Weber WZ68 now NOT recommended on Weber website!

I purchased a Weber WZ68 solid state rectifier on April 20 for $22 plus shipping. It failed today, blowing the fuse in my ST-120. I had used it for only about 20 hours total (became enamoured of an old Mullard GZ-37, but decided Monday to save it, so I put the Weber back in.)
I changed the fuse and replaced the rectifier with the "original" Ruby GZ-34 which Bob supplied. Everything is hunky-dory.
Here's where it gets weird. I went to the Weber site and found it completely redesigned. Prices have been raised. AND there's a large-print disclaimer now re: use of copper-tops in "hi-fi" equipment:  http://www.tedweber.com/wz68
Why the big change in attitude, folks? Could it be that I am not alone in experiencing rapid falure of the WZ68???

It's all your fault ... I KNEW you were trouble when you first showed up!!  

Looks like it's just a website redesign and they included that disclaimer about guitar amps only on all the copper cap listings.

I zipped off an email to them:

Wondering about the new "FOR USE IN GUITAR AMPS. Not designed for use with HIFI tube amps, tube radios, etc. " disclaimer on all the copper caps? New policy, problems, or same thing that just happened to show up with the website redesign.?

Reason I ask, it's common practice to substitute the WZ68 for a single 5AR4 on the larger Latino audio amps ... with good results, I might add.

As far as your issues with the WZ68, maybe just bad luck? They do seem to be rather popular and relatively trouble free with the larger amps. And another buck each isn't all that unreasonable in this day and age ... first price increase in some time anyway.

And furthermore ... oh wait ... that was about it ... never mind.

You are one trippy dude, Mr. sKiZo. May I call you Skizzy?
Well, I only bought the Weber as a back-up. My rectifier of choice is a minty Mullard GZ-37. Now THAT is one solid performer!!! Came in the original military grey-brown box, and will probably outlive me. Hopefully.

This is a critical can of worms. Consider the facts, Ma'am. Without consistent and foolproof power supply, supplied to the actual signal path, how can we expect anything close to the perfection of sound we all strive for?
I just switched out the Ruby 5AR4 for my treasured Mullard military CV378 (GZ37) in my recently-acquired ST-120. Not changing any other levels or settings, I do believe that I hear a palpable decrease in harshness. This when listening to a fairly well-recorded Mozart symphony.
I believe that Weber has, more than likely, experienced an increase in customer complaints which may be due to a loss of control over components, or a simple laxity in quality control, which may indeed lead to a crash.
Caveat emptor, and all that poop.
Any and all precautions are advised.

Mine failed within 20 hours too. I keep meaning to open it up and see what when wrong. Maybe someday.

Diode Soup du Jour, n'est-ce pas? Methinks. perhaps, the Death of Ted Weber in 2009 may have ended an era.

My Weber WZ-68 has worked flawlessly for about 14 months. It replaced the Sovtek 5AR4 that came with my VTA-70 kit. The Sovtek failed after only about 40 days. I suspect Kentley just happened to get a lemon.

I looked at the Weber site; other than the caution about using their Copper Caps in hi-fi gear, the info looks about the same as before, except for the one dollar price increase. Perhaps some lawyer told them to include the disclaimer.

BTW, I agree with sKiZo: this guy Kentley is a trouble-maker! He got me to bid on the "atomic" amplifier; I bid $38.00, they came back with a counteroffer of $3,800.00!!  Now where am I gonna get that kind of money!

You got that kind of money to burn, give me $4500 for this instead. They went for around $1200 in the mid '70's, so that'd be about right in today's dollars.



Sansui's King of Quads ... Just finished up with a full restoration. Here's what came out of it ...



Needless to say, I got a LOT of hours into the thing. Burning it in as we speak, and maybe tomorrow cycle it into the system.

sKiZo will be serving colorfully-garnished salad plates all summer at his estate. Bring proof of dental insurance, and lots of floss.
I prefer the moniker "treble-maker" or, if you must, "bass-trap".
I do sincerely hope that my experience with the Weber Copper Cap is a fluke. If so, I will accept my public flogging with a set of AudioQuest premium speaker cables (banana plug terminations, please) in the town square at sundown on Friday. Bon Appetit!

Perhaps we should remember that any and all products have a failure rate that' a statistical fact, so besmirching the utility or reliability of a product based on one failure without a forensic exam is not very scientific to say the least.

The issue here seems to be with the product not the user and if we are to get to the bottom of this and find out if a component many of us use is viable and worthy of continued use.

I had 2 Weber failures and made some posts on it about three years ago after took the duds apart.

Two observations I made were that the thermistor in one had fried and the second had burnt the wire connecting the wound resistors and one diode was also fried indicating some kind of overheating or voltage spike event had occurred.
When they filed I did not notice any electrical events strangely enough. But it may have occurred and the GFI did its job so there was no flashing or sizzling.

BTW these things are bonehead simple inside and easy to fix.

My solution was to rebuild them both but in two slightly slightly different ways than the stock models. I changed the diodes in one to a more robust type (IN5408).

I used a slightly more robust thermistor in the other and I also heat shrinked the leads on the wire joining the wound resistors to avoid any shorting or sparks if there was a voltage spike or some other anomaly. The cover being copper and a great conductor invites a spark.

I own all ST70, ST120, M125 VTA models and have rotated both of these and the stock models that came with them though my collection and they have been flawless for 3 years of extensive use amounting to a combined total of thousands of hours. Along the way I have consumed several GZ34 tubes. I hate them in my environment and have ceased playing with them.

IMHO the WZ68 rectifiers are an excellent product. The modded versions seem to run a little less hot but I cannot explain that. It is only a bit cooler to the touch. Maybe I am hallucinating but that's what I am observing.

I am sure my WZ68's have been tested severely as I live in Costa Rica and this is the land of voltage spikes and brown outs We get them every couple of days. I also use a surge protector and a GFI latch breaker at the end of the cord to the amps

Either Kentley got a lemon as has been suggested or he did something he may be unaware of that caused his to fail but I honestly feel he should not condemn the WX68 or speculate on it without proof until he has examined what went wrong and why if he can figure that out.

This component meanwhile gets my vote and I think we should not fear using it. It WORKS!!! fine and should be given a fair shake by us until it starts exceed a normal failure rate before it is criticized unduly.

I think there needs to be a formally approved by Bob solution for this problem. Real 5AR4's are just too expensive. New ones are junk. Weber now washes its hands of any promise of reliability for Hi Fi use.  I'm not an engineer, but it seems to me that if amplifiers and pre-amps can be designed, tested, and proven reliable, then the same can happen for the rectification issue.

I would prefer to have that solution presented here, on this forum since I consider this to be the best source of information due to it's direct link to the creators of the products.  Taylor that solution for these amplifiers only, and consider it a factory authorized upgrade or improvement for lack of a better term.

Frank111

I had some early failures with the WZ68s as well in the M-125s, exactly as baddogg1946 described. (Wouldn't have had anything with running tall Maggies and ESS Heils in parallel, dropping the speaker load to about 1 ohm, of course!). Tmadden came up with about the same fix you did, plus drilled ventilation holes top and bottom of the copper-caps. (Even with a proper speaker load, which I now have, the little buggers run quite warm and a little air moving through them can't hurt.) Haven't had any grief now for two years, either with the stock WZs or the Troy-modded ones.
Dunno about the disclaimer on their website now. Maybe guitar players are used to trashing stuff and too stoned to hire lawyers, whereas we discriminating audiophiles are more prickly about such matters . . .

Hey, I gave them a yell ... imagine the response if we could get three people doing it, and singing a bar of Alice's Restaurant as well?  

~~~

Maybe we need a "yellow sheet" copper cap mod as a sticky?

One thought (owch!) ... As mentioned, the metal container is a potential ground point for an arc. Maybe one more mod would be to spray the inside with a generous coat of PlastiDip. It's a good insulator, and if you're worried about the heat, watch this ...

https://www.youtube.com/watch?v=sE3841-1E8s

(And no, I've never had a problem, but mine is strictly a backup and has maybe 50 hours on it is all ...)

Another option ... if heat is the killer, drill vent holes top and bottom. Seems to me I've seen that done ... maybe one of my better hallucinations?

As an alternative, figure out an alternate location for the can cap, and build two 5AR4's into the circuit, all whilst keeping things tidy inside the stock "dynaco" chassis. That'd even be doable in my custom chassis by adding a riser box over the single rectifier that'd be deep enough to install dual sockets ... hmmmmm ... more glow!

(I can already see a problem with me trying to drive two GZ37s with the stock iron.)   ;-}

See, it's problems like this that make me happy I built mine the way I did.

A series pair of UF4007 diodes per leg of the HV secondary coming off the delay board. Haven't had any problems.

Frank111 wrote:Real 5AR4's are just too expensive. New ones are junk.

WHICH new ones? I STRONGLY disagree with you, and I think it is inappropriate to make blanket statements like that.

So which ones are junk? Sovtek? Shuguang/China? JJ? Tung-Sol reissue? Genalex U77 reissue? Mullard reissue?

Have you ever even tried any of the last three I mentioned above? I carry the Tung-Sol and Genalex (I don't carry the Mullard as I've found coin/wafer base tubes aren't as popular as tubes with full bases), and they have been bulletproof, nearly flawless for my customers. If you had concerns about the Shuguang or Sovtek I can understand. I can certainly agree/understand you calling out the JJ! But the recent reissues are typically priced between $35 and $40 or so, and I find them to be excellent performers. I'm through spending big money for old Mullards/Amperexes, I'll be VERY happy to have a U77 Genalex or 5AR4 Tung-Sol in my own gear.

This post will consist of the reply I received from C.J. at the Weber Corp. today without any editorial commentary.

Hi Kent.

I will be glad to help out. Could you let me know what you are referring to when you say disclaimer? I assume you mean where it now says: FOR USE IN GUITAR AMPS. Not designed for use with HIFI tube amps, tube radios, etc.

this has always been the case with these rectifiers, but we thought it best to make it clear in the description of the copper caps on our new website.

given that the WZ68 is a pretty stiff rectifier, it may be best for you to use a WS1 rectifier, which doesn’t have any sag resistors which can heat up and fail in HIFI amps.

let me know if you’d rather we sent you a WS1 instead

I should have mentioned that I use a 20 amp Variac on the circuit that powers my VTA ST-70, reducing the line voltage from 122-23 to about 115-16v. I installed the Variac about the same time as the Weber WZ-68. The lower line voltage should put less stress on the power supply of the amp, including the rectifier.

20 amp Variac

I will wait until Bob chimes in about using the Weber WS1 instead of the WZ-68. Jim McShane's comments on new rectifiers from Genalex and Tungsol are also very enlightening. Jim should have a lot of experience with these modern rectifiers. Stocks of NOS units are vanishing.

[quote="Kentley"]This post will consist of the reply I received from C.J. at the Weber Corp. today without any editorial commentary.

Hi Kent.

I will be glad to help out.  Could you let me know what you are referring to when you say disclaimer? I assume you mean where it now says: FOR USE IN GUITAR AMPS. Not designed for use with HIFI tube amps, tube radios, etc.

this has always been the case with these rectifiers, but we thought it best to make it clear in the description of the copper caps on our new website.

given that the WZ68 is a pretty stiff rectifier, it may be best for you to use a WS1 rectifier, which doesn’t have any sag resistors which can heat up and fail in HIFI amps.

let me know if you’d rather we sent you a WS1 instead




I have used the Weber WZ68 with no issues. Currently I am using Mullards and have the WEBERS as spares.

Kent I am totally new to tubes and recently fired up my M125's

A question for Jim McShane: Are there any new iterations of the venerable GZ-33? Or are the new 5AR4s you cite able to withstand the stresses of a M-125 in full-boogie mode? I tried a Sovtek issue and it did not survive power-up. Glad to hear there are good ones out there.

deepee99 wrote:A question for Jim McShane: Are there any new iterations of the venerable GZ-33? Or are the new 5AR4s you cite able to withstand the stresses of a M-125 in full-boogie mode? I tried a Sovtek issue and it did not survive power-up. Glad to hear there are good ones out there.

I don't know how many have ended up in an M-125, but I have had ZERO failures other than one caused by human error.

I would say though that the M-125 pushes any 5AR4 right to the edge. (4) KT-120s biased at 60 ma per tube is 240 ma., and the small signal tubes need some current too. The nominal current limit is 250 ma - that's according to the Design-Center rating system which is the least stringent, there's a bit higher rating if the Design-Maximum or the Absolute-Maximum rating system is used. So the tube is If I had one I'd be sure the bias was correct and I'd take some action to ensure the line voltage wasn't excessive.

That's no picnic in there for a 5AR4/GZ34! And no new GZ33s are being made.

I should also point out that the Mullard data sheet shows the same 250 ma "limiting value" for the GZ33 with a choke input. Both the tubes have higher peak and surge limits

Kentley wrote:
given that the WZ68 is a pretty stiff rectifier, it may be best for you to use a WS1 rectifier, which doesn’t have any sag resistors which can heat up and fail in HIFI amps.

If the sag resistors can heat up and fail while the rectifier is operating within stated parameters (450mA), then isn't this effectively an admission that the product is improperly/inadequately designed or that the specifications are incorrect?

skriefal wrote:

Kentley wrote:
given that the WZ68 is a pretty stiff rectifier, it may be best for you to use a WS1 rectifier, which doesn’t have any sag resistors which can heat up and fail in HIFI amps.

If the sag resistors can heat up and fail while the rectifier is operating within stated parameters (450mA), then isn't this effectively an admission that the product is improperly/inadequately designed or that the specifications are incorrect?

That is what I fear, sir.
I await Mr. Latino and Mr. Mottram's considered opinion on this. They have been asked. Too many ramifications for a snap judgment.

If the problem is heat, then it would be good if Weber would offer an option with pre-cut ventilation holes or slots in the copper tube. Others have suggested adding such slots in prior threads here.