Westinghouse H-M1600 Console Restoration

[superb82]

I picked up this console off CL a few weeks ago off and I want to get it all fixed up and sweet sounding. It's a 1961 (or so) Westinghouse H-M1600.

I’ve started this thread because this is my first foray into the world of radio repair and, while I’ve done a bit of research before jumping in, I’m hoping some of you experts out there can help me if I run into trouble, or jump in and correct me if I'm doing something wrong. I also thought it could be a good resource for other novices attempting the same sort of thing in the future.

I’ll be starting out (as recommended) with “recapping” the amp and go from there. The unit was working okay when I picked it up but it didn’t sound great and the consensus is that swapping out the old caps is the first step in improving performance. So, I found a schematic, picked up a soldering iron and a few other things, ordered new caps, and pulled the amp out.

This is a picture of my setup. That’s the “patient” there on the left.

It’s a model V-2510-11 with two 12AX7s (phase inv.), four 6BQ5s (L/R outputs), and a 5U4GB (rectifier) on a cool little copper chassis. I think most the tubes are original except the rectifier and seemed to be working although I didn’t inspect them very closely so I could be wrong.

Turning it over you can see the caps, some of which readily appear in need of attention; there was quite a bit of waxy goo dripping off a few of them.

Most the fixed paper capacitors were easy to find exact replacements for (e.g. .047 @ 600v) and the rest were very close. I also managed to find a new multi-section e-cap with almost the same capacitance values as the original. The old one was 80/40/30/10 @ 350 - 475 and the new one is 80/40/30/20 @ 525. From what I’ve read though its okay to replace e-caps with higher capacitance values than the original (even up to 100% higher) so even though one cap doesn’t match exactly it should be okay (?) —correct me if I’m wrong here. I also picked up a couple of resistors in case I happen to be desoldering on the same terminal and can swap them out at the same time with the capacitors; I will also use the multimeter to check if any have drifted out of range and fix those too.

I think I’ve got everything I need so without further adieu, here goes nothing… I'll post the results of the recapping on the other end...

 

[chewie]

:thmbsp:

 

[gadget73]

That one 6bq5 looks a bit odd with the getter baked brown like that. Might be worth finding some way to test those tubes. I half wonder if the cooked looking one is a little gassy, or just has been very well used. Electrical leakage on that one particular tube's coupling cap could have abused it excessively too.

 

[superb82]

Fell a little behind in my project due to forces beyond my control but I was finally able swap out all the caps and a couple of resistors too. Here's pics of the new work and a line up of the "usual suspects." Actually not all of them were that bad, particularly that green one (Micamold Tropicap), but some were way gone.

I haven't soldered all them in yet as I still need to get replacements for a couple of the odd value resistors that tested high. Normally, I would've waited to post until that was done but I've run into something strange and need some advice...

Just off each channel input is a resistor and capacitor wired in parallel (see pic). According to the schematic, the resistors are 220k ohm and the capacitors are 22mmf 10% (so either ceramic or mica, I think). However, upon visual inspection, what's actually there don't look like capacitors. Rather, they look like little short stubby resistors; I tested them as such and they register right around 4700 ohms.

(That's them to the right of each 220k resistor)​

It looks like someone might have worked on this area previously judging by that non-matching resistor in there so maybe it's a mistake. So... anyone know what the deal is with these? Are they indeed resistors or some strange sort of capacitor? And if the former, should I leave them there or take them out and put in the right capacitors? And should I use ceramic or mica? I've attached a copy of the schematic to this post in case it helps. The components in question are R78, C57 (left channel) R92 and C61 (right channel). Any advice is appreciated.

@gadget73 - Thanks for your input on that tube. I thought it looked a little strange too. It was connected to one of the worst shape capacitors so maybe that had something to do with it. Taking your advice I've found a place nearby me (Phoenix, AZ) that said they will test the tubes for me (shout out to Audio Video Choices, Inc. for helping a brother out! Thanks!). I'll let you know what I find out.

 

[gadget73]

I believe those are actually a capacitor, probably a low voltage mica or maybe a paper type. A resistor would not make sense in that spot, nor would a very leaky cap. That cap is for phase correction on the negative feedback loop. You really want that circuit to operate correctly or the amp will either sound very strange, or it could oscillate or do all manner of other unhappy things.

I'd probably use mica caps in there, but if you have ceramic in the right value, they would also work. I have mica caps in stock, so they're my usual go-to for low value caps.

What were you using to test the caps? Usually its not so much value thats a problem as is leakage. Most multimeter type testers can't do leakage, or can't do leakage at a couple hundred volts where those caps are rated.

 

[wa2ise]

Just off each channel input is a resistor and capacitor wired in parallel (see pic). According to the schematic, the resistors are 220k ohm and the capacitors are 22mmf 10% (so either ceramic or mica, I think). However, upon visual inspection, what's actually there don't look like capacitors. Rather, they look like little short stubby resistors; I tested them as such and they register right around 4700 ohms.

You're measuring the cathode resistor on the input 12AX7 triode. It's a sneak path thru the output transformer's secondary to ground, then to the cathode resistor to the other side of that cap.

 

[gadget73]

looking at the schematic again, he's absolutely right. Its the cathode resistor via the transformer secondary. 4700 ohms makes perfect sense if it was measured in circuit since thats what the cathode resistor is.

 

[superb82]

I got the remaining resistors and everything is soldered in. I used ceramic caps (since it's all the parts store had) to replace the strange caps on the negative feedback loop discussed above. They aren't an exact match but close enough I think (27 mmfd instead of 22 mmfd). I tested one of the old ones with the DMM again after I had them out -- 0 resistance (which makes sense according to your explanation) and 50 mmfd capacitance.

Almost ready to get this thing powered up after I test the tubes, but before I do that, I'm wondering if should I do anything about these output transformers?

The one on the right/bottom doesn't look so good but I know that doesn't necessarily mean anything. I think is also responsible for the large amount of wax in the chassis. Is there anyway safe way to test it? Should I just get a new one? The Photofact lists the primary impedance as 7500 ohm CT and secondary as 6-8 ohm and based on the suggested replacements I would need a 15w, 40ma, push-pull, universal output transformer (like this).

And as far as powering up goes, how essential is a variac or dim bulb tester in this case? The unit was working when I aquired it so does that mean it should be fine? What about if I end up installing new output transformers first?

@gadget 73 - I'm using a Fluke 17B DDM to measure the capacitance, not the voltage. I should have been clearer about that.

 

[gadget73]

Ohm it out from center to each end on the primary and compare it to the other one. Check the secondary as well, and make sure there is no continuity from primary to secondary. basically if both read the same, they're probably OK.

That Hammond transformer isn't spectacular. 100hz to 15khz is probably worse than the stocker. If you're going to change them, you may as well upgrade. Edcor has some nice ones that would give you more solid bass response if you do want to make changes.

 

[superb82]

Just got the tubes tested today and all except three are shot or damn near it (that orange lookin one barley even registered).:thumbsdn: The only ones that tested in the okay range were the rectifier and one pair of outputs, but since I have to change the other pair I just ordered a quad of them so both sides will sound the same. So much for my $100 budget, but oh well... I'm all in now.

Since I'm breaking the bank anyway, I think I'm gonna go ahead a just put in new transformers too to make the most of these nice new tubes; and if nothing else it will avoid more waxy messes. So I need 7500 on the primary and 6-8 on the secondary, but I can't find anything from Edcor that's an exact match on the primary side. How much wiggle room do you have with that? And on the secondary, should I go with 6 or 8? I'm thinking something from their XPP line like this, but without the center tap on the secondary (unless I can just not use it?). Thoughts?

 

[gadget73]

Those also might be a parallel move. I'd probably use something like one of these two if I were looking to upgrade

http://www.edcorusa.com/p/410/gxpp15-8-8k

http://www.edcorusa.com/p/799/cxpp25-ms-8k-23

I actually have the 40% tap version of that second one on my Magnavox 6bq5 amp. I've been told the 23% one is actually better for cathode bias 6bq5 setups though. I don't know this to be absolute fact, but my 40% one seems to work fine. Or you can just not use the screen taps and run it straight pentode mode like it probably is now.

Either way, I'd run 8 ohm or maybe a 4/8 ohm. Not that many speakers exist in 6 ohm, so unless you happen to have a set, I wouldn't go for that option. 6 ohm speakers generally work fine on a 4 or 8 ohm tap anyway.



Honestly, if you plan to run this in the original console, I would probably not fool with the output transformers just yet. The stock ones likely match up to the speakers fairly well, and providing more bass capability in the amp will quite possibly just make the stock speakers sound lousy.

 

[superb82]

I took your advice and am going to hold off on the transformers for now. I tested the old ones and they measured nearly the same and almost exactly to the values on the schematic so I guess they are hangin' on after all.

I put everything back together, installed the new tubes (JJ 12AX7s and EL84s), and brought it up on a my cheapo variac last night. Everything went swimmingly. No smoke, no pops, no fires! Not bad for the first time out, if I do say so myself.

​

It sounds much better now but I wonder if it could sound better still... What should I do next? I'm thinking about maybe going for new speakers. The stock ones are loud but they don't really have much presence or range (which is to be expected, obviously). The turntable could probably use some maintenance too. And what about the tuner? I noticed a lot of old caps and tubes in it that could probably use changing, but I've heard that so long as it works, to leave it alone as tuners can be pretty touchy and hard to work on. What would you guys do next?

 

[Wigwam Jones]

Have you replaced the caps on the speaker crossovers? I'd look at those. Nice work, by the way. Very nice and great photos, thanks for posting all of that!

 

[gadget73]

Crossover caps would be a good first step. Its probably just a single, so easy enough to replace it. A lot of console speaker arrangements and just speaker compliment in general isn't spectacular though. Having both channels in one big hollow box doesn't tend to do amazing things for seperation. In my own console, the stock tweeters (mine is a 3-way arrangement) are kind of terrible and don't "tweet" much. Its more like a double midrange, plus the woofer runs full-range so its got a lot of honk in the middle, but not much at the top or bottom. I don't expect mine will ever be a bass machine, but I think with a real tweeter and a crossover that cuts the mids out of the woofer, I can get it to produce a more balanced sound at least.


For the tuner, if its got paper caps or electrolytics, I'd change them but nothing else. Tubes don't go bad that much, and if the tuner functions, they don't need changing. The alignment-critical caps in the tuner will usually be ceramic or silver-mica, which tend to be very reliable over time compared to the papers or electrolytics.

Turntables always need a tuneup after 50 years. Whats in there? Might be worth upgrading it to a moving magnet cartridge with a matching preamp, but not all changers will accomodate that sort of thing. Also possible the best move with that is to just upgrade it to something else. I like record changers, decent ones at least, but there were a lot of really crappy ones made too.

 

[FMB42]

Yep, replace those crossovers caps and run it a bit. Then I'd consider replacing the speakers. And, like Gadget73 says, crossover upgrades might take you a step farther in sound improvement. But then again, the characteristic console sound might be something worth keeping.

Meanwhile, congratulations on the great job you did on that beautiful console.

 

[analog addict]

Very nice job for a first go. You might want to look at the amount of space underneath, and perhaps get some opinions on how to either improve the sound via driver change, or possibly even shoehorning in some complete speaker enclosures underneath to maintain the vintage look while improving the sound. I'd make some measurements, and consider starting a new thread in the speaker sub forum. Might make for a very interesting continuation of your project....

 

[superb82]

So the clear consensus is to change the crossover caps next. On it (I'll also recap the paper and electrolytics in the tuner while I'm at it). We'll see if that perks it up a bit, and if not then maybe I'll segue this project over to the speaker forum as suggested and try to come up with a plan B. I'm not so much concerned with keeping the true "console sound" per se --I like it mostly for the looks-- but I do want those tubes to sound and good as they possibly can while maintaining some authenticity. Anyway, to be continued...

The changer is a VM 1571 (I'll post pics tonight). Keep it and tune-up or upgrade? And if the latter what should I get?

 

[gadget73]

I don't have much experience with V-M changers, but the ones I've fooled with have not impressed me all that much. If I wanted to use it seriously, I'd probably be looking for a Dual or an Elac or one of the better Garrard models. Pics make it look like the V-M has that hollow plastic arm with the weight spring deal, and generally those are just not amazing performers. Apparently they made some nice models, but I've never run into one of their upscale versions myself.

 

[Omegaman]

Congratulations and good job. You might let the capacitors burn in for awhile then it might sonically mature

You could get the changer and tuner working but the real power of these consoles is in the aux input

Modern input through vintage amp

 

[superb82]

Finally got those crossovers fixed up and wow! It has made the biggest difference of anything so far. Although still not perfect, everything is so much clearer now. I had to do a little jerry-rigging to get the new cap hooked up since I couldn't find a non-electrolytic crossover that would fit in the old space (I could have used a small electrolytic again but I've read that isn't recommended). Here are the pics:

I also tore down, cleaned, lubed, and rebuilt the turntable... I won't go into details but suffice it to say I would not recommend it. That think was a royal PITA to get back together right and I'm surprised I even managed. :thumbsdn: But all's well that ends well I suppose. I didn't get to the tuner yet (on account of the turntable taking a lot longer than expected) but it's working well enough that I'll take care of it later.

The biggest issue I'm having now is with the right channel. The output is a lot weaker than the left. I haven't isolated the problem yet between the amp and the speaker but I'm going to switch the leads and see whether the problem moves or not and then either go through the amp again or see about the speakers. The other thing, and this might just be an old console deal, is a very pronounced hum that has developed (it might have been there before too and I just didn't notice). It's seems to be coming mostly from of the tweeter/horn and is present on both channels. It's tolerable on mono but is way worse when I switch to stereo and worsens the longer its on. Any advice for troubleshooting either of these?