the new plate as the originals. I checked and then rechecked to be sure that everything was identical to the original. After reinstalling them today....nothing, not a sound. I can solder pretty well but really have a grade school level of electronic education and experience. Suggestions on where to go from here for the obvious amateur. I'm in the Portland Oregon area so any help from a local or a local tech, in addition to any helpful advice would be greatly appreciated.
Thanks in advance.
Rob

Rob: I am good with a soldering iron but am no tech when it comes to electronics theory. I had a friend inspire and help me with upgrading a pair of Model 19 crossovers with amazing results. I use them with a hybrid three way Altec/EV/Heil system and had to add a cap for the tweeter. It's the most dynamic and musical system that I've ever experienced; let alone own. Four months later I still listen to music in awe and for hours on end. The caps? The coils? Both? I don't know but I hooked up the system before the crossover upgrade and the difference was stunning and should be the same for you. I owned a pair of Model 19s with stock, and likely not working properly, crossovers and they rocked.

Bob Walker

[doclamb]

Thanks Bob, I think I have found the problem. The old terminal board which I didn't use, is riveted to the aluminum plate at 4 locations via a small piece of metal that is then riveted to one of the woofer and HF terminal posts. The metal plate serves as a common ground at these 4 locations. I didn't see this in the original crossover thinking that it was simply a way to connect the strip to the plate.
Nice work on your crossovers and I'm glad to hear your enjoying the music.
Thanks again,
Rob

[rgwalker]

Nice work on your crossovers and I'm glad to hear your enjoying the music.
Thanks again,
Rob

Rob: I have to thank Evert who lurks around here as AltecLansingFan. He responded to an Ebay auction for my Model 19s and when he told me about his system, which uses the Model 19's 416-8B and the crossover, I had to try it.

Bob W

[Plink]

I owned a pair of Model 19s with stock, and likely not working properly, crossovers and they rocked.

Bob Walker

Hi Bob,

and I bet I own those exact stock model 19s now ;). I still haven't changed the crossovers and yet they sound terrific. btw, I don't think they are working properly either but they sound great! cheers, Paul :)

btw, looks like you just decided on all solens and kept one of the inductors?

[rgwalker]

Hi Bob,

and I bet I own those exact stock model 19s now ;). I still haven't changed the crossovers and yet they sound terrific. btw, I don't think they are working properly either but they sound great! cheers, Paul :)

btw, looks like you just decided on all solens and kept one of the inductors?

Paul: Those are the ones and I'm glad that you're enjoying them. I would love to hear the upgraded crossovers with a pair of Model 19s. If you ever want to try it I'll send you the schematic although it's a simple changeover with the same values.

BTW. I've been promoting Just4U here and on Ebay and I have you to thank for that hook up.

Bob W

[Plink]

Bob, don't thank me. thank google! i wonder if anyone else has had success using Just4U. the price was good and they were professional all the way through, particularly in dealing with my nervousness.

Doclamb, please let us know how your crossovers sound. I have yet to change mine over simply because I'm enjoying the speakers so much as it is. I'm hoping an updated crossover brings a smoother, more liquid sound yet still retains the amazing dynamics.

- Paul

[doclamb]

Paul, my history with the 19's has been interesting. Let me start by saying that I feel that they are one of the best bang-for the buck speakers that can be purchased today. Four years ago I found a set of 19's that were in OK condition (the HF dirvers didn't work) on CL and refurbished them by sanding and finishing the cabinets, sending the drivers to Great Plains, caulking the horns and purchasing new x-overs from an aftermarket company that sells them (not GP's). When finished I felt that they were very good, but lacked some warmth, and exibited a little glare/hardness on top. I was using them with a very good EL84 pentode push/pull 10 watt Audio Note OTO at the time and in hind site I believe the choice of poly caps and resistors in the new x-overs contributed to the high end glare more than anything else. After a year I sold the 19's and over the next year or two I enjoyed Acoustic Zen Adagio's and JM Reynaud Offrande speakers both on higher power tube and SS amplification. What I continually missed though with the new speakers is the ease of dynamics and full sound that the 19's posses, so like any audiofool I found another set of mint 19's and brought them home. I've had the new set for a year listening to the original 19's crosssover for the first time. My impression is that the original x-overs are better than the aftermarket x-overs and that the original x-overs were engineered/fit the speakers better. I would discribe the 19's with original x-overs as 'a bit' soft in the bass and a bit dark at the top end - just enough to 'warm up' the sound a bit.

So why mess with them by building another x-over?
Well I've saved the original crossovers so that I can reinstall them if necessary, but what I'm attempting to accomplish is to take the best from the first x-over, clarity, extension, and dynamics without losing what makes the original crossover appealing to me which is a combination of balance, smoothness and warmth and put them together.

To start with on the crossovers I've built I've retained the original inductors and L-Pads. The parts used were 8.2uf Mundord SIO, 15uf Mundorf supreme, 21uf Sonicap and 6uf Dynamicap-L. Duelund resistors were used. Neotech 18ga. Teflon Copper was used for all internal speaker x-over and driver connections. After dealing with the grounding issue above I reinstalling them and hooked them up to FM on a NAD reciever for break in (recommended 300 hrs on the caps). I didn't sit and listen to them for the first 50 hours but what I did hear when passing by was bad. Tight, constipated, no bass, "oh schitt" what did I do kind of sound. After 100 hours they had calmed down considerably to the point where the highs were smoother, and the bass had returned. This weekend at 150 hours I hooked them up to my tube 6V6 15watt PP system for 4 hours of play. All listening done via CD as I'm waiting on a new cartridge for my TT to arrive later this week.

So, are the new crossovers better? Well they are clearer, faster, more dynamic, and have a better defined mid-bass. They have none of the hardness and glare of the after market set, but, but, but, do they retain the balance, smoothness and warmth of the original x-over's?
Yes and no. The overall balance has shifted slightly upwards. Not always a bad thing as the 802's has been accused of not having enough extension. I might speculate now that perhaps it's not just the driver. With a slight upward tilt the music seems clearer and the Mundorf's are definitely smooth, with no glare although they still seem tight at the very top. Some of the midrange and low end warmth of the original is gone because both are better defined or articulate. I found the sound with the original x-over even in a speaker this size could be sweet and even intimate when the speakers were set up properly. The present x-overs sound is bigger and they've taken on an electrostatic speaker-like clairity and size if that makes sense. (If not sorry I don't do this for a living)

Would I recommend this to others? I don't know YMMV. Part of the appeal of the vintage speaker is that they are vintage in all their glory. Warm, sweet, relaxing, smooth and all the non audiophile things that go with them. Why mess with a good thing?
In the mean time these new x-overs are still breaking in and I'll wait for a month of play before forming a final thumbs up, or thumbs down opinion.
Hope this helps.
Regards,
Rob

[Plink]

Thanks Rob. It's really valuable for me to hear other's experiences with this speakers.

Since my speakers sound as good as they do, I had planned to keep the orig crossovers as is and try a new one. Or, simply replace the caps and resistors in the orig and keep the inductors. I had originally thought my Altecs were too bright but that turned out to be a room/system problem and also an issue with the L-Pad. I was also listening to old Mercury mono classical lps and those tend to be a tad bright to begin with.

The 19s I have now exhibit the character that you and many others describe. And that is a wonderful character. I still hear a lot of details in the sound, I might add. I guess I'll just have to build the new crossover and see what happens.

System here is mostly vinyl based w/300B amp and 76/6F8G/6SL7 line stage/phono.

[doclamb]

Paul, good to hear that your enjoying your 19's. If I might add a thought for those that want to build something different from the original x-overs. Build it outside the cabinet on a big board with lots of room. Be ready to spend some $$ because you'll want to try different caps. Spending more $$ on caps doesn't insure better sound, however I've found that better caps don't have the glare of the lower priced caps. I'd love to try some Jensen PIO's or Sprague Vit Q's but I'm locked in to what I've built for now. I see no reason to change out the original inductors, but some may. Once you find the sound you like you can transfer everything onto something permanent, but I'd still keep everything out of the cabinet. Leave the originals x-overs in if you can, and work around them. You may want to hook them up again some day. Just my thoughts. My rebuilt x-overs continue to improve every day. I'm letting them run-in all week and will sit down with them this weekend when they'll have 250+ hours on them.
Regards,
Rob

[Zilch]

ZilchMod M19:

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30595&stc=1&d=1200899899
Skywave-Rider's build:

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=31046&stc=1&d=1203366567

[doclamb]

Very nice clean job.