Author Topic: Tube equivalent (Read 14157 times)

JoeyGS · « **on:** Apr 07, 2012 at 01:49 PM »

What's an equivalent tube for 12AZ7?

I have this in one of my preamp and will be needing a pair for replacement as the readings are now low.

markcrenz · « **Reply #1 on:** Apr 07, 2012 at 03:33 PM »

Quote from: JoeyGS on Apr 07, 2012 at 01:49 PM

What's an equivalent tube for 12AZ7?

I have this in one of my preamp and will be needing a pair for replacement as the readings are now low.

pm mo si tonyt marami daw syang tubes. he might have those or suitable replacements in his small stash, almost 1,000 pcs LANG.

Nelson de Leon · « **Reply #2 on:** Apr 07, 2012 at 05:41 PM »

Quote from: JoeyGS on Apr 07, 2012 at 01:49 PM

What's an equivalent tube for 12AZ7?

I have this in one of my preamp and will be needing a pair for replacement as the readings are now low.

You can also try John Poscablo.

ATJr. · « **Reply #3 on:** Apr 07, 2012 at 06:59 PM »

Quote from: JoeyGS on Apr 07, 2012 at 01:49 PM

What's an equivalent tube for 12AZ7?

I have this in one of my preamp and will be needing a pair for replacement as the readings are now low.

this tube is like a 12at7.....you can get 6201 tubes from gerry sta. maria...+639217430558
you may also want to try 5751 available at Balikbayan handicrafts....
12az7: http://www.shinjo.info/frank/sheets/127/1/12AZ7.pdf
12at7: http://frank.pocnet.net/sheets/093/1/12AT7.pdf

ATJr. · « **Reply #4 on:** Apr 07, 2012 at 07:01 PM »

Quote from: markcrenz on Apr 07, 2012 at 03:33 PM

pm mo si tonyt marami daw syang tubes. he might have those or suitable replacements in his small stash, almost 1,000 pcs LANG.

tutoo yan, but my tube collection is mostly tv power tubes, and transmitter tubes, no audiophile will be interested in my collection....

JoeyGS · « **Reply #5 on:** Apr 07, 2012 at 08:28 PM »

Thanks Tony, Nestor and Matk for the recommendations

JoeyGS · « **Reply #6 on:** Apr 07, 2012 at 08:55 PM »

Would the 5751 be a closer substitute than the 12at7 to the 12az7?

Quote from: TonyT on Apr 07, 2012 at 06:59 PM

this tube is like a 12at7.....you can get 6201 tubes from gerry sta. maria...+639217430558
you may also want to try 5751 available at Balikbayan handicrafts....
12az7: http://www.shinjo.info/frank/sheets/127/1/12AZ7.pdf
12at7: http://frank.pocnet.net/sheets/093/1/12AT7.pdf

rony · « **Reply #7 on:** Apr 07, 2012 at 09:45 PM »

Quote from: JoeyGS on Apr 07, 2012 at 01:49 PM

What's an equivalent tube for 12AZ7?

I have this in one of my preamp and will be needing a pair for replacement as the readings are now low.

My phono preamp uses 12az7, Google the net and it says it can be replaced by 12au7.

btw my preamp is precision fidelity c7.

Nelson de Leon · « **Reply #8 on:** Apr 08, 2012 at 01:18 AM »

Quote from: JoeyGS on Apr 07, 2012 at 08:28 PM

Thanks Tony, Nestor and Matk for the recommendations

Ahem.

ATJr. · « **Reply #9 on:** Apr 08, 2012 at 05:25 AM »

Quote from: JoeyGS on Apr 07, 2012 at 08:55 PM

Would the 5751 be a closer substitute than the 12at7 to the 12az7?

not really close, but can be done.....the 12AZ7 has higher filament current rating, i suspect higher tranconductance than the 12at7/6201........ditto with 5751....

edrel sison · « **Reply #10 on:** Apr 09, 2012 at 09:59 AM »

Preamp tubes:
– 12AX7A / ECC83 / ECC803 / 7025; (high gain – amplification factor = 100)
– 12AD7; (high gain – amplification factor = 100)
– 12AT7 / ECC81; (high gain – amplification factor = 70)
– 12AY7; (med gain – amplification factor = 40)
– 12AU7 / 5814 / 6189 / 5963 / ECC82; (low gain – amplification factor = 17)
– 12AZ7; (med gain – amplification factor = 60)
– 5751; (high gain – amplification factor = 70)

s2kov · « **Reply #11 on:** Apr 10, 2012 at 08:44 PM »

magkano kaya sa Balikbayan handicraft yung 76 driver tube?

Quote from: TonyT on Apr 07, 2012 at 06:59 PM

this tube is like a 12at7.....you can get 6201 tubes from gerry sta. maria...+639217430558
you may also want to try 5751 available at Balikbayan handicrafts....
12az7: http://www.shinjo.info/frank/sheets/127/1/12AZ7.pdf
12at7: http://frank.pocnet.net/sheets/093/1/12AT7.pdf

edrel sison · « **Reply #12 on:** Apr 10, 2012 at 08:47 PM »

1500 list price i think

s2kov · « **Reply #13 on:** Apr 10, 2012 at 08:52 PM »

ok na?

Quote from: edrel sison on Apr 10, 2012 at 08:47 PM

1500 list price i think

alexg · « **Reply #14 on:** Apr 14, 2012 at 01:55 PM »

JoeyGS,

I have a pair of sylvan 12az7 you can try if you are interested. NOS, used for less than 2 hours.

juanbote · « **Reply #15 on:** Apr 21, 2012 at 03:29 PM »

Meron ako sir @ 1.2k pair NOS made in east germany 12AT7 Original boxes.

john poscablo

09228277301

JoeyGS · « **Reply #16 on:** May 04, 2012 at 09:40 AM »

I have a phono preamp, Jolida JD9 and the tubes in the JD-9 are only for the final stage buffer, is it true that gain is not an issue in using other tubes? I plan to tube roll and the current tubes are 12ax7. Will a 12at7 be an acceptable substitute considering that this has a higher transconductance than the 12ax7? What do I expect on the output when I use the 12at7 in this phono preamp?

Quote from: edrel sison on Apr 09, 2012 at 09:59 AM

Preamp tubes:
– 12AX7A / ECC83 / ECC803 / 7025; (high gain – amplification factor = 100)
– 12AD7; (high gain – amplification factor = 100)
– 12AT7 / ECC81; (high gain – amplification factor = 70)
– 12AY7; (med gain – amplification factor = 40)
– 12AU7 / 5814 / 6189 / 5963 / ECC82; (low gain – amplification factor = 17)
– 12AZ7; (med gain – amplification factor = 60)
– 5751; (high gain – amplification factor = 70)

ATJr. · « **Reply #17 on:** May 04, 2012 at 10:50 AM »

^you can try 12at7, gain is a bit lower but you may not notice it....since the circuit was designed and optimized i hope to use the 12ax7, the RIIA equalizations will be upset somewhat since output impedance has changed....

mangboy · « **Reply #18 on:** Jan 13, 2013 at 10:46 PM »

Mga Gurus ano tube equivalent ng ecc99 thanks in advance

JojoD818 · « **Reply #19 on:** Jan 13, 2013 at 10:50 PM »

Quote from: mangboy on Jan 13, 2013 at 10:46 PM

Mga Gurus ano tube equivalent ng ecc99 thanks in advance

Download Duncan's Tube Datasheet Locator here: http://tdsl.duncanamps.com/

mangboy · « **Reply #20 on:** Jan 13, 2013 at 10:51 PM »

Thanks sir jojo!

JojoD818 · « **Reply #21 on:** Jan 13, 2013 at 11:19 PM »

Quote from: mangboy on Jan 13, 2013 at 10:51 PM

Thanks sir jojo!

Welcome po sir!

defcon3 · « **Reply #22 on:** Jan 14, 2013 at 04:29 AM »

hi chief's,

what would be the better replacement for the electron chinese el34b? just recently changed the pre amp tubes to jan philips 12at7 wc.

thanks

meat_eater · « **Reply #23 on:** Jan 14, 2013 at 06:00 AM »

Quote from: defcon3 on Jan 14, 2013 at 04:29 AM

hi chief's,

what would be the better replacement for the electron chinese el34b? just recently changed the pre amp tubes to jan philips 12at7 wc.

thanks

try 6ca7 and nos/current production el34.

brand and era of tubes are subjective by nature as far as sonics are concerned. Experiment talaga, there is no way of knowing without really trying it on sa system mo sir

what sounds good or crap in one might not hold true for your system

ATJr. · « **Reply #24 on:** Jan 14, 2013 at 06:47 AM »

Quote from: mangboy on Jan 13, 2013 at 10:46 PM

Mga Gurus ano tube equivalent ng ecc99 thanks in advance

you can try 12BH7, rewiring the filaments for 6volts, 6GU7, 6FQ7, 6CG7 can be used....

mangboy · « **Reply #25 on:** Jan 14, 2013 at 08:09 AM »

Quote from: TonyT on Jan 14, 2013 at 06:47 AM

you can try 12BH7, rewiring the filaments for 6volts, 6GU7, 6FQ7, 6CG7 can be used....

Thanks sir tony!

JojoD818 · « **Reply #26 on:** Jan 14, 2013 at 10:25 AM »

Quote from: meat_eater on Jan 14, 2013 at 06:00 AM

try 6ca7 and nos/current production el34.

brand and era of tubes are subjective by nature as far as sonics are concerned. Experiment talaga, there is no way of knowing without really trying it on sa system mo sir what sounds good or crap in one might not hold true for your system

6CA7 - fatboys... I have at least 4 quads of these...