I have a Fender reissue model guitar amp in for service. It has 2 Fender 12AX7's that are microphonic. These are Chinese manufacture. I have replaced them with 5814's which is some sort of 12AU7 type just to get the amp working. There is no more microphonic problem, however the amplifier sensitivity is now somewhat lower so perhaps that may have a bearing on this. I realise that I have no 12AX7's in the shop at all and would like to buy several, two for this amplifier and two or three for stock. I was looking at NOS and JAN types online and would like to go with either but I suffered real sticker shock when I noticed the prices. I don't have much faith in the Russian or Chinese tubes so I was hoping that someone could offer some advice as to a source for good preamp tubes either new or tested used, and ones that I don't have to worry about microphonics. Thanks, Lenny.
>I have a Fender reissue model guitar amp in for service. It has 2 > Fender 12AX7's that are microphonic. These are Chinese manufacture. I > have replaced them with 5814's which is some sort of 12AU7 type just > to get the amp working. There is no more microphonic problem, however > the amplifier sensitivity is now somewhat lower so perhaps that may > have a bearing on this. I realise that I have no 12AX7's in the shop > at all and would like to buy several, two for this amplifier and two > or three for stock. I was looking at NOS and JAN types online and > would like to go with either but I suffered real sticker shock when I > noticed the prices. I don't have much faith in the Russian or Chinese > tubes so I was hoping that someone could offer some advice as to a > source for good preamp tubes either new or tested used, and ones that > I don't have to worry about microphonics. Thanks, Lenny.
I've had some complete junk Chinese tubes, e.g. power output pentodes that burned the cathode resistors on the first use due to internal shorts. I've had good luck with Russian tubes however, the Svetlana ones seem to be very good but you must make sure they're the St.Petersburg manufactured ones and not the Sovtek ones; see the bottom of this page for more information: http://www.amp-fix.com/biasing%5B1%5D.htm Martin -- martin<dot here>whybrow<at here>ntlworld<dot here>com
captainvideo462...@yahoo.com wrote: > I have a Fender reissue model guitar amp in for service. It has 2 > Fender 12AX7's that are microphonic. These are Chinese manufacture. I > have replaced them with 5814's which is some sort of 12AU7 type just > to get the amp working. There is no more microphonic problem, however > the amplifier sensitivity is now somewhat lower so perhaps that may > have a bearing on this. I realise that I have no 12AX7's in the shop > at all and would like to buy several, two for this amplifier and two > or three for stock. I was looking at NOS and JAN types online and > would like to go with either but I suffered real sticker shock when I > noticed the prices. I don't have much faith in the Russian or Chinese > tubes so I was hoping that someone could offer some advice as to a > source for good preamp tubes either new or tested used, and ones that > I don't have to worry about microphonics. Thanks, Lenny.
Dave,
I've had good success with the JJ/Tesla tubes (from Slovakia as I recall) They usually run around $10-15 each. One vendor that has them is Antique Electronic Supply (www.tubesandmore.com). They have various grades of the things. I'm speaking form a standpoint of reliability. We could have an endless discussion (and tread) about the sound quality of various tubes which I'd rather avoid.
>I have a Fender reissue model guitar amp in for service. It has 2 > Fender 12AX7's that are microphonic. These are Chinese manufacture. I > have replaced them with 5814's which is some sort of 12AU7 type just > to get the amp working. There is no more microphonic problem, however > the amplifier sensitivity is now somewhat lower so perhaps that may > have a bearing on this. I realise that I have no 12AX7's in the shop > at all and would like to buy several, two for this amplifier and two > or three for stock. I was looking at NOS and JAN types online and > would like to go with either but I suffered real sticker shock when I > noticed the prices. I don't have much faith in the Russian or Chinese > tubes so I was hoping that someone could offer some advice as to a > source for good preamp tubes either new or tested used, and ones that > I don't have to worry about microphonics. Thanks, Lenny.
The shop that I do a lot of work for uses many Russian tubes, and I have, in general, not found them to be a problem either reliability, spec or microphony wise. Brands that he stocks are, for instance, Ruby and Electro Harmonix. Do you have a music shop in your area ? They all stock replacement tubes over here, so I guess they would there too. Genuine Fender supplied tubes are not all that expensive, and likewise, Marshalls. However, preamp tubes such as 12AX7 do tend to come in quality levels. For instance, some of the 12AX7s that this particular shop stocks, are specced as "Premium Grade" and retail for 21 GBP (around $33) each, although obviously not that much to buy trade ...
> >I have a Fender reissue model guitar amp in for service. It has 2 > > Fender 12AX7's that are microphonic. These are Chinese manufacture. I > > have replaced them with 5814's which is some sort of 12AU7 type just > > to get the amp working. There is no more microphonic problem, however > > the amplifier sensitivity is now somewhat lower so perhaps that may > > have a bearing on this. I realise that I have no 12AX7's in the shop > > at all and would like to buy several, two for this amplifier and two > > or three for stock. I was looking at NOS and JAN types online and > > would like to go with either but I suffered real sticker shock when I > > noticed the prices. I don't have much faith in the Russian or Chinese > > tubes so I was hoping that someone could offer some advice as to a > > source for good preamp tubes either new or tested used, and ones that > > I don't have to worry about microphonics. Thanks, Lenny.
> The shop that I do a lot of work for uses many Russian tubes, and I have, in > general, not found them to be a problem either reliability, spec or > microphony wise. Brands that he stocks are, for instance, Ruby and Electro > Harmonix. Do you have a music shop in your area ? They all stock replacement > tubes over here, so I guess they would there too. Genuine Fender supplied > tubes are not all that expensive, and likewise, Marshalls. However, preamp > tubes such as 12AX7 do tend to come in quality levels. For instance, some of > the 12AX7s that this particular shop stocks, are specced as "Premium Grade" > and retail for 21 GBP (around $33) each, although obviously not that much to > buy trade ...
> Arfa
I've heard good things about Electro Harmonix from other people too. Maybe I'll try some of these. Thanks, Lenny
> >I have a Fender reissue model guitar amp in for service. It has 2 > > Fender 12AX7's that are microphonic. These are Chinese manufacture. I > > have replaced them with 5814's which is some sort of 12AU7 type just > > to get the amp working. There is no more microphonic problem, however > > the amplifier sensitivity is now somewhat lower so perhaps that may > > have a bearing on this. I realise that I have no 12AX7's in the shop > > at all and would like to buy several, two for this amplifier and two > > or three for stock. I was looking at NOS and JAN types online and > > would like to go with either but I suffered real sticker shock when I > > noticed the prices. I don't have much faith in the Russian or Chinese > > tubes so I was hoping that someone could offer some advice as to a > > source for good preamp tubes either new or tested used, and ones that > > I don't have to worry about microphonics. Thanks, Lenny.
> The shop that I do a lot of work for uses many Russian tubes, and I have, > in > general, not found them to be a problem either reliability, spec or > microphony wise. Brands that he stocks are, for instance, Ruby and Electro > Harmonix. Do you have a music shop in your area ? They all stock > replacement > tubes over here, so I guess they would there too. Genuine Fender supplied > tubes are not all that expensive, and likewise, Marshalls. However, preamp > tubes such as 12AX7 do tend to come in quality levels. For instance, some > of > the 12AX7s that this particular shop stocks, are specced as "Premium > Grade" > and retail for 21 GBP (around $33) each, although obviously not that much > to > buy trade ...
> Arfa
I've heard good things about Electro Harmonix from other people too. Maybe I'll try some of these. Thanks, Lenny
I've certainly not had a problem with them, Lenny, and my friend's shop sells quite a lot of them as 'general' customer replacements. Matching does seem to have been done by them with some care, on output tubes that are sold as being a matched pair or quad.
>>> I have a Fender reissue model guitar amp in for service. It has 2 >>> Fender 12AX7's that are microphonic. These are Chinese manufacture. I >>> have replaced them with 5814's which is some sort of 12AU7 type just >>> to get the amp working. There is no more microphonic problem, however >>> the amplifier sensitivity is now somewhat lower so perhaps that may >>> have a bearing on this. I realise that I have no 12AX7's in the shop >>> at all and would like to buy several, two for this amplifier and two >>> or three for stock. I was looking at NOS and JAN types online and >>> would like to go with either but I suffered real sticker shock when I >>> noticed the prices. I don't have much faith in the Russian or Chinese >>> tubes so I was hoping that someone could offer some advice as to a >>> source for good preamp tubes either new or tested used, and ones that >>> I don't have to worry about microphonics. Thanks, Lenny. >> The shop that I do a lot of work for uses many Russian tubes, and I have, >> in >> general, not found them to be a problem either reliability, spec or >> microphony wise. Brands that he stocks are, for instance, Ruby and Electro >> Harmonix. Do you have a music shop in your area ? They all stock >> replacement >> tubes over here, so I guess they would there too. Genuine Fender supplied >> tubes are not all that expensive, and likewise, Marshalls. However, preamp >> tubes such as 12AX7 do tend to come in quality levels. For instance, some >> of >> the 12AX7s that this particular shop stocks, are specced as "Premium >> Grade" >> and retail for 21 GBP (around $33) each, although obviously not that much >> to >> buy trade ...
>> Arfa
> I've heard good things about Electro Harmonix from other people too. > Maybe I'll try some of these. Thanks, Lenny
> I've certainly not had a problem with them, Lenny, and my friend's shop > sells quite a lot of them as 'general' customer replacements. Matching does > seem to have been done by them with some care, on output tubes that are sold > as being a matched pair or quad.
> Arfa
Good morning all,
I'll have to disagree with at least SOME of the Electro Harmonix tubes. I've had nothing but grief with their 7591's. Bias drifting all over the place, and in one case trashing an output transformer.
><captainvideo462...@yahoo.com> wrote in message >news:3c177e12-0103-4c13-9001-9b151e157cd2@l2g2000yqd.googlegroups.com... >>I have a Fender reissue model guitar amp in for service. It has 2 >> Fender 12AX7's that are microphonic. These are Chinese manufacture. I >> have replaced them with 5814's which is some sort of 12AU7 type just >> to get the amp working. There is no more microphonic problem, however >> the amplifier sensitivity is now somewhat lower so perhaps that may >> have a bearing on this. I realise that I have no 12AX7's in the shop >> at all and would like to buy several, two for this amplifier and two >> or three for stock. I was looking at NOS and JAN types online and >> would like to go with either but I suffered real sticker shock when I >> noticed the prices. I don't have much faith in the Russian or Chinese >> tubes so I was hoping that someone could offer some advice as to a >> source for good preamp tubes either new or tested used, and ones that >> I don't have to worry about microphonics. Thanks, Lenny.
>The shop that I do a lot of work for uses many Russian tubes, and I have, in >general, not found them to be a problem either reliability, spec or >microphony wise. Brands that he stocks are, for instance, Ruby and Electro >Harmonix. Do you have a music shop in your area ? They all stock replacement >tubes over here, so I guess they would there too. Genuine Fender supplied >tubes are not all that expensive, and likewise, Marshalls. However, preamp >tubes such as 12AX7 do tend to come in quality levels. For instance, some of >the 12AX7s that this particular shop stocks, are specced as "Premium Grade" >and retail for 21 GBP (around $33) each, although obviously not that much to >buy trade ...
>Arfa
I've found the new Electro Harmonix dual triodes like the AX7, 83, etc.. to become microphonic more often than the better Ruskie tubes from Winged C. When it has to be uber reliable and the cust wants to spend the extra $$ we still rely on NOS from Philips. I just repaired an Ampeg SVT 3 hybrid, FET outs, tubes in the tone holes. Electro Harmonix the cust changed himself back in July. He wouldn't go for the NOS tubes so we put what he wanted back in the EH.s. I told him to keep the amp off the speaker cabinet or it would shake them loose inside again prematurely.
> On Tue, 17 Nov 2009 01:42:02 -0000, "Arfa Daily" > <arfa.da...@ntlworld.com>wrote:
>><captainvideo462...@yahoo.com> wrote in message >>news:3c177e12-0103-4c13-9001-9b151e157cd2@l2g2000yqd.googlegroups.com... >>>I have a Fender reissue model guitar amp in for service. It has 2 >>> Fender 12AX7's that are microphonic. These are Chinese manufacture. I >>> have replaced them with 5814's which is some sort of 12AU7 type just >>> to get the amp working. There is no more microphonic problem, however >>> the amplifier sensitivity is now somewhat lower so perhaps that may >>> have a bearing on this. I realise that I have no 12AX7's in the shop >>> at all and would like to buy several, two for this amplifier and two >>> or three for stock. I was looking at NOS and JAN types online and >>> would like to go with either but I suffered real sticker shock when I >>> noticed the prices. I don't have much faith in the Russian or Chinese >>> tubes so I was hoping that someone could offer some advice as to a >>> source for good preamp tubes either new or tested used, and ones that >>> I don't have to worry about microphonics. Thanks, Lenny.
>>The shop that I do a lot of work for uses many Russian tubes, and I have, >>in >>general, not found them to be a problem either reliability, spec or >>microphony wise. Brands that he stocks are, for instance, Ruby and Electro >>Harmonix. Do you have a music shop in your area ? They all stock >>replacement >>tubes over here, so I guess they would there too. Genuine Fender supplied >>tubes are not all that expensive, and likewise, Marshalls. However, preamp >>tubes such as 12AX7 do tend to come in quality levels. For instance, some >>of >>the 12AX7s that this particular shop stocks, are specced as "Premium >>Grade" >>and retail for 21 GBP (around $33) each, although obviously not that much >>to >>buy trade ...
>>Arfa
> I've found the new Electro Harmonix dual triodes like the AX7, 83, > etc.. to become microphonic more often than the better Ruskie tubes > from Winged C. When it has to be uber reliable and the cust wants to > spend the extra $$ we still rely on NOS from Philips. I just repaired > an Ampeg SVT 3 hybrid, FET outs, tubes in the tone holes. Electro > Harmonix the cust changed himself back in July. He wouldn't go for the > NOS tubes so we put what he wanted back in the EH.s. I told him to > keep the amp off the speaker cabinet or it would shake them loose > inside again prematurely.
Hmmm. That's odd. I can't honestly say that I've had any particular problems with EH tubes. I have to say that most of the ones that my friend stocks in his shop are Ruby brand, but a fair few are EH, and he's not the sort of bloke to continue stocking a product that was giving him any trouble. Apart from anything else, he's a muso himself, who has been in the sales / repair / hire business for this sort of kit, for many many years. Interestingly though, Rubys *are* made in China ... They are available in the U.S. see
>"Meat Plow" <m...@petitmorte.net> wrote in message >news:39rhpe.rec.17.3@news.alt.net... >> On Tue, 17 Nov 2009 01:42:02 -0000, "Arfa Daily" >> <arfa.da...@ntlworld.com>wrote:
>>><captainvideo462...@yahoo.com> wrote in message >>>news:3c177e12-0103-4c13-9001-9b151e157cd2@l2g2000yqd.googlegroups.com... >>>>I have a Fender reissue model guitar amp in for service. It has 2 >>>> Fender 12AX7's that are microphonic. These are Chinese manufacture. I >>>> have replaced them with 5814's which is some sort of 12AU7 type just >>>> to get the amp working. There is no more microphonic problem, however >>>> the amplifier sensitivity is now somewhat lower so perhaps that may >>>> have a bearing on this. I realise that I have no 12AX7's in the shop >>>> at all and would like to buy several, two for this amplifier and two >>>> or three for stock. I was looking at NOS and JAN types online and >>>> would like to go with either but I suffered real sticker shock when I >>>> noticed the prices. I don't have much faith in the Russian or Chinese >>>> tubes so I was hoping that someone could offer some advice as to a >>>> source for good preamp tubes either new or tested used, and ones that >>>> I don't have to worry about microphonics. Thanks, Lenny.
>>>The shop that I do a lot of work for uses many Russian tubes, and I have, >>>in >>>general, not found them to be a problem either reliability, spec or >>>microphony wise. Brands that he stocks are, for instance, Ruby and Electro >>>Harmonix. Do you have a music shop in your area ? They all stock >>>replacement >>>tubes over here, so I guess they would there too. Genuine Fender supplied >>>tubes are not all that expensive, and likewise, Marshalls. However, preamp >>>tubes such as 12AX7 do tend to come in quality levels. For instance, some >>>of >>>the 12AX7s that this particular shop stocks, are specced as "Premium >>>Grade" >>>and retail for 21 GBP (around $33) each, although obviously not that much >>>to >>>buy trade ...
>>>Arfa
>> I've found the new Electro Harmonix dual triodes like the AX7, 83, >> etc.. to become microphonic more often than the better Ruskie tubes >> from Winged C. When it has to be uber reliable and the cust wants to >> spend the extra $$ we still rely on NOS from Philips. I just repaired >> an Ampeg SVT 3 hybrid, FET outs, tubes in the tone holes. Electro >> Harmonix the cust changed himself back in July. He wouldn't go for the >> NOS tubes so we put what he wanted back in the EH.s. I told him to >> keep the amp off the speaker cabinet or it would shake them loose >> inside again prematurely.
>Hmmm. That's odd. I can't honestly say that I've had any particular problems >with EH tubes. I have to say that most of the ones that my friend stocks in >his shop are Ruby brand, but a fair few are EH, and he's not the sort of >bloke to continue stocking a product that was giving him any trouble. Apart >from anything else, he's a muso himself, who has been in the sales / repair >/ hire business for this sort of kit, for many many years. Interestingly >though, Rubys *are* made in China ... They are available in the U.S. see
Yah GTs are pre-tested/matched whatever. But they are not in the tube making business (unless they have done so without my knowledge).
I'm not going to condemn EH but when I've had to change them out of the first stage and pop them in say the reverb or even use them as a phase inverter/splitter, something is up with the EH tubes I have in the tube bin. I really hate reruns like any tech who takes pride in his work does but hate it even more when I'm let down by the parts I've chosen. I now offer a disclaimer and the option to install pricey NOS from Philips and Mullard. I have Philips JAN NOS in the power section of my Twin and a mixture of EH and Mullard in the tone holes. I noticed that the 'normal' input whistled like a tea kettle when turned up past 4. Removed the EH tube for that input and grabbed an old Fender tube out of the bin and replaced it and the problem was gone.
I don't know maybe it's just bad karma, bad luck, prone to coincidence etc...or maybe I just bought a bad run of EHs?? Any way the old saying 'burned boy is afraid of fire' applies.
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