I ruined one 300B output tube last night...

flez007 · Feb 14, 2014

that is the rough part of i) owning tube gear, ii) make cable changes "on the fly" and iii) have audiophiles friends at home!

Now I need to get a matched pair for my Conquest amp (did I hear four to match the other mono block??)

zztop7 · Feb 14, 2014

Tube Matching test - not so great

I looked into buying PSE Parallel SET amps years ago & talked to heavy [knowledge] tube techies. Here is what I learned:
You can put in perfect match tubes & in a little while one of the tubes will be dominant [not sex] & put out more power.
This is NOT advice, but if it was my PSE I would just throw in the same tube and not worry about matching.
A lot of matched tubes are not that well matched.
The tests they usually do to match tubes are not the operating conditions of your PSE.
Do some research.

zz.

LL21 · Feb 15, 2014

Hey Flez007...I am really sorry to hear that. I feel for you...hate when stuff goes wrong, particularly just when you are in the middle of REALLY enjoying with friends, etc.

I guess it gives you the "opportunity" to go hunting for some awesome 300Bs?...an 'upgrade' to what you already had? may as well look at the bright side of things!

Hope it all gets back to perfect super-soon.

microstrip · Feb 15, 2014

flez007 said:
that is the rough part of i) owning tube gear, ii) make cable changes "on the fly" and iii) have audiophiles friends at home!
(...)

Sorry to know about this disaster - but think that if it had happened with a solid state amplifier most probably it would have shorted several transistors, burned a few resistors and you would have to send it for an expensive repair ... I am not inventing, it happened in my presence to a friend in an audiophile session comparing cables using his big and heavy SS amplifier. He just pressed the power switch of the amplifier twice to change the RCA input the cables and the ground was floating ...

JackD201 · Feb 16, 2014

You could have easily burned some tweeters too.

Try the KR classic 300Bs if you get the chance flez. They are what I use so I can prolong the lives of my WE collection. IMO they are among the best non WE 300Bs.

andromedaaudio · Feb 16, 2014

Very unfortunate flez , always take the power off especially when changing powerampcables , I ve had my share of misfortune

I never heard the KR s would like to try them someday .
I only compared the Sophia electric RP and the FUll music 300 B/n .
Royal princess is the winner a tad more transparent and doesn't sound tubey at all(rolled off , slippery bass )

andromedaaudio · Feb 16, 2014

Well actually I did hear KR 845 tubes in the zanden 9600 , it sounded awesome, no soggy bass there and very dynamic

JackD201 · Feb 16, 2014

I liked the Princess too. Lovely highs on those tubes.

flez007 · Feb 22, 2014

UPDATE

The damage is diagnosed and on it´s way for a full repair, it won´t come cheap:

One 300B Audio Note tube - GONE - ordered two Sophia's 300B tubes
One coupling paper-in-oil cap - GONE - ordered Jensen tin/se/paper in oil caps

I bought this amps used, and looks they had some previous "work" (minor) that included a pair of ICs rectifiers/filters to protect tubes from AC voltage - changing them since they were limiting the current that the output tubes need (they were glowing to low)

+ labour, import taxes, etc....

the good thing is that my tech will make them live longer and will sound a tad better once repaired (I had of course to have both amps serviced to keep them identical)

...eagerly waiting to have them back, and thanks all for your lines of support

flez007 · Feb 22, 2014

..on other thing...

My tech says it is very strange to have the coupling caps in short-circuit, does anybody had the same issues and figured that out?

flez007 · Feb 22, 2014

zztop7 said:
I looked into buying PSE Parallel SET amps years ago & talked to heavy [knowledge] tube techies. Here is what I learned:
You can put in perfect match tubes & in a little while one of the tubes will be dominant [not sex] & put out more power.
This is NOT advice, but if it was my PSE I would just throw in the same tube and not worry about matching.
A lot of matched tubes are not that well matched.
The tests they usually do to match tubes are not the operating conditions of your PSE.
Do some research.

zz.

Thanks zz, it all looks that the circuit configuration of the Conquest amps is not that sensitive to matched pairs, I am getting Sophia´s tubes since we had some doubts on the KR ones.

zztop7 · Feb 22, 2014

flez007 said:
Thanks zz, it all looks that the circuit configuration of the Conquest amps is not that sensitive to matched pairs, I am getting Sophia´s tubes since we had some doubts on the KR ones.

Good morning,

The carbon plate tubes do NOT work for me [Tone].

I use & love the metal perforated plate 300Bs. They call them mesh, but that is actually wrong. I have 3 different tube names & they all have the same internals; although some are globe & some are bottle shaped glass. During your tube research you may have found that the Sophia tubes come out of a factory that produces many different names - my opinion is: same tubes if they look identical [maybe Sophia has different matching].

Please clean your New tube pins with 99 - 100% alcohol [allow to air dry] before installing. Do not accidentally flood the base.

I hope you are able to buy locally so that if you have a tube problem, you can easily return them. I personally would have a concern if one tube ran extremely bright & the other was dim. If there was a little difference in brightness it would not concern me [personal opinion - please do your own research].

Best to you,
zz.

flez007 · Mar 1, 2014

Update (2)

i managed to get one pair of new JJ 300B to try, I cancelled the Sophia's order after additional investigations - both amps are fully repaired now and are playing right now (one with the new JJs and the other with the old AN branded tubes - don't kill me!, this will not be the final setup).

i am liking the JJs! - anyone that have tried them and willing to comment?

mep · Mar 1, 2014

zztop7 said:
flez007 said:

Thanks zz, it all looks that the circuit configuration of the Conquest amps is not that sensitive to matched pairs, I am getting Sophia´s tubes since we had some doubts on the KR ones.

Good morning,

The carbon plate tubes do NOT work for me [Tone].

I use & love the metal perforated plate 300Bs. They call them mesh, but that is actually wrong. I have 3 different tube names & they all have the same internals; although some are globe & some are bottle shaped glass. During your tube research you may have found that the Sophia tubes come out of a factory that produces many different names - my opinion is: same tubes if they look identical [maybe Sophia has different matching].

Please clean your New tube pins with 99 - 100% alcohol [allow to air dry] before installing. Do not accidentally flood the base.

I hope you are able to buy locally so that if you have a tube problem, you can easily return them. I personally would have a concern if one tube ran extremely bright & the other was dim. If there was a little difference in brightness it would not concern me [personal opinion - please do your own research].

Best to you,
zz.

Click to expand...

Heed ZZ's advice. Failure to do so will result in fireworks and I don't mean the "Ooh and Ah" type either.

zztop7 · Mar 1, 2014

flez007 said:
Update (2)

i managed to get one pair of new JJ 300B to try, I cancelled the Sophia's order after additional investigations - both amps are fully repaired now and are playing right now (one with the new JJs and the other with the old AN branded tubes - don't kill me!, this will not be the final setup).

i am liking the JJs! - anyone that have tried them and willing to comment?

Hi flez007,
I am glad you are listening to different tubes & enjoying them. I have not tried the JJs.

Please send me a Private Message [that way I will for sure see your response] if you ever try mesh plate tubes [perforated metal].

Best to you,
zz.

flez007 · Mar 8, 2014

Update (3) and final

well, it looks like the saga is over, the amps are up and running and just waiting for my decision for a 300B replacement, currently one has new JJ tubes and the other with old but good measuring Audio Note branded ones.

for those interested, I paid around 900 dlls for the full repair including the two new tubes and coupling caps (thin cap, paper in oil).

Thanks all for your advice and supporting lines.

LL21 · Mar 8, 2014

flez007 said:
Update (3) and final

well, it looks like the saga is over, the amps are up and running and just waiting for my decision for a 300B replacement, currently one has new JJ tubes and the other with old but good measuring Audio Note branded ones.

for those interested, I paid around 900 dlls for the full repair including the two new tubes and coupling caps (thin cap, paper in oil).

Thanks all for your advice and supporting lines.

ahhhh...always great to be back, eh? congrats and enjoy...

JackD201 · Mar 8, 2014

Hi Flez,

Just curious. What were your doubts about the KRs? They are some of the most, if not the most, robustly built new production tubes. Hand blown glass and hand assembled innards as well as a very good evacuation oven. They are also now supplying tubes to very picky companies like Allnic.

flez007 · Mar 8, 2014

JackD201 said:
Hi Flez,

Just curious. What were your doubts about the KRs? They are some of the most, if not the most, robustly built new production tubes. Hand blown glass and hand assembled innards as well as a very good evacuation oven. They are also now supplying tubes to very picky companies like Allnic.

Short life and reliability ... Still confirming with Eunice.

cjfrbw · Mar 8, 2014

I like the JJ 300b. They don't quite have the flicker flam lambency of Svetlanas or the old WE, but they are lucid and have good frequency extension.

I ruined one 300B output tube last night...

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