What do defective phono tubes sound like?

I have noticed some rather loud energy discharges when playing LP's.Sort of an abrupt popping.Not unlike static discharge.I do not get this with my digital playback.
The ONLY change made to my system lately has been a new arm.The problem began immediately "after" it's installation.It was just fine with the previous arm.

I don't want to make this an "arm" mfgr thing(and will not mention arm name)but wonder if the phono tubes in use(very NOS Siemens CCa's,with low hours)can be the culprit.

This is making me pull my hair out,and I have little already.
Any thoughts would be appreciated.
The one easy thing about trouble-shooting tube gear, is the ease to swap out tubes as a first check for a problem. What you describe is very much what I recently observed with a phono stage (ARC MCP-33) power supply tube. There were loud pops and other times it was an oscillating upper-bass tone. When it happens it can really make you race out of your chair! A quick tube swap and it was gone. A day or so later I put the suspicious tube in and the problem was back which confirmed this was indeed the problem and in the trash that tube went.

Another thing to consider here: since this is a new tonearm, there may now be an intermittent connection. Is the cable attached or the same you used before? Removing these can result in weakening the connection, especially at the din. If the level is high and the connection is intermittent this could cause any link in the chain to cause a "spike" but generally more of a hum.

I can tell you for a fact that just becuase they are NOS tubes ,does not always make them NOS..Ocassionally you can receive a tube that tests well at the supplier,but for some reason the tube does not survive the ageing process and you will get Spitting or Sharp distortion noises etc..I recently had to send back a nice pair of NOS Tungsram 12ax7 due to this same situation..I am not in anyway saying this is your problem..Only saying its possible it is..Trying flip,flopping tubes and see if you noise travels with positioning...Also sounds like it may be a Static Electricity problem ..Good Luck
yes to the above posts, but also, get the tubes out and clean the sockets and tube pins. I had an Audio Research unit whose sockets and tube pins had to be cleaned, and the spitting noise was no more.
Do you have back up pairs you could plug in and try first of all?

I'm sure whom ever you bought your gold pin Siemens CCAs from is someone you trust to deliver as advertised?

Re-test the CCAs.

It could of been coincidence this issue occurred just when you switched tonearms.

These are vintage electrical devices, sometimes they will develop problems quickly with a current flowing through them once again.

Also , I,m not suggesting you do this.
Some guys constantly roll tubes. The sockets were not ment for this.
But if you do!....Have a tech check them out

Good luck....
Thanks to all,so far.Originally the problem blew a fuse,and cap in my table's electronics.Got a brand new table(Sota is an amazingly fine company to deal with,and really care about their customer base....BIG TIME).
I spoke to my arm supplier,and was met with sincere concern,but I simply cannot believe my luck is SO bad,that it is arm related.The cable is not played around with alot,and I am very careful about stuff like this.Ditto for the tube sockets!

My frustration is that my friends all know just how fanatical I am about proper maintenance,and component care.All is plugged into an Exact Power EP-15a/Ultrapure,which seems just fine.My CD player plays perfectly.

Of course "now" the pricey(yes I have quite a few back up sets)NOS Siemens tubes are "very suspect",but I am really beginning to feel "worn out" from the diagnostics.I have really sweated alot over this latest fiasco!

Mainly since I have a business,and don't have alot of time(in this economy) to frigg around with such expensive stuff.Actually,I have played around SO much in the recent past,that I just want to get back to normalcy again(like hearing LP's)....."Will this ever happen for me"?That's what I have started asking myself,as I have spent a load of bucks,and time on the hobby as of late,and am feeling the New York Jets curse.

My CD sound is consistent though,so I do have music,but "MAN" I now have such great analog stuff,and I keep running up against this damn roadblock of noise/sudden discharge.In a dedicated room,with dedicated lines yet!!OOOOOHH!!!!Frustration!

I have decided to take off Tuesday,and roll up my sleeves,for some real(dreaded) diagnostics.Tube swaps will be on tap,but it "does" seem odd the problem began the instant the new arm arrived.....Hmmmm?

So,right now it can be a few different things...tubes(hopefully),one of my power cables(doubtful),the arm cable(doubtful),a line conditioner(aren't these supposed to stop this kind of stuff?),phonostage(I would not really mind this,as I would then upgrade to new Teflon caps,so I'd probably be ahead of the curve).Or the new arm itself,but "that" would be a new one to me!!

Now I know why I've been looking hard at the Acoustic Guitar mags as of late(used to be a flat picker).Those limited edition Martins look SOOO nice.....We'll see!

Best to all.
Why not replace the old arm and see what happens. If the problem (popping from the speakers?) remains, then the new arm is most likely not the problem.
But, if your back to vinyl heaven, then perhaps it's time to deal with the new arm.
Hang in there. Keep us posted.
Dear Sirseedy, very strange you post this problem now, because I have the SAME problem occuring recently, and we have quite similar systems ! I am also on the diagnosis pathway, and I never thought of a tube problem . I swapped
recently the 12AX7A NOS Telefunken for military grade Mullards , and wonder if they are the culprits.It is like a big electrical discharge occuring every 10 minutes, but only with my analog system . I borrowed a PS Audio Premier Power plant and proceeding by elimination, apparently it is the phonostage headamp who is picking up AC noise when my REFRIGERATOR switches on. When I unplug the frig this not occuring anymore. Hope this helps.
Another possible source is the unshieled proximal part of the tonearm cable, Purist Venustas in my case, hooked to Graham Phantom, being too close to phonostage and picking ground loops and discharging loud pops. When I separate the tonearmcable from phonopreamp the noise and pops disapear

Any chance it's mistracking? (I know you'd have recognized that, but thought I'd cover all the bases.)

Diagnostic question: do these pops happen in both channels or just one?

I'd put a small wager on a loose connection at the cartridge pin(s). Check those carefully for tightness and clean the pins and clips. For cleaning gold, see the last paragraph.

We had a similar LP-only problem last winter, in the R channel only, which made diagnosis easier. Turned out to be slightly spread connectors in one pin holder of one tube socket in the phono stage. I tightened the two clips carefully with a fine tweezers and the problem was resolved. So when you pull your tubes check the connectors in each hole before reinstalling, and clean all the pins and pin holders of course.

For cleaning gold connectors Paul recommends (and we use) a very gentle rubbing with a paper towel. Nothing stronger or more expensive is needed, nor does it require any chemicals. Gold oxidizes in a layer that's basically one molecule thick and it only takes a gentle buffing to remove. Do NOT use a Magic Eraser! ;-)

Good luck,
Once again thanks for the interest in my dilemma.
Jloveys,my entire system is on regenerated A/C,and dedicated lines,so something like a "refrigerator" kicking in should not be a cause.If I need to go to "that" level of forensics to diagnose a problem,then I think my time in the hobby may be running out.

Doug,nice to hear from you,as you always seem to have some inner input that I might find interesting.Yes,I have checked almost everything you mention,with the exception of tube sockets.
This will be addressed this week.My new cartridge worked flawlessly with my previous arm,so that is out of the equation.I just cannot see how anything about the arm can be the culprit,but who knows,and I have gone out of my way to be respectful of the mfgr.I hope this does not backfire on me!
One "serious" concern is if I blow my tweeters,there is NO replacement for them,as Avalon is looking for a new supplier,and mine are not made anymore.I cannot "live" without "this" speaker,it is "that good",so I shudder when I power up under these circumstances,even with a very low volume setting.
Of course the more I think about this,the more obvious it seems that the tubes are the culprit(only three),but I am guarded here,as I am getting quite insecure about reliability these days."These" super systems are really quite complex,when looked at closely.
You know how happy I was with my old arm,and "if" it is the new one,which took me three months to get(without the old arm,as it was sold to finance the "new")I am going to be a "very unhappy camper".I have had alot of analog down time,since selling my "as you know",beloved previous arm(there is a lesson here).
I really need to put some finality on my upgrade path,and go back to being an LP collector/spinner again!
Of course I DO realize this will all come to a happy ending(I hope)but right now I'm about as down on the hobby as ever.I'm also(really)getting more of a workout Fotzing around with my set-up,than I get in the two hrs I spend at the gym,four times a week.

Best to all
Keep your chin up SirS. Friday night our system sounded terrible. No life, no snap, just dull, dull, dull. I gave up and we went out for dinner. Yesterday I realized I'd moved VTF in the wrong direction. Doh! When I fixed that the music all came to life again. I rewarded myself by demagging some power tubes. Woh! Just like Dan_Ed told me. :-)

I know what you mean about the tweeters in your Avalons. I'd be sick if I killed one of our diamond tweeters but at least I could get a replacement. Like you I don't think we could stand going back to something slower, we are so spoiled. ;-)

Cte500 - if your pins/connectors are gold (plated), read the last paragraph of my previous post. If they're not, a different answer might apply.
Doug,I'd be ALOT happier if I could identify the problem.Usually this is very easy for me,but "this" is getting tiresome.

Also,I hate the thought of blaming the arm,unless I am certain it is the cause,but let's face it,everything was "honky dory" until I made the swap.If it turns out to be a wiring problem in my new arm I'll not be happy,as I was SO patient/understanding regarding it's acquisition.I'm sure you know what I mean.
Obviously,as I now still have the "pop,pop" noise issue,I can rule out the new table.

Question(to anyone)...can faulty arm wiring(in actual tonearm) cause a fuse to blow in a table's power supply,as well as a cap in the control section of the table(this happened in the old(really fairly new)table?My phonostage has 70 db of gain,and the cartridge's output is .48mv,so maybe enough transient distortion can cause this????

BTW,anyone considering a new table,who likes the stuff Sota offers(superb actually)....here is something "incredibly" rare in the hobby.....
When Kirk,of Sota,heard of my table being stricken,he felt so bad that he gave me a new Cosmos,just to take the table out of the equation!!
The guy is INCREDIBLE!!,but there is more.....

The new Cosmos is SO much more "refined/precise/flawless in every way" than my previous(superb series IV)one,it really deserves to be called a "series five".
It is almost as quiet as my CD player,even with the pump for vacuum.I really cannot convey how much effort went into this new table,and it is clear the mfgr went out of his way to do everything he can,in a situation like this one.
Btw,words cannot express how greatful I am,and how far superior this "very latest" Cosmos is "over" the previous
Cosmos was."IT" too was a series IV,but the new table smokes it in precision,and attention to detail.

It is appropriate I mention this,as great customer service is why U.S. mfgrs enjoyed success over the years,and now some are threatened by foreign interests.I doubt one can have such an intimate relationship with mfgrs a continent away.At the very least,it would not be "this" easy,and right now "the hassle factor" is not on my agenda!
THIS new/gorgeous table is one thing I have to look forward to,"if" I can iron out my problems.I did not know the meaning of quiet,in a table,until I set this up Thursday.
If you changed the tubes and you are still experiencing the same results. To narrow it down even further ,borrow a table from a dealer.Any model that you can plug into your system.
Or a phonostage from a dealer or from one of your buddies.

I know its even more work ,but it will tell you right away if it is your new arm.

However I suspect its not.

The out standing quality of your new arm would not have left the factory untested and checked over thoroughly, me thinks.
Stilty,the phonostage can be had,I think.The tubes are most suspect as of now.

As to the arm....I am not so sure about that,due to circumstances which my loyalty may have attributed to.One reason why "if" it is the arm(and it is not taken care of promptly)I will be "peeved"!!

As I said,I am taking a day off Tuesday,to rol up my sleeves on this.
Thanks to ALL for actually giving a darn!
>>What do defective phono tubes sound like?<<

A whiney, complaining, syrupy, effeminate, please feel sorry for me, sort of sound.

Can you hear it?
Sirspeedy, your description of the problem sounds like a static discharge to me. If the arm is improperly grounded it is possible for it to *not* hum, but have discharge problems, especially with low humidity. The needle tracking the LP will create the static charge and if not drained off by the grounded arm, you will get a random static 'pop', which can be quite loud once amplified by your electronics!

A hint is that this problem showed up when you changed arms. If the prior arm is available, I would swap it in and see if that sorts it out. If not, I would test the arm to see if it is really grounded correctly. BTW the turntable should be grounded to the arm too. If not, that can cause static discharge too.
Atmosphere thanks So much for the advice.

Audiofeil,you expose yourself again,as a total jerk,but I've been aware of that for some time.Thanks for the kind words anyway.

Static discharge ! Thanks for your intervention, Atmasphere. I grounded the turntable to arm, separated the phonopreamp from turntable,check tonearm grounding and no more "pops". It wasn't the fridge! Are those static discharges harmful to cartridge coils or any components of the system?
Btw,getting a "new" arm and "new" arm cable...that shoud put an end to it...whew!
Best to "almost everyone"! -:)
Jloveys, the static discharge was likely not been 'seen' by the cartridge. Its often a discharge between the ungrounded arm and the turntable. So no worries!
Atmosphere,your thoughtful/educated response has saved me sweat,and a good deal of headscratching.Thanks alot for being such a decent fellow hobbyist.
What a happy end! Sirspeedy you and Atmasphere demonstrated once more how Audiogon is a nice tool when properly used. I am quite new to this site and learn so much about this magnificent hobby/passion through the great communication you guys have that I hope this will never end !
Jloveys,first off--what an interesting table you have put together!I have some friends who will be very interested in your mod.

Secondly,I won't consider a "happy ending" until I have spun some vinyl for a few,unimpeded listening sessions.

Then joy!
Thank you, Sirspeedy, this is only a humble experiment I tryed, just to see the impact of a full size platter acting as rim drive . It turned out to be very effective at no cost, exept the new superplatter.
What have you tryed yet in your system to get rid of your "pops"?
I sincerely hope it will turn to an happy end for you.
Jloveys,the apparent solution was what Atmosphere mentioned.He has superb experience,and is very well intentioned.I thought through his comments,and it coincided with my dilemma(I'd not been able to spin vinyl for about six months,due to what I thought was going to be an upgrade,with all the back orders,and reliability issues....this should end soon).The arm mfgr realised this too,and was very open to a "new" arm and cable.

thanks for the concern
Bad news, "pops" came back... I am also leaning towards tonearm connection failure, when i move the pivoting bottom of the Phantom awful pops appear.
I thought problem was resolved, but it was a short relief, maybe because I unplugged everything. Monday I take the tonearm back for checking. Fortunately we have a very good aftersale system here in Belgium and they lend me a new tonearm during repair.
Hmm?I experienced that too!Yet,now I have new headaches.
This is becomming as much fun as the last five miles of a marathon -:)....
I would check for continuity between the ground of the table and the chassis ground of the preamp.
Atmosphere,I had noticed my pre giving me some noise,"now" when playing CD's Friday night.The vol control started sounding "whoosh/static like" sounding,as I moved the nob(even a little).
Then,as I stopped CD play,and just moved the vol control to hear what the story was,it (the pre)gave a pop,and I could not get anymore output!!
I simply decided to wait a few days,so as to not get upset,as I've been experiencing too many hassles.
Could the table/arm "ground problem"(if it actually was the arm ground,and not the pre all along) have caused the pre to die on me?...."Oye vey",is this getting annoying!!

Sirspeedy, I would be suspicious that the CD player is making either RF, DC or both. I'd pull it out of the system altogether, as if it is RF, well, that stuff can get in everywhere!

Given what you have told me its *not* the tone arm that did that.

Alternatively, your preamp could have been giving you fits all along, with the symptom masquerading as something else. First thing I would do would be to run the system with no digital at all and see if it works. If yes, let it play and see if it still pops. If not, then you need to see if the amps/speakers are OK. If they are, then you need to talk to the manufacturer about the preamp.
Atmosphere,as always great input from you.Some day I'll introduce myself to you,at a trade show.The nice glass of wine will be on me. -:)
I mounted a new phono cartridge last week. It is a MC with about 0.3mV output. I am using an ARC pre-amp with 100 ohm loading. I suddenly developed an occasional popping noise like a static discharge. (Consistently in the left channel). My room is at 83% RH so humidity shouldn't have been a factor. This afternoon, looking around for related threads I found this one. This thread got me looking at all connections and I noticed that the insulation is worn on my headshell wires. I can see bare copper on the blue wire (Left channel). These wires have silk insulation. I have had them since the early 90's. When I mounted the new cartridge I noticed the exposed conductors but didn't think much of it. The connectors are a little loose as well. Considering that I am amplifying <0.3mV that exposed copper could surely be a problem. So I ordered some new headshell wires.

I took the head shell off today and pushed the connectors on tighter onto the cartridge pins. I also manipulated the silk insulation to cover up the bare copper. I know that is just a temporary fix until I get my new wires. But it seemed to do the trick. I played one side of an album with no pops. I ran out of time today, but will try and make time to play more records tomorrow.

I'll be glad when the new headshell wires come. Hardly relaxing listening to music right now just waiting for another pop to occur.