Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on May 13, 2011, 07:27:13 am
-
Please add a tube to this list :help:
At flea market sometime you can find NOS cheap tubes, they arent the usual tubes we all remember well, but often they are useable for guitar amp
The purpose of this list is to have a reference as to get when find on the cheap tubes that can be used to build amps
this list is based on my limited knowledge :dontknow:
12ay7
12az7
EL500
EL504
EL509
5879
5654 = Ef905
6ak5 = Ef95
6an8
6an8a
6au6 = Ef84
6bm8 = Ecl82
6gw8 = Ecl86
12dw7 = 7247 = ECC832
EL95 = ½ ell80
6af11
6ac10
12ac10a
6d10
Thanks
Kagliostro
-
ECL80 and ECL82/6U8 (small signal pentode and triode in one bottle)
6P3S (reeeal cheap)
6P3Se (my favourite '5881' at the moment)
6P6 (reeeal cheap 6V6)
6F6G (10W output tube with low input sensitivity - does good at about 300V with an 8k load)
-
QK653
:icon_biggrin:
-
Thanks for adds
Sluckey
QK653
I'm not able to find a data sheet for that tube
which tube is it ?
have you a link for that data sheet or a link to a schematic were that tube is used ?
----
If requested I can post some link to schematics that use many of the tubes I put on the list
Kagliostro
-
1614
1619
1621
1622
4E27A/8001/5-125A
5932
5933
6021
6072
6111
6112
6201
6384
6681
6788
6889
6AB4
6AT6
6AV6
6AY11
6C10
6CA5
6CH6
6CU5
6CW5
6CZ5
6CM6
6DT8
6DY7
6DZ7
6GK6
6HC8
6JB5
6LU8
6Q11
6T10
6U10
7C5
7C7
7EY6
7F7
12BZ7
12DT8
12HL7
-
QK653
:icon_biggrin:
tease!
5.3MW? really?
-
QK653 = Amplitron tube
I think my ears will stop at frequencies slightly lower :icon_biggrin:
Kagliostro
-
DummyLoad
a big list of tubes
are those tubes useables or are tubes that has been used in some amp ?
I'm looking to tubes that were used or can be used as substitution of other more common tubes
I'm not able to plan the use of an "odd" tube like build a champ with a QB3/300
Kagliostro
-
A few more...
12bh7a
ecc99
6ak6
6am5
6ar5
6bl8
7868
6bq6
6jn6
6y6
50c5
-
a big list of tubes...
you asked... :wink:
are those tubes useables or are tubes that has been used in some amp ?
some have - some are tubes i have experimented with or want to experiment with.
I'm looking to tubes that were used or can be used as substitution of other more common tubes
sorry, i did not filter on that criteria. some of them are drop in like 12AZ7, 12DT8, 12BZ7, 6072, 6201, 6681, etc.
--DL
-
5.3MW? really?
Yep. I run mine cool at 4.5MW. Psssh... That's peak power with a duty cycle of 0.00072. Pavg is only about 3.2KW.
-
I think my ears will stop at frequencies slightly lower
Oh you can hear it just fine. Mine is pulsed 360 times per second. Everything in the transmitter room sings that note. Heck, I can sync a scope just with the air! And when the waveguide arcs, you can hear it all over the 2 acre compound. Probably not a good choice for guitar. Forget the roady. You need the whole tractor/trailer!
Sorry, I couldn't help myself...
-
Hi Sluckey
I think you must see this
this is only 50KW but I think that can be enough ..........................
:icon_biggrin: :icon_biggrin: :icon_biggrin: :icon_biggrin:
Kagliostro
-
Well yesterday I was to the Marzaglia (MO - Italy) Radio Amateur Flea Market
and I got a few tube on the cheap (only the Sylvania 5879 was at normal price)
2 x 6201 / JG-12at7 - General Electric NOS (from military stock) - 3.00 each
1 x 12SN7 - Sicte (old Italian Brand) NOS = 1.00
2 x 6ak5 - SFR (old France Brand) NOS = 3.00 each
1 x 6au8 - Westinghouse NOS = 1.00
2 x 12av6 - Thungsram NOS = 3.00 each
2 x 12at7 - Siemens NOS = 3.00 each
1 x 5879 - Sylvania NOS = 10.00
1 x 5879 - RCA NOS = 3.00
1 x 5879 - Branded Tektronix inc = 5.00 (don't think is NOS, it comes in a white box printed only 5879)
3 x 14gw8 - PCL86 - Giant Electronics Brand (???) NOS = 1.00 each
1 x 6ar11 - General Electric NOS = 1.00
any suggestion of use for the 6ar11 compactron tube ????? I got it as it was with other "on the cheap" tubes
:smiley:
Kagliostro
-
any suggestion of use for the 6ar11 compactron tube ?
twin semi-remote cut-off pentode w/ high slope. data-book says it's used as IF amp in TVs.
seems to be of no use. maybe a small P-P amp @ 2.5-3W? don't know if remote cut-off tubes will work in power amp - i'll deffer to the experts.
--DL
-
any suggestion of use for the 6ar11 compactron tube ?
seems to be of no use. maybe a small P-P amp @ 2.5-3W? don't know if remote cut-off tubes will work in power amp - i'll deffer to the experts.
I did try that with a 6AR11 - I can't remember the circuit values, but the output power was minimal, and the crossover distortion horrendous. I too will defer to the experts. :dontknow:
Obviously it could be triode wired as a small signal valve, but there are plenty of twin triodes which would do a better job. :sad:
-
it seems that the 6BN11 would be a better fit. sharp cut-off. similar slope - albeit sightly higher... 12BW11 is a closer match to the AR, but is also a dual sharp cut-off pentode.
i'd bank on the 6LU8 1/2 kind_of_12AT7_like triode and 14W beam pentode w/ moderately high slope ~9500umohs.
something else that looks interesting... the 6AL9 - the pentode is extremely high slope, akin to 8417 yet higher still, but w/ a 10W plate rating in sweep duty. the triode is hi-mu similar characteristics to 1/2 12AT7. without # crunching, i'm thinking a single tube "clean" geetar amp may be possible with <300V B+. i'm thinking however, that one caveat is that pentode could have an achilles heel as the 8417 does - the elements are bound to be very close together to realize such a high slope, and therefor may be fairly prone to arcing...
i think the next "odd ball" amp i put together will be going down the 6LU8 road. AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp. :icon_biggrin:
--DL
oh yeah, add...
6AL9
6FJ7 - compactron similar to 6DR7 (possible reverb driver or triode output amp)
6FM7 - yet another compactron similar to 6DR7.
6FY7 - lower pdiss of above.
6T9 - *very* rare - compactron triode similar to 1/2 12AX7 and pentode is 6V6ish...
-
6T9 - *very* rare - compactron triode similar to 1/2 12AX7 and pentode is 6V6ish...
The 6T10 is far more common. It has the same power pentode as the 6T9, while its "dual control" pentode section can be triode connected. Makes a nice 8-watt push-pull amp . . .
(http://i497.photobucket.com/albums/rr333/valvetone/tio/front.jpg)
-
Thanks for infos
may be is better the 6AR11 rest in my junk box (at 1.00 I can permit myself to get a "wrong" tube)
I'm still collecting spare parts to build the 6AF11 "Squirrel Monkey" amp, results are sure because the project was build and tested
Kagliostro
-
> AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp.
GU81M. 45 Euro (http://www.zeitmann-tubes.com/MilitarySurplus/NosRussianMilitaryTubes/GU81M.htm). Data (http://www.mif.pg.gda.pl/homepages/frank/sheets/018/g/GU81M.pdf)
-
> 6AL9 - the pentode ... a 10W plate rating in sweep duty.
No. VIDEO-amp duty.
Sweep tubes ideally have low dissipation, but when things go wrong, dissipation goes high. They must be specified with a large margin.
A Video Amplifier is a plain class-A amp. It runs hot. It isn't going to get much hotter from minor errors or drift. It is in fact more robust than a transformer-coupled SE audio power amp because the video amp is resistor-loaded and an increase of current makes voltage decrease.
Look at the picture (there's on on eBay today). That plate is not as bg as EL84, maybe 6AQ5. It barely looks like 10W Design Max. The "Typical" condition is 7 Watts dissipation.
It could be a one-bottle small-Champ, ~~3Watts.
-
> AFTER i finish the PRR/ISOdummy 4E27A A1 glo-champ amp.
GU81M. 45 Euro (http://www.zeitmann-tubes.com/MilitarySurplus/NosRussianMilitaryTubes/GU81M.htm). Data (http://www.mif.pg.gda.pl/homepages/frank/sheets/018/g/GU81M.pdf)
no wai jose!
1.2KV Va? that ain't happening + i'm getting much to old to muscle 100# parts around.
maybe if i take up amateur radio as hobby.
45 euros... not a bad price for such a beastly tube.
-
No. VIDEO-amp duty. ....
ack! understood.
don't know why i was thinking vert. sweep & datasheets clearly state VIDEO AMP?
a 3W champ w/ <300V B+ wouldn't be a bad thing. might make a decent first timer build & sockets are still plentiful. maybe throw the 3W at a quirky webber 6x9.
looking at pic on fleabay - at first glance 6AL9 does seem to be a bit on the wimpy side. but from a height/circumference ratio perspective, after a good stare, it does seem to be similar to 6AQ5 in surface area, perhaps a bit less.
--DL
-
GU81M
not sure that those I've seen are exactly that tube, but often at Ham Fest I've seen on sale tube that looks very close to that
at the Radio Amateur flea market in Marzaglia, in 2010, in the ARI (Italian Radio Amateur Association) stand there was an audio amp with one of those big horned tubes without speaker, sound was coming from a plasma flame
Kagliostro
-
6SF5 / 12SF5. Hugh mu single triodes. I have been very happy with the 6SF5s in my most recent build. I think they run about $5 a piece.
-
How about different filament voltages?
You can get NOS tubes that would cost 10x to 20x more IF they were 6.3v heater versions. Filament transformers are cheap in comparison. I have used many of these tubes with excellent results! Most I've found are 50's/60's/70's manufacture, same basic tubes but different heaters.
An added bonus is that as the filament/heater voltage goes up, the current needed to heat them goes down, so smaller rated transformers can be used. For example, a 6L6GA will eat 900mA, but the 19BG6GA only needs 300mA! You can buy a smaller/cheaper filament tranny, PLUS your main PT will run cooler with the lower demand on the 6.3v winding.
EL84/6BQ5 (also 6GK6 already mentioned above) = 10BQ6 (10v), 10GK6 (10v), 16GK6 (16v...$2 each), 29GK6 (29v)
6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)
6L6GA = 19BG6GA (19v)....most places I checked have these for $1 ea
Those are just the few I have used.......
-
> 6SF5 / 12SF5. Hugh mu single triodes. I have been very happy
6F5 is the direct ancestor of 12AX7. 6SF5 is the same without a grid-cap. Same specs. 12AX7 just puts two 6F5 in one smaller bottle with the same total heater demand.
While nominally "same specs", F5 and AX7 are clearly built differently, and as a musician you may hear a difference.
---------------------
> voltage goes up, the current needed to heat them goes down, so smaller rated transformers can be used.
Transformer cost is (should be) proportional to V * A. 6V 0.3A and 12V 0.15A are both 1.8 Watts and both would be wound on a 2VA core and sell at the same price.
True, there's often odd-lots and just odd pricing. 10VA-50VA is often cheap in 24V as excess industrial control parts. Radio Shed used to sell a 2VA, a 4VA, and an 8VA all at the same price (high but not excessive for retail).
-
You should always keep an eye out for the unobtainable 6386.
-
You should always keep an eye out for the unobtainable 6386
NOS NIB $ 249.00
http://cgi.ebay.com/1-NOS-NIB-1959-GE-5-Star-6386-tube-Blk-P-3mica-bent-/270612737987?pt=Vintage_Electronics_R2&hash=item3f01c6afc3 (http://cgi.ebay.com/1-NOS-NIB-1959-GE-5-Star-6386-tube-Blk-P-3mica-bent-/270612737987?pt=Vintage_Electronics_R2&hash=item3f01c6afc3)
yes I must remember that tube when I'm at Ham Fest :icon_biggrin:
Kagliostro
EDIT: I've just read that can be try to substitute the 6386 with a pair of 6BJ6 - 6BA6 triode connected and that tubes are not very expensive - remains the pleasure of the hunt for a rare tube, if found on the cheap .....................
-
Manley makes what's called a "T-Bar" mod that converts a single 9 pin socket to 2 - 7 pin sockets for just such a substitution in their earlier vari-mu compressor. Apparently this tube was only used in a couple of thangs ever, both being compressors. I guess the factories didn't make very many of these. Supposedly JJ is making a reissue and it's like 2 bills as well. Where the rub lies is you need a bunch of matched bottles in parallel, but if you find one for a dollar in a candy dish, it's worth it to flip. Not much use for geetar amps but great fleaBait.
-
How about different filament voltages?
6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)
Or for that matter a 6GW8/ECL86 = 6.3V 700mA filament - the triode is the same as a 1/2 12AX7 and the pentode is similar to an EL84. (i.e.: like a 'more powerful' ECL82)
-
How about different filament voltages?
6BM8/ECL82 = PCL82/16A8 (16v....$6 to $8 ea), UCL82 (50v)
Or for that matter a 6GW8/ECL86 = 6.3V 700mA filament - the triode is the same as a 1/2 12AX7 and the pentode is similar to an EL84. (i.e.: like a 'more powerful' ECL82)
one of my prized finds at hamfests. i designed a guitar amp based around a pair of those not long ago. they are also used in the hammond AO-44 reverb unit and i'm still on the lookout for one that costs less than a good steak. ebayers are wanting insane prices for that stuff now.
another consideration?
6KY8 - 12W BPP & hi-mu triode in a novar pkg. w/ exhaust tip (needs 9 pin sockets w/ a hole in the center). looks kind_of_similar to 6BM8 but g2 slope comes in at lower voltage and max V rating is 150V for g2 - Vg2 would need to be kept in check. triode looks to be similar to 1/2 6SL7. selling about 3-5bux on ebay.
http://tubedata.milbert.com/sheets/049/6/6KY8A.pdf (http://tubedata.milbert.com/sheets/049/6/6KY8A.pdf)
-
Hi DummyLoad
6KY8 a 12W plate dissipation tube - thanks
........... please can you translate BPP ............
BPP = ?? (this day was very hot and hard job so .....................)
Thanks
Kagliostro
-
Beam Power Pentode...
:icon_biggrin:
-
:BangHead: :cussing: :BangHead:
I'm tired ............. I was thinking <B = ????> <PP = Push-Pull> :l2:
thanks
Kagliostro
-
I have got an amplifier with 4 x 807 as end penthode.
Also usable !
-
807
that is a fine tube
also some old Geloso amplifiers used that tubes
that is a well known tube in RF use and also in AF can give good results
Kagliostro
-
I noticed that i have committed another error (in addition to purchasing the 6AR11), thinking to 12AV7 I bought 2 x 12AV6
http://www.nj7p.org/Tube4.php?tube=12AV6 (http://www.nj7p.org/Tube4.php?tube=12AV6)
http://www.nj7p.org/Tube4.php?tube=6AV6 (http://www.nj7p.org/Tube4.php?tube=6AV6)
assuming the double diode section is of no use in guitar amps, what can I do with the triode section of this tubes ?
Can I compare this 12AV6 to a tube of the 12**7 series ? which one ?
Thanks
Kagliostro
-
Can I compare this 12AV6 to a tube of the 12**7 series ? which one ?
6AV6 w/ 12V filaments
1/2 12AX7 ignore the diodes.
--DL
-
1/2 12AX7
That is fine
Thanks
Kagliostro
-
Jojokeo told 6bq6
now I can got some 6bq6gtb on the cheap
(also they are cheap at thetubestore http://thetubestore.com/nos-6bq6.html (http://thetubestore.com/nos-6bq6.html) $ 3.95 each)
what can I do with this tube (BPP <= :icon_biggrin:) ?
which B+ voltage for plates and which OT primary impedance ?
have you schematics of amps using this tube ?
Thanks
Kagliostro
EDIT p.s.: I've read somewere that a PP of 6bq6 can be supply at 320/350v on plates ( ??? ), 150v on screen and 4kohm OT - what about biasing ?
-
A friend want to give me an RCA CRC-6080-WA tube
I've seen only schematics that uses this tube for stabilized power supply
have you never seen an audio use for this tube ??
Thanks
Kagliostro
-
http://www.pmillett.com/file_downloads/ax_lowmu.pdf (http://www.pmillett.com/file_downloads/ax_lowmu.pdf)
-
Thanks DummyLoad
I was thinking a 13W + 13W plate dissipation triode was used for power section not preamp :think1:
Kagliostro
-
http://www.mif.pg.gda.pl/homepages/frank/sheets/164/6/6AS7.pdf (http://www.mif.pg.gda.pl/homepages/frank/sheets/164/6/6AS7.pdf)
-
6AS7 being lo mu has very high drive requirements - usually near the B+ required. this guy in 1949 solves the problem by using 8:1 inter-stage step-up transfo. the design is an unlikely candidate to be a guitar amp.
http://www.bonavolta.ch/hobby/en/audio/6as7_1.htm (http://www.bonavolta.ch/hobby/en/audio/6as7_1.htm)
the best solution would be two supplies - one ~250V high current for the output stage, the second a high voltage (~350-400V) low current for the pre-amp/driver.
looks like use of the 6AS7/6080 wouldn't be very economical or practical.
-
Thanks PRR for the attached link
Thanks DummyLoad for the schematic you posted
http://www.bonavolta.ch/hobby/en/audio/6as7_1.htm
it is interesting to me be because of the way they act the cathode bias of the power tube
as I can see a solution near that I was thinking was used in the past and feasible
http://www.el34world.com/Forum/index.php?topic=11828.0 (http://www.el34world.com/Forum/index.php?topic=11828.0)
looks like use of the 6AS7/6080 wouldn't be very economical or practical
after the explanations I can uderstand and agree with you 6AS7 isn't a tube devoted to guitar amp use
Kagliostro
-
Today I was to another Radio Amatuer Ham Fest
I got an old italian amp (GEM Super Deluxe 50 R) a 11 tube amp two channel with 4 el84 final tubes + reverb and trem
Also I got
2 used 5751 (till now the only 5751 I've seen at flea market, here that tube is not so common)
4 NOS 6005w Siemens tubes
1 used 5687wb tube (seems to be JAN GE)
the seller told me that 6005w is the same of 6aq5 tube (military version)
but I find only datasheet for 6005 tube, not 6005w
can I assume the 6005w and 6aq5 (el90) are the same tube ?
as far I can understanf from a datasheet a PP of 6aq5 needs 250v plate and 10Kohm load (10W out)
what will happen If I use those tube with a PP in an 8Kohm load ?
What about 5687we tube ? in guitar amp is that tube usable and if so, where in the circuit ?
MANY THANKS
Kagliostro
-
I got an old italian amp (GEM Super Deluxe 50 R)
if it's broken, beat it with a prosciutto... just kidding!! nice score! how does it sound?
the seller told me that 6005w is the same of 6aq5 tube (military version)
6005w is 6005/6AQ5/EL90 same tube electrically. they are military - the "W" designation means just that.
what will happen If I use those tube with a PP in an 8Kohm load ?
nothing bad as long as you keep plate dissipation in check.
What about 5687we tube ? in guitar amp is that tube usable
i wouldn't use it as a gain stage, maybe as a reverb driver or a cathodyne. it has a combined plate dissipation of 7.5 watts or 3.75W/section. it seems as though it would likely be a better choice for hi-fi amp or headphone amp use.
-
6AQ5 is a small 6V6. It is fine at 250V 10K load, is over-spec at 6V6's 285V 8K load (but usually works fine).
6005 is a high reliability 6AQ5. The W just means it passes military testing.
If you want 6005W to "never fail" (5,000-10,000 hours), keep it down to 250V. If you want a maximum output hot-rod stage amp, go ahead and hit it with 300V, 350V.
-
MANY THANKS DummyLoad & PRR
so 6005 / 6005W is another tube that can be add to the list of usable tubes
about 5687 i'll use it if I need but don't look to have more
about the amp it isn't in perfect conditions, rats has nibbled some part of the PT outcoming wires
so It must be serviced before to turn on
Kagliostro
-
My mind isn't the same of some years ago, sometime I've little remembering confusions
So, by mistake, thinking to buy a pair of ef40 tubes, I got a pair of ef42 tubes
http://www.r-type.org/pdfs/ef40.pdf (http://www.r-type.org/pdfs/ef40.pdf)
http://www.r-type.org/pdfs/ef42.pdf (http://www.r-type.org/pdfs/ef42.pdf)
are this tubes usable in audio amps ?
Thanks
Kagliostro
-
A new tube to be added to the usable list ??
12fq7
http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/12FQ7.PDF (http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/12FQ7.PDF)
http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/6FQ7.PDF (http://www.tubebooks.org/tubedata/HB-3/Receiving_Tubes_Part_2/6FQ7.PDF)
it is a pin to pin swap with 12a*7 tubes
and if the info I've are correct has a bit more gain than 12au7, however less than 12ax7
what do you think ?
Kagliostro
-
6cg7/6fq7/12fq7 are 6SN7 with down-rating of plate voltage and plate dissipation.
http://www.triodeel.com/rca_c13.gif (http://www.triodeel.com/rca_c13.gif)
i've been fooling around with sub-miniatures lately - 6111 - 6112 - 5639, etc. i use a mill-max 8 pin DIP wire-wrap socket - kind of a rig, but it works.
--DL
-
Kagliostro, did you see the pic of the QK653 I posted in the 'Other Topics' forum? It's been recommended for a nice high power Champ. :icon_biggrin:
-
@ DummyLoad
I've seen some of those little tubes just yesterday, here
http://www.ebay.it/itm/5977-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937164704?pt=Attrezzature_e_strumentazione&hash=item3370e197a0 (http://www.ebay.it/itm/5977-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937164704?pt=Attrezzature_e_strumentazione&hash=item3370e197a0)
http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b (http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b)
http://www.ebay.it/itm/5896-Sylvania-doppio-diodo-lotto-n-10-pezzi-/220937168047?pt=Attrezzature_e_strumentazione&hash=item3370e1a4af (http://www.ebay.it/itm/5896-Sylvania-doppio-diodo-lotto-n-10-pezzi-/220937168047?pt=Attrezzature_e_strumentazione&hash=item3370e1a4af)
If I remember well the "Super Champ" preamp use one of those micro tubes
@ Sluckey
QK653
What a tube ........!
---
which is the gain factor for the 12fq7 ?
http://thetubestore.com/gainfactor.html (http://thetubestore.com/gainfactor.html)
Kagliostro
-
I've just discovered that with an adaptor a 5755 can be used instead of a 12ax7
http://minkara.carview.co.jp/userid/192998/car/80313/2974631/photo.aspx (http://minkara.carview.co.jp/userid/192998/car/80313/2974631/photo.aspx)
only all the text is in japanese and I'm not able to understand well also with the use of a translator
the question is:
compared with 12ax7 which tube is a 5755, a less or a same gain tube ?
(as you know I and datasheet we aren't too friendly)
Kagliostro
-
The 5755 (http://www.mif.pg.gda.pl/homepages/frank/sheets/138/5/5755.pdf) seems largely similar to the 5751.
Compared to the 12AX7, it has somewhat less gain; mu is 70 instead of 100.
Compared to the 5751, it has same mu, higher heater current and high Gm. I am betting the higher Gm is largely due to the higher heater current, with most else being similar to the 5751.
-
much higher plate resistance than a 5751 and an lower anode volt rating. ~140k rp. need to work around that - typical ~1M loads will load the poor little 5755 down.
HBP, i have around 10 sleeves of them and i acquired them for next to nothing - message me if you'd like to give a pair a spin around the block.
best results i've been able to sim so far with what seems like decent headroom, etc., is:
250V = B+
Ra = 100K,
Rk = 2K2,
Ibias ~ 0.66mA,
Vgk ~-1.5V
AV ~28,
Vo ~ 60V pk,
Zo ~55K.
datasheets say tube was designed for low noise instrumentation amp. applications.
seem to have gain similar (a bit less) to that of the 12AY7 with fenderish component values and B+.
--DL
-
Many Thanks HotBluePlates & DummyLoad
Kagliostro
-
I think we have overlooked the obvious 12v6. Available for about five bucks if you look hard enough. I'm building a simple self-split push-pull using two of these. 5F1 simple front end. Edcor PT with 180v HT and 12.6v heater secondary. Cheap, but decent aluminum chassis from ebay. The Edcor OT is 10k, 10W---I hope it's beefy enough.
(http://i155.photobucket.com/albums/s315/spammeup/IMG_2623.jpg)
66merc
-
5992
rare. expensive. bendix red-bank. high-rel 6V6
cool and very rugged looking tube.
--DL
(http://i2.photobucket.com/albums/y11/pmitchel/2012-02-25_06-49-02_260.jpg)
-
12V6 & 5992
OK two other tubes in the list :icon_biggrin:
thanks
Kagliostro
-
If I remember well the "Super Champ" preamp use one of those micro tubes.
it does - the 6948. very nice sounding tube with similar characteristics of the 5751.
much thanks for the ebay.it links. i contacted the seller to see if he'd ship to USA.
http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b#ht_520wt_1163 (http://www.ebay.it/itm/5719-Sylvania-triodo-amplificatrice-lotto-n-10-pezzi-/220937166363?pt=Attrezzature_e_strumentazione&hash=item3370e19e1b#ht_520wt_1163)
we'll see what they say.
grazie!
--DL
-
Yes, they do
Spedizione in: America, Europa, Asia, Australia
only you must ask for expedition price
Ciao
Kagliostro
-
Would say that things are not to be despised, on the contrary
http://jjs.at/electronic/class_a_subminiature.html (http://jjs.at/electronic/class_a_subminiature.html)
(http://jjs.at/electronic/class_a_subminiature_1.png)
http://jjs.at/electronic/class_ab_subminiature.html (http://jjs.at/electronic/class_ab_subminiature.html)
(http://jjs.at/electronic/class_ab_subminiature_1.png)
AB amp samples
Clean (347 kB) - gain at 9 o'clock, strat neck pickup
http://jjs.at/electronic/class_ab_subminiature_clean.mp3 (http://jjs.at/electronic/class_ab_subminiature_clean.mp3)
Distortion (652 kB) - gain at 12 o'clock, strat bridge pickup
http://jjs.at/electronic/class_ab_subminiature_half.mp3 (http://jjs.at/electronic/class_ab_subminiature_half.mp3)
Distortion (839 kB) - full gain, strat bridge pickup
http://jjs.at/electronic/class_ab_subminiature_full.mp3 (http://jjs.at/electronic/class_ab_subminiature_full.mp3)
Were it not for the advent of transistors, today mini tubes would be in all HiFi equipment
The mini tubes we can find were planned to be used in military equipment, so they have a high quality that many of the other tubes haven't
About 6AR11 unfortunately I've a pair but didn't result that they are usable tubes for guitar amp purpose
from the previous page of this tread
any suggestion of use for the 6ar11 compactron tube ?
twin semi-remote cut-off pentode w/ high slope. data-book says it's used as IF amp in TVs.
seems to be of no use. maybe a small P-P amp @ 2.5-3W? don't know if remote cut-off tubes will work in power amp - i'll deffer to the experts.
---
I did try that with a 6AR11 - I can't remember the circuit values, but the output power was minimal, and the crossover distortion horrendous. I too will defer to the experts.
Obviously it could be triode wired as a small signal valve, but there are plenty of twin triodes which would do a better job.
Why build a mini bassman, or tiny twin.
Why many people love things like Ipod :w2:
Kagliostro
-
Let's not forget 829B, a matched power pentode pair in every bottle. I run a pair in the house stereo amp.
Similar to QQV07-40. This tube has been called the most popular VHF tube of all time.
-
Hi Tiny Daddy
This reminds you of something ?
:icon_biggrin: :icon_biggrin: :icon_biggrin:
(http://i.imgur.com/Ze0KfpU.jpg)
Kagliostro
-
Yeah, something... oh, that's my stereo amp! Been running it over 10 years now.
-
One other tube which purpose was to be used as filter in PS
the 6216
(http://i.imgur.com/7zXPCiV.jpg)
http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-PA-5/4.JPG (http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-PA-5/4.JPG)
http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-Bulletin-E-290S/8.JPG (http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-Bulletin-E-290S/8.JPG)
http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/8.JPG (http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/8.JPG)
http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/9.JPG (http://www.wps.com/archives/tube-datasheets/Datasheets/Raytheon-SP-7357-8-61-20M/9.JPG)
someone knows if it was used only for military purpose or also in audio equipments ?
Kagliostro
-
8077/7054 - 5W power pentode cool little tube. 12V heater. g2 is frail.
http://tubedata.milbert.com/sheets/079/8/8077.pdf (http://tubedata.milbert.com/sheets/079/8/8077.pdf)
edit:
added 7061 - interesting lower voltage tube. 10kRa-a PP @ 200V B+ seems workable for about 6W or so. can be had for 5-10 buks.
http://tubedata.milbert.com/sheets/049/7/7061.pdf (http://tubedata.milbert.com/sheets/049/7/7061.pdf)
--DL
-
Interesting tubes
Thanks DL
Kagliostro
-
One more tube
6BE6 an heptode
http://www.retrovox.com.au/6BE6audi.pdf (http://www.retrovox.com.au/6BE6audi.pdf)
http://www.r-type.org/exhib/aaa0011.htm (http://www.r-type.org/exhib/aaa0011.htm)
it was also used by Playmaster in guitar amps as mixer
Kagliostro
-
Kagliostro
Are you building a list that you will share?
Here's my contribution:
6N2P
Its a Russian equivalent to 12ax7 and if you hurry- it is still cheap on eBay
Just a simple heater re- wire
Markus V
-
Are you building a list that you will share?
That is my intention
Ciao
Kagliostro
-
> used by Playmaster in guitar amps as mixer
As a variable-gain amplifier to do tremolo.
(It really does work the same as the RF+LO modulator in a superhetrodyne radio, which IS called a "mixer", but it isn't linear mixing.)
-
Hi PRR
Thanks for your clarification
Can you give a bit further explanation or a link for documentation about ?
As far as I can understand the signal goes to pin #1, the oscillator signal goes to pin #7 (of the 6BE6), the effect is that the signal present on pin #7 change the "gain" of the tube and so there is an AM modulation of the signal present on pin #1 when taken at the plate
I know, my knowledge is poor and my explanation is bad, but this is what I can understand from the circuit (and that may be wrong)
I've never seen other amps using this method, do you think it was advantageous or not ?
Thanks
Kagliostro
-
5814
-
2C52
-
Hi Sluckey & Dummy Load
Many Thanks for adding tubes to the list
Please, about your last two adds (5814 - 2C52), can you briefly indicate which will be a possible use for those tubes ?
Today I recovered a PT from a Sommerkamp FT277 and also I got a 12BY7-A (without the adequate glasses I've read it as a 12BH7), does someone knows if for our purpose (guitar amp & related things) this pentode is usable ?
http://www.r-type.org/pdfs/12by7a.pdf (http://www.r-type.org/pdfs/12by7a.pdf)
Kagliostro
-
2C52 is a 12AX7 in octal envelope with 12.6V ONLY filament and 6SL7 pin-out.
--DL
-
2C52 is a 12AX7 in octal envelope with 12.6V ONLY filament and 6SL7 pin-out.
Thanks DL
that is an useful info ........ and tube
Kagliostro
-
From other theads we can add to the list
6x4 and 6x5 rectifiers for small amps (4W / 5W)
6j5 = 1/2 6sn7
6sq7 = 1/2 12ax7
---
6at6 was present in a previous post but unspecified, it is 1/2 5751
K
-
Also this is a good tube to be added to the list
7c5 = 6v6 but with loctal base
K
-
6F8G - granddad of 12AU7. cool tube - has a grid cap. :-)
--DL
-
Quote from DummyLoad in one other tread
should anyone else have interest in fiddling with 7-pin valves, the 6AB4 is 1/2 of 12AT7, the 6AT6 is 1/2 of 5751, and the 6C4 is 1/2 of 12AU7. there are others but those aforementioned are common still and available at reasonable cost; for time being.... :-\
So as to have also this useful info easily to be find I put it on this tread
6AB4 = 1/2 12AT7
6AT6 = 1/2 5751
6C4 = 1/2 12AU7
K
-
Periodic update of the tread with usable tubes
someone was also previously present in the tread
but here there are reported OT spec & cathode resistor spec
Quote from DummyLoad in one other tread
6AM5 - 4.0W p-p; 250V B+; 24K load; Rk 600R @ 3W
6AR5 - 6.8W p-p; 250V B+; 15K load; Rk 240R @ 3W
6AS5 - 4.4W p-p; 150V B+; 9K load; Rk 1.2K @ 2W
6BF5 - 3.8W p-p; 110V B+; 5K load; Rk 68R @ 2W
6BK5 - 7.0W p-p; 250V B+; 13K load; Rk 68R @ 2W
6CU5 - 4.6W p-p; 120V B+; 5K load; Rk 75R @ 2W
6DS5 - 5.6W p-p; 200V B+; 12K load; Rk 91R @ 2W
6HG5 - 9.0W p-p; 250V B+; 10K load; RK 120R @ 3W <<-- my favorite.
none of the above exceed the the 60mA 1/2 primary rating at full power. the 6HG5 pushes 9W but may do OK but may have weak lo-freq. repro.
considering the hammond has a spec of 8W @ 100Hz. lo-freq down to 50Hz @ 4W seem doable, 70Hz is what most guitar iron is rated at, and likely have a better response overall running 4-6W . the 6AS5 plan seems to be the easiest to implement - 120V PT will get you up around 160V B+ - close enough - run OT @ 10K load - again, close enough.
K
-
Update
Quote from DummyLoad in one other tread (Thanks Pete)
6J7 is closer electrically to 5879 than 6SJ7.
6SJ7 and EF86 are close electrically.
6SH7 and 6AU6 are electrically same.
6J7/6SJ7/6SH7 are all octal except 6J7 has grid cap. i like 6J7, followed close by 6SJ7.
K
-
This seems one other tube that can be add to the list
the E130L (Power Pentode)
http://www.mif.pg.gda.pl/homepages/frank/sheets/009/e/E130L.pdf (http://www.mif.pg.gda.pl/homepages/frank/sheets/009/e/E130L.pdf)
Class AB, 2 tubes in PP = Va 300v | Vg2 150v | Vg1 -17v | Raa 1.6k = 60W
(http://i295.photobucket.com/albums/mm158/electube/MVC-002F-8.jpg?t=1258594489)
what is uncertain is whether it is economically convenient to use it, prices are very different from one seller to one other
http://tubedepot.com/nos-7534.html (http://tubedepot.com/nos-7534.html) = $ 49.95
http://www.thetubestore.com/Tubes/6000-to-9999-Types/7543 (http://www.thetubestore.com/Tubes/6000-to-9999-Types/7543) = $ 6.95
My fault the second link is about 7543 not 7534 :worthy1:
K
-
Two other tubes for the list
6bw6 = a 6v6 in a 9 pin bottle
http://www.r-type.org/pdfs/6bw6.pdf (http://www.r-type.org/pdfs/6bw6.pdf)
http://www.r-type.org/exhib/aaa0343.htm (http://www.r-type.org/exhib/aaa0343.htm)
6br7 a small low noise pentode
http://www.r-type.org/pdfs/6br7.pdf (http://www.r-type.org/pdfs/6br7.pdf)
http://www.r-type.org/exhib/aaa0346.htm (http://www.r-type.org/exhib/aaa0346.htm)
K
-
One other tube
the QE08/200
http://www.mif.pg.gda.pl/homepages/frank/sheets/030/q/QE08-200.pdf (http://www.mif.pg.gda.pl/homepages/frank/sheets/030/q/QE08-200.pdf)
this monster tube here compared with KT88 and EL34
(http://i.imgur.com/tO5P1wd.jpg)
was used by Philips in one of his audio amp, the EV4418
(http://i.imgur.com/GE6ufFT.jpg)
(http://i.imgur.com/g44NVlK.jpg)
K
-
I've been playing with the 6J6, 2 nos, 2 new, in 3 different circuits and all the tubes are micro-phonic. Is that normal with 6J6?
-
I'm not sure I understand whether this is a list of known-useful tubes, or just bargains...
Hopefully this fits:
I just bought some odd NOS ones.
8 x RCA 5964. Dual triode with common cathode, 7-pin mini, typ. mu = 39, gm=6000 uS, similar to 6J6? $17.95 shipped
5 x Dumont/ERP 7060. medium mu (40?) triode + small power pentode (2.75 W anode diss. max.), 9-pin mini, 12-15 V filament (13.2 nominal, mobile use originally) $7.95 shipped
I'll do some reading and spreadsheeting before asking how to make use of the 7060's
-
5964 is common-cathode which is awkward in most guitar amp stages. Aimed for much higher current than we usually need for audio. Yeah, probably a 6J6 with new data and name.
7060 is a fine filler for complex systems like a TV set. 12V heater is not common in guitar amp builds. As a power stage it is barely over 1W, and that at awkwardly low B+ (say 150-200V). The triode is again a high-current lowish gain job. Both together do not make a sparkling mini-amp for guitar.
-
I've been playing with the 6J6, 2 nos, 2 new, in 3 different circuits and all the tubes are micro-phonic. Is that normal with 6J6?
IME, yes. there are some commercial/industrial/military variants that may perform better in audio but i haven't tested any. list below. the 7244 looks promising: has stacked ceramic spacers so should be more rigid.
5844
5964
6045
6101
7244
7244-A
--pete
-
6J6 makes a fine LTPI or bonded single stage - e.g. use as single triode.
--pete
-
Cool Pete :thumbsup:
I've some of those tubes
Franco
-
6cz5 amazing American tone.(10bucks nos)
Just like a 6973. Like a 6v6 except handle higher voltage.
Also 5v 5cz5 (2bucks )