Guide to buying 12ax7 tubes

oracle1974

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Hi
I am new to tubes and wish to procure one of the following 12ax7 tubes:

1. Amperex Bugle Boy
2. Mazda Silver Plate Triple Mica or 2 Mica
3. Siemens Long Plate

Let me know the best way to get these tubes. www.audiotubes.com is the recommended website for procuring these tubes.
What are the other options?

Thank you in anticipation.
 
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Hi
I am new to tubes and wish to procure one of the following 12ax7 tubes:

1. Amperex Bugle Boy
2. Mazda Silver Plate Triple Mica or 2 Mica
3. Siemens Long Plate

Let me know the best way to get these tubes. www.audiotubes.com is the recommended website for procuring these tubes.
What are the other options?

Thank you in anticipation.
Hi

I have sourced many tubes from Brent Jesse. Very reliable. Buy blindly.

Sound signatures of the tubes are described well by Brent on his site. Go by what he says.

Here's my two paisa. (I have had most of the models he carries in the 12au7 flavor which is a low gain 12ax7). All tubes take 50 to 100 hours to burn in. Don't judge it till then. Usually whatever you feel is lacking will fill in with burn in.

1. The best tube is the Telefunken smooth plate. Eventually you will come back to this tube. It extends fully, very clean. Like looking out of a thick pane of very clean glass. It isn't lean yet has no fat.

2. Amperex - be careful. They have a million models. From experience anything below 150 usd sounds too fuzzy. The 1950s d getters are superb. But amperex is too fuzzy overall. You will like the added harmonics but eventually you'll get bored of the fuzz.

3. Mazda - I haven't tried the chrome or nickel plates but the entry level one that I tried was like thermocol sounding. Buy the Telefunken instead.

4. Siemens - ive never had good luck with siemens. If you must buy them go with the 1960s or earlier. They are like the Telefunken but have a larger image. I find the image smearing everything else. But it may work if your equip extends to deliver a very thin sound.

5. Mullard - sounds like mush. Again I've only tried the lower end model. But it has no edge to it. It's like everything has no borders only mushiness.

6. Sylvania - the gold brand take forever to burn in. They are dry sounding and have a slight suck out and nasalness in the mids. However the dry sound can sound lovely if you want your system to sound like old school vinyl.

7. GE - very neutral tube but doesn't have any highs or lows. Probably has the most natural male vocal but the lack of highs kills any appeal. Again in the right system it can be superb especially if the setup has a tendency to deliver a V shaped sound. In my setup which already tends to the warm side it sounds too damped. In a faster system I can see it delivering though.
 
Audiopro, thanks for the detailed explanation. My intent is to replace the Chinese stock tubes. The recommendation on forums is to replace the stock tubes with Mazda Chrome plate or Siemens long plates. Amperex Bugle Boy d getters and telefunken are also highly recommended. Your caveat on the Amperex probably explains why it is not the most preferred tube. Thanks for this insight.

The siemens long plate that Brent Jessee has in stock is being recommended over the telefunken. It is also cheaper than the Mazda chrome plate and that makes me leaning towards it. Mazda can wait for some other time.

I am not in a hurry though as my current Tube DAC is less than 20 hours burnt in. And even stock tubes with adequate burn in will show some more improvement.

I am enjoying what I am hearing and this post is motivated by our shared perennial bug "what more can I get out of my system".

Thanks again!
 
Audiopro, thanks for the detailed explanation. My intent is to replace the Chinese stock tubes. The recommendation on forums is to replace the stock tubes with Mazda Chrome plate or Siemens long plates. Amperex Bugle Boy d getters and telefunken are also highly recommended. Your caveat on the Amperex probably explains why it is not the most preferred tube. Thanks for this insight.

The siemens long plate that Brent Jessee has in stock is being recommended over the telefunken. It is also cheaper than the Mazda chrome plate and that makes me leaning towards it. Mazda can wait for some other time.

I am not in a hurry though as my current Tube DAC is less than 20 hours burnt in. And even stock tubes with adequate burn in will show some more improvement.

I am enjoying what I am hearing and this post is motivated by our shared perennial bug "what more can I get out of my system".

Thanks again!

What dac are you using? And which way are you looking at taking the system? Please note that tube dacs are usually capacitor coupled. Which means they have a high output impedence which in turn needs the receiving amplifier to have a high input impedence of atleast 50k ohms if not 100k. If your finding the system balance completely off or too thin n lifeless then this could be a problem.

I have tried new Russian tubes from sovtek etc. They are ok. Just OK. Like little worse or equal to the cheapest amperex. They tend to be too thick n muddy. Like someone condensed to water on the glass pane.

Psvane is another decent tube manufacturer. If you have heard the focal Electra speaker with the beryllium tweeter you'll understand the psvane signature. It has a very delicate top end and the mids n bass are clean yet sweet. This grabs you initially but after sometime everything sounds like Eva Cassidy and you learn to respect the mighty telefunken smooth plate. If your getting siemens go with the top notch 1960s and before stuff or you'll be severely disappointed.

What's the dac and rest of the system like? I feel the Chinese tubes won't sing even after opening up. New tubes don't breathe easily. It's like someone is talking behind a curtain. U can't feel the music set free.
 
Thanks again.
My system:

Accustic Arts Reference Drive 2 connected to
Accustic Arts Tube DAC 2 by Sablon Audio Panatela AES XLR cable
Accustic Arts Power 1 Mk3 (integrated)
Gauder Akustik Vescova mk 2 speakers.

The system is sounding fine. My earlier source was Accustic Arts CD Player. On a relative terms, there is a significant improvement.

If the Chinese stock tubes are never going to open up, then I may as well as is recommended by most is to change the stock tubes as soon as possible.
 
Thanks again.
My system:

Accustic Arts Reference Drive 2 connected to
Accustic Arts Tube DAC 2 by Sablon Audio Panatela AES XLR cable
Accustic Arts Power 1 Mk3 (integrated)
Gauder Akustik Vescova mk 2 speakers.

The system is sounding fine. My earlier source was Accustic Arts CD Player. On a relative terms, there is a significant improvement.

If the Chinese stock tubes are never going to open up, then I may as well as is recommended by most is to change the stock tubes as soon as possible.

Very nicely done setup. Especially maintaining one brand for all the electronics. Kudos.

The dac has a low output impedence as it is a hybrid. So theres no problem with matching there.
I have plpayed around with the BB627 opamps in the past and base don their sound signature I would stay away from
the Amperex tubes for sure. I still feel a Telefunken 12AX7 smooth plate would be the best match because it doesn't act smart
and overdo anything which you then have to again compensate down the chai;. hence it is left to your system placement etc to do whatever fine changes you desire.

Your speaker is a ceramic based one. I have never heard this speaker but if it sounds a little thin or lean then the Siemens may
balance that out. Remember the Siemens fattens the mids. Brent Jesse refers this as liquidity and I never understood that term till
I got the tube. Its fatter but clean. Like changing a solid glass pane into as transparent a jelly. You may feel it to be harmonically richer than the Tele but that isn't the case. It just bloats the mids out (while retaining the transparency) and hence makes those harmonics sound thicker as well.

The AA page says they are using selected military tubes. I doubt these are chinese tubes if that's the case. Most likely JAN NOS from Sylvania or GE tubes. Those arn't great tubes either! Little harsh sounding in the highs.
 
Oracle1974, audiopro is the resident 12ax7 tube expert :)

For my EAR 834 phono, I was recommended the Telefunken smooth plate. I like the sound.

For my LTA Ultralinear amp, I have been recommended the Amperex Bugle Boy by the manufacturer over the Telefunken. So am going ahead with the recommendation. Haven’t received the amp as yet. So don’t have an opinion as yet.

What I wanted to point out was, there may not be one brand of tube that works in all pieces of equipment.

The Telefunken is very neutral and I like that kind of sound. The Bugle Boy is a richer sounding tube, not necessarily neutral, as per reports I have read. Maybe the Ultralinear amp needs that touch of richness.

These tubes are expensive. So don’t buy blind. See if you can hear them someplace and form your own opinion before taking the plunge.
 
Very nicely done setup. Especially maintaining one brand for all the electronics. Kudos.

The dac has a low output impedence as it is a hybrid. So theres no problem with matching there.
I have plpayed around with the BB627 opamps in the past and base don their sound signature I would stay away from
the Amperex tubes for sure. I still feel a Telefunken 12AX7 smooth plate would be the best match because it doesn't act smart
and overdo anything which you then have to again compensate down the chai;. hence it is left to your system placement etc to do whatever fine changes you desire.

Your speaker is a ceramic based one. I have never heard this speaker but if it sounds a little thin or lean then the Siemens may
balance that out. Remember the Siemens fattens the mids. Brent Jesse refers this as liquidity and I never understood that term till
I got the tube. Its fatter but clean. Like changing a solid glass pane into as transparent a jelly. You may feel it to be harmonically richer than the Tele but that isn't the case. It just bloats the mids out (while retaining the transparency) and hence makes those harmonics sound thicker as well.

The AA page says they are using selected military tubes. I doubt these are chinese tubes if that's the case. Most likely JAN NOS from Sylvania or GE tubes. Those arn't great tubes either! Little harsh sounding in the highs.
Thanks again.

AA page will refer to the latest version of DAC while I have the earlier version which has the Chinese stock tubes.

Thanks for the elaborate explanation and it is definitely guiding me to take a more informed decision. I shall look at the Telefunken.
 
Oracle1974, audiopro is the resident 12ax7 tube expert :)

Yes totally agree with you, a full time resident expert and his metaphors are excellent and make things a lot more crystal clear.

For my EAR 834 phono, I was recommended the Telefunken smooth plate. I like the sound.

For my LTA Ultralinear amp, I have been recommended the Amperex Bugle Boy by the manufacturer over the Telefunken. So am going ahead with the recommendation. Haven’t received the amp as yet. So don’t have an opinion as yet.

What I wanted to point out was, there may not be one brand of tube that works in all pieces of equipment.

The Telefunken is very neutral and I like that kind of sound. The Bugle Boy is a richer sounding tube, not necessarily neutral, as per reports I have read. Maybe the Ultralinear amp needs that touch of richness.

These tubes are expensive. So don’t buy blind. See if you can hear them someplace and form your own opinion before taking the plunge.

Thanks for the recommendation and cautionary advice.
 
Hi, one question how different or better are military tubes over non-military tubes?
Thanks

Different NOT better. They were built to be more rugged and reliable. But they were made for performing to their specs under various conditions. Not for audio or communication purpose. It is just that the military had to keep a large stock as they don't phase out equipment just because tubes are not in vogue. However post the 80s-90s a lot of military stock is being sold off and hence you have a large availability of JAN tubes at good prices. Sound wise they are an in between unless you get some Bendix which needs convertors as their pin mapping tends to be different. They however make output and rectifier tubes only from what I know. Maybe an odd preamp tube here n there.

Don't expect JAN tubes to last longer. It all depends on how hard your amp uses them. They may have less microphonics due to the rugged structure (usually more support plates within the tube). Google the bendix 6094 to get a read on the best built military tube. Uses pyrex glass to handle the heat. I use them in my amp:)
 
I am deciding to go for Mazda Silver plate tubes as users of the DAC have recommended it over others.
Am getting the non-military version and will place an order for those.
Thanks for all the prompt guidance.
 
I am deciding to go for Mazda Silver plate tubes as users of the DAC have recommended it over others.
Am getting the non-military version and will place an order for those.
Thanks for all the prompt guidance.

Say hello to Brent for me.
 
Hi everybody,
I am new to tubes too and considering importing tubes from Brent, as per suggestion of Audiopro. Just wanted to know whether i would be charged any custom duty on it. Oracle1974, kindly excuse me from posting this question in your thread. Hope the knowledgeable audiophiles can provide this information.
 
The customs duty will be applied on the value declared. If you ask the seller to declare a lower value, you will not get the benefit of insurance if the item is lost in transit or gets damaged in transit.
If you declare a lower value say less $50 it will probably escape customs scrutiny but the attendant risks as highlighted above will remain.
Hope this clarifies.
 
Thanks for the explanation. Do you know whether tubes are classified as electrical or electronic parts and the rate charged for customs on them?
 
Always on the safer side I assume the duty to be 42.2%. Explaining to customs officials always remains a challenge and requires a lot of patience and time.
 
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