CRAP VALVES on ebay ? 12ax7 MESA BOOGIE

[funkgod]

Hello all, bit of a warning and info wanted here.
I have a SWR redhead which uses a 12ax7 (ecc83) in the pre amp.
The redhead has had the valve it came with as new for 10 years with no problems.
so thought it was time for a change.
After a bit of a scoot around i opted for the ones on Ebay, and got a pair, as here....

[url="http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-ECC83-Pre-Amplifier-Valve-tubes-NEW-/230402049361?cmd=ViewItem&pt=UK_MusicalInstr_Amplifiers_RL&hash=item35a5084551"]http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-EC...=item35a5084551[/url]

I replaced my old one, and very first gig, was a sound like loud electrical fault first on louder played notes, then all the time, this was later found to be the valve VERY microphonic, and any amount of vibration would set it off, so on inspection when out it all rattley inside like a spring is bouncing against the inner case when shaken/flicked on closer visual inspection the plates dont look very well supported, and just look altogether flimsey.
I dont even want to try the other one !!!

Are these REAL mesa Boogie ones ??
The valvs say on them, "ENGL tube power ecc83" see pic
should they not say Mesa Boogie ??.

So to the point, has anyone tried these and had problems ?[attachment=53197:IMG_1230.jpg]

Edited June 29, 2010 by funkgod

[thebassman]

[quote name='funkgod' post='880653' date='Jun 29 2010, 09:24 AM']Hello all, bit of a warning and info wanted here.
I have a SWR redhead which uses a 12ax7 (ecc83) in the pre amp.
The redhead has had the valve it came with as new for 10 years with no problems.
so thought it was time for a change.
After a bit of a scoot around i opted for the ones on Ebay, and got a pair, as here....

[url="http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-ECC83-Pre-Amplifier-Valve-tubes-NEW-/230402049361?cmd=ViewItem&pt=UK_MusicalInstr_Amplifiers_RL&hash=item35a5084551"]http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-EC...=item35a5084551[/url]

I replaced my old one, and very first gig, was a sound like loud electrical fault first on louder played notes, then all the time, this was later found to be the valve VERY microphonic, and any amount of vibration would set it off, so on inspection when out it all rattley inside like a spring is bouncing against the inner case when shaken/flicked on closer visual inspection the plates dont look very well supported, and just look altogether flimsey.
I dont even want to try the other one !!!

Are these REAL mesa Boogie ones ??
The valvs say on them, "ENGL tube power ecc83" see pic
should they not say Mesa Boogie ??.

So to the point, has anyone tried these and had problems ?[attachment=53197:IMG_1230.jpg][/quote]

I have used this supplier before, not for those particular valves though.
I bought some EHX valves and both the supplier and the valves were great, might have just got damaged in the post.

Could be worth contacting the supplier to get an exchange item.

I don't want to start a valve war, but i wouldn't buy the Mesa branded valves anyway, I have heard all Mesa do is take a standard chinese valve and put their name on it.

I normally stick to EHX and have never had a problem with them, thats using them in my old Mesa 400+ and current Bassman 135. Although i did buy a NOS cryo phillips valve for my Mesa Carbine, cost me about £40 each , but it only takes one.

cheers

thebassman

[umph]

welcome to the world of new valves! modern ones don't go through the same testing older ones do, i'd get a refund as that one was obviously faulty

[dan670844]

[quote name='funkgod' post='880653' date='Jun 29 2010, 09:24 AM']Hello all, bit of a warning and info wanted here.
I have a SWR redhead which uses a 12ax7 (ecc83) in the pre amp.
The redhead has had the valve it came with as new for 10 years with no problems.
so thought it was time for a change.
After a bit of a scoot around i opted for the ones on Ebay, and got a pair, as here....

[url="http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-ECC83-Pre-Amplifier-Valve-tubes-NEW-/230402049361?cmd=ViewItem&pt=UK_MusicalInstr_Amplifiers_RL&hash=item35a5084551"]http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-EC...=item35a5084551[/url]

I replaced my old one, and very first gig, was a sound like loud electrical fault first on louder played notes, then all the time, this was later found to be the valve VERY microphonic, and any amount of vibration would set it off, so on inspection when out it all rattley inside like a spring is bouncing against the inner case when shaken/flicked on closer visual inspection the plates dont look very well supported, and just look altogether flimsey.
I dont even want to try the other one !!!

Are these REAL mesa Boogie ones ??
The valvs say on them, "ENGL tube power ecc83" see pic
should they not say Mesa Boogie ??.

So to the point, has anyone tried these and had problems ?[attachment=53197:IMG_1230.jpg][/quote]

As the general rule I would try to avoid the Chinese ones they are not much kop. Like everything Chinese its all about quality control if you get a good one great if not....

I agree with a previous poster that the modern valves just arent a patch on the old mullards, teles, etc. They where made from purer materials and the longevity and sound reflects this.

Buying modern valves is all about getting good tested ones. I think the valves from the former eastern blocs are prob the best bet like Sovtek and JJ/Tesla etc.

I run some old valve amps and studio gear and think that Watford Valves do a very good job at screening / burning in and matching the valves up. Their Harma ECC83 retro is a pretty good valve for warm and clean sounds . The geezer that owns Derek, it is a valve nut and is a good source of advice. He help me a lot with some old studio compressors I have. A lot of the modern valves are just not stable enough for this application, try one of his retros in your mesa you will like it, will probably sound better than the original mesa valve. They are very smooth, and not at all fizzy like the std modern valve stuff. The designation on the side of the valve in your amp means that is is some kind of Mullard ECC83 (English valve producer) reproduction. There is a manufacturer out there of Far eastern extraction who is making a mullard ecc83 recreation it looks like a Mullard, but thats about it. Dereks Harma retro doesnt look like a mullard but is probably the closest you will get to the sound from a modern valve. Warm, clean very musical, very low microphonics very sweet. He does cryo versions with is supposed to open up the top end a bit, But I have not tried the standard one is good enough for me.

A guitarist who I work with when he gets a new amp in the studio, the first thing he does to swap out the valves for decent matched sets from Derek. The big amp manufacturers, these days tend to use the cheapest valves they can get there hands on.

Caveat.

I am sure you know this but careful when opening a valve amp, some of the plate voltages can be as high as 300volts or more. I learned the hard way.................... there can still be current in the transformers for a long time.

[dan670844]

I just noticed something!

A 12AX7 has higher gain and will distort sooner than a ECC83. Its all about personal preference.

So if you want more of an overdriven sound go for Dereks 12AX7. If you want a very warm clean sound, tight lows, but with a reduced top end go for his Harma Retro (ECC83) he also does a Telefunken 7025 (i think STR) recreation which has a very flat response, if you want a bit more top end, its great for mic preamps this one. Just ask him.

Edited June 29, 2010 by dan670844

[umph]

[quote name='dan670844' post='880953' date='Jun 29 2010, 01:51 PM']I just noticed something!

A 12AX7 has higher gain and will distort sooner than a ECC83. Its all about personal preference.

So if you want more of an overdriven sound go for Dereks 12AX7. If you want a very warm clean sound, tight lows, but with a reduced top end go for his Harma Retro (ECC83) he also does a Telefunken 7025 (i think STR) recreation which has a very flat response, if you want a bit more top end, its great for mic preamps this one. Just ask him.[/quote]

12ax7 is the american name for the ecc83 7025 is more similar to an ecc81 or 12at7 in gain.

if you want less gain go for an ecc82 don't think they do any valves that have higher gain than a 12ax7 so if you want more gain i'd recomend modding the amp

Edited June 29, 2010 by umph

[Mr. Foxen]

[quote name='dan670844' post='880938' date='Jun 29 2010, 01:40 PM']there can still be current in the transformers for a long time.[/quote]

The capacitors are the bit that stores a charge and zaps you.

[SS73]

[quote name='umph' post='881076' date='Jun 29 2010, 03:58 PM']don't think they do any valves that have higher gain than a 12ax7[/quote]

Trying not to confuse the thread, but ecc807, has the most gain, heaters need rewiring though, nice to hear one in a Marshall.
www.pamandandy.demon.co.uk/valves/ecc80x/ecc80x.html

Back to thread, take a look on ebay for Mazda valves, if you can find old stock ones they are not as expensive as the rest and are really good valves made in england too.

[dan670844]

[quote name='umph' post='881076' date='Jun 29 2010, 03:58 PM']12ax7 is the american name for the ecc83 7025 is more similar to an ecc81 or 12at7 in gain.

if you want less gain go for an ecc82 don't think they do any valves that have higher gain than a 12ax7 so if you want more gain i'd recomend modding the amp[/quote]


I was talking about the Harma valves specifically. In any case you are right the 12AX7 has the highest drive factor, but the design does not have as good hum canceling properties as the ecc83 (this is due to its heater coil windings). The original 12AX7 design and the ECC83's and for that matter the telefunken have different plate / heater designs but are all inter changeable in most applications.
In my opinion the ecc83 mullard type is the best for bass warm tight and fat. The Teles are best for mic pre's

[dan670844]

[quote name='Mr. Foxen' post='881078' date='Jun 29 2010, 04:03 PM']The capacitors are the bit that stores a charge and zaps you.[/quote]



He he you are right , but the preamp tranny was the only bit of exposed metal that i could touch.................................

[umph]

[quote name='dan670844' post='881144' date='Jun 29 2010, 05:05 PM']He he you are right , but the preamp tranny was the only bit of exposed metal that i could touch.................................[/quote]

preamp transformer? all bits of metal should be grounded.

[henry norton]

[quote name='SS73' post='881095' date='Jun 29 2010, 05:20 PM']Trying not to confuse the thread, but ecc807, has the most gain, heaters need rewiring though, nice to hear one in a Marshall.
www.pamandandy.demon.co.uk/valves/ecc80x/ecc80x.html[/quote]
When you say "heaters need rewiring" do you mean a couple of resistors will need changing on the board or you'll need a new power transformer?

[umph]

[quote name='henry norton' post='881362' date='Jun 29 2010, 09:07 PM']When you say "heaters need rewiring" do you mean a couple of resistors will need changing on the board or you'll need a new power transformer?[/quote]
completely different pinout according to datasheet

[The Burpster]

Mesa valves are Russian sourced and some are selected.

[url="http://mesa.stores.yahoo.net/spax7.html"]http://mesa.stores.yahoo.net/spax7.html[/url]

These are genuinely worth the extra.

But you are indeed correct that Mesa tubes have the brand name printed on them.

The ENGL tubes you have in that pic are not Mesa ones and I would complain to the supplier if I were you.

I have used std Mesa 12ax7s EH and the selected SPAX7 that is the above listing and these provide by far the nicest tone of those I've used. I only get mine from reputable dealers in case I have issues as you have.

PYMTYC.

[dan670844]

[quote name='umph' post='881171' date='Jun 29 2010, 05:47 PM']preamp transformer? all bits of metal should be grounded.[/quote]

You can still get a jolt of tranny windings grounded or not. I am talking about residual current. Some amps the current can stick around for quite a while until the capacitors discharge.

[geoffbyrne]

If I can suggest reading up here:

[url="http://www.guitaramplifierblueprinting.com/"]http://www.guitaramplifierblueprinting.com/[/url]

This resource was put together by Myles Rose who can be contacted directly here:

[url="http://forums.musicplayer.com/ubbthreads.php/topics/1351234/1"]http://forums.musicplayer.com/ubbthreads.p...opics/1351234/1[/url]

He works with a lot of top musicians & has a particular interest in Dr Z Amps.

I re-valved my Laney VC30 to his advice.

I have a CV4004 (Military Spec Mullard ECC83) in my V1, a NOS Mullard ECC83 in V2 and a matched spec ECC81 in V3, along with 4 matched Groove Tubes EL84S in the power sockets.

[url="http://www.tubedepot.com/12ax7.html"]http://www.tubedepot.com/12ax7.html[/url]

The clean channel cranked is amazing when it starts to break up, but it's LOUD at that point (2x10+1x12)

If you want a cleaner sound - more headroom than either an ECC83 or a 12AX7 will give you, try a 5751:

[url="http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html"]http://www.audioasylum.com/scripts/d.pl?au...joes-tubes.html[/url]

This is what Stevie Ray Vaughan liked in his V1.

It has about 70% of the gain of a 12AX7/ECC83 (the 12AY7 and 12AU7 are a LOT less) and can give loads of headroom with the scrifice of a little total volume.

[url="http://www.vacuumtubes.com/12ax7.html"]http://www.vacuumtubes.com/12ax7.html[/url]

Obviously despite the above being guitar amps, the generalities apply completely to bass amps.

Hope this helps.

Geoff

Edited July 1, 2010 by geoffbyrne

[vocrockguitars]

[quote name='funkgod' post='880653' date='Jun 29 2010, 08:24 AM']Hello all, bit of a warning and info wanted here.
I have a SWR redhead which uses a 12ax7 (ecc83) in the pre amp.
The redhead has had the valve it came with as new for 10 years with no problems.
so thought it was time for a change.
After a bit of a scoot around i opted for the ones on Ebay, and got a pair, as here....

[url="http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-ECC83-Pre-Amplifier-Valve-tubes-NEW-/230402049361?cmd=ViewItem&pt=UK_MusicalInstr_Amplifiers_RL&hash=item35a5084551"]http://cgi.ebay.co.uk/Mesa-Boogie-12AX7-EC...=item35a5084551[/url]

I replaced my old one, and very first gig, was a sound like loud electrical fault first on louder played notes, then all the time, this was later found to be the valve VERY microphonic, and any amount of vibration would set it off, so on inspection when out it all rattley inside like a spring is bouncing against the inner case when shaken/flicked on closer visual inspection the plates dont look very well supported, and just look altogether flimsey.
I dont even want to try the other one !!!

Are these REAL mesa Boogie ones ??
The valvs say on them, "ENGL tube power ecc83" see pic
should they not say Mesa Boogie ??.

So to the point, has anyone tried these and had problems ?[attachment=53197:IMG_1230.jpg][/quote]
Hi, This is Nic, Proprietor of Voc Rock Guitars. The valve Shown in this Picture was not supplied by us. All our valves are purchased direct from the manufacturer. They are new and tested considerably before leaving our shop, our feedback clearly shows our comittment to Customer service and Item quality. The Mesa Tubes we sell have the Mesa Boogie Logo clearly stamped on the valve. The valve shown in this picture has ENGL marked on it and looks like a second hand used valve from an ENGL amplifier. Here is a link to the Mesa Valves that we sell [url="http://www.voc-rock-guitars.com/Valves-Tubes/mesa-12AX7a-valve.html"]http://www.voc-rock-guitars.com/Valves-Tub...AX7a-valve.html[/url]
Hope that clarifies. Kindest Regards, Nic.

[Mr. Foxen]

[quote name='vocrockguitars' post='1091772' date='Jan 16 2011, 08:20 PM']Hi, This is Nic, Proprietor of Voc Rock Guitars. The valve Shown in this Picture was not supplied by us. All our valves are purchased direct from the manufacturer. They are new and tested considerably before leaving our shop, our feedback clearly shows our comittment to Customer service and Item quality. The Mesa Tubes we sell have the Mesa Boogie Logo clearly stamped on the valve. The valve shown in this picture has ENGL marked on it and looks like a second hand used valve from an ENGL amplifier. Here is a link to the Mesa Valves that we sell [url="http://www.voc-rock-guitars.com/Valves-Tubes/mesa-12AX7a-valve.html"]http://www.voc-rock-guitars.com/Valves-Tub...AX7a-valve.html[/url]
Hope that clarifies. Kindest Regards, Nic.[/quote]

I notice you have KT77s, at what plate voltage do you match your valves?

[vocrockguitars]

[quote name='Mr. Foxen' post='1091847' date='Jan 16 2011, 09:20 PM']I notice you have KT77s, at what plate voltage do you match your valves?[/quote]
Hello Mr Foxen,
We test our valves firstly on several vintage Rigs for opens, leaks and general emmissions (We have Several renovated AVO Mark 4's for that task since we find them more reliable and telling on those initial tests). We then burn in and move on to the Digital curve tracer which tests the KT77 at around 400VDC plate. Our power valves are matched to within 2% of plate current and Gm (Transconductance).
We are currently out of stock on KT77's but should be getting new stock From JJ early in the new year. Thanks for you Question and keep rocking. Nic.

Edited January 21, 2011 by vocrockguitars