Updated 12/18/03
Reviews of  EL-84     EL-34
July 2003 we will be reviewing the new EL84 from Electro Harmonix.  The test results will be
written up in the Tube Primer.
Scroll down for techical reviews of various tubes as they are posted
Some of the following reviews are coutesy of Watford Valves in the U.K.  My personal
reviews are posted on a quarterly basis on the music forums on Harmony Central.com
and Music Player.com.  My reviews are more technical in nature and a bit more "black
and white", so these reviews by Watford Valves are really nice when you want some
"tone" viewpoints.  I have to say, I cannot disagree with these folks.  There is a link at
the end of the reviews to their website.
The EL-84 output tube.  Used in a lot of Class A amps such as the Vox AC series, Doctor Z,
Fender Blues Junior, Peavey Classic Series, Bad Cat, Matchless and many more.  
EL84/6BQ5 Test Report

Note- these reviews are from Watford Valves in the U.K.  They are a few years old in many cases,
and there have been many changes in regard to Chinese tubes as an example.  This is true for all
these WV reviews, which still contain a lot of great information

OBJECT OF THE TEST
To evaluate current production EL84 against New old Stock items interms of sound quality and reliability.
Thus enabling the working Musician to find the most suitable valves after testing in normal and the hardest
situations.

EQUIPMENT USED
The tests were carried out in normal playing conditions using Vox amps.  The test carried out by Greg Fryer
, myself and Brian May were to put the valves in the hardest of professional working situations. All valves
used in the test where pre Selected to have the same plate current and transconductance. G.E and Mullard
EL84 where used as a reference.

Test 1
The amplifiers used were: An original Vox A.C 10 Twin fitted Elac speakers And an original Vox A.C4.
Guitars used where a 1973 Fender Stratocaster and 1980 Yamaha SA 2000S semi acoustic.

Test 2
The second test were carried out by Greg Fryer and Brian May at Brian's home in the summer of 1998 and
in rehearsals in preparation for his 1998 world tour.

The Vox A.C30 where fitted with green backs, Vintage 30 and blue speakers and Brians Treble boost was
employed. This work led to the development of our Full drive test rig

I would like to take this opportunity to thank Greg and Brian for all their input.

EL84/ MULLARD
The Mullard excelled in my initial test and in the tests with Greg and Brian. They provided crisp ringing
sustain and huge tight bottom end with clarity which sounded larger than life. This gave the impression of
space and immense detail. It never seemed to lose control even when the treble boost was added. Indeed it
seemed to get more punchy and dynamic. Bass, middle and treble where all in proportion. We all agreed this
was a great valve.

EL84 S.T.R HARMA
This valve has always in my opinion got as close to the Mullard as you could go without buying a Mullard.
Rich creamy mid with G.E style sound stage. The bottom end is tighter and deeper than the Sovteks. The
valve under normal saturated conditions is always in control . The treble both sweet and clear. Greg and
Brian liked these valves for the aggressive edge and musical tone under treble boosted conditions . The
Harma S.T.R comes full drive tested and matched on A.C.gain.

EL84/SOVTEK
This is a current production valve which is used by many leading O.E.M including Laney & Peavey.
Generally we find that this valve has around half the anode current of a Mullard and the gain is also a lot
lower. Sound wise it is better and more reliable than the Chinese valves. In the regularly gigged amp we
recommend you buy two or three sets as they will wear out. It does not have a great deal of bass . When
pushed hard tends to go muddy. A great valve for repairers and hobbyists.

EL84M/SOVTEK
The EL84M is a Russian military surplus which is of more robust construction than the standard item. With
typical current draw of what we would expect for a military valve. In the amps this valve sounded fine with
good balance . Midrange was more detailed than its cheaper relation. With normal drive units the valve
sounded aggressive with deep bass. With Brians treble boost the midrange sound became very heavily
compressed. This to my ear sounded awful with the green backs, got better with the vintage 30 and sounded
aggressive and in your face with the blue speakers.

This sound did not have the refinement of the Mullard or Philips. It did push the solo right out which recessed
the bass and top under heavy distortion. It did have a unique mid range honk that Greg and Brian loved. We
can recommend this valve.

EL84/6BQ5 G.E U.S.A
The G.E valves have always been a favourite of mine and in the Vox amps showed all the virtues, gain,
balance and huge sound. With the treble boost in place the middle thickened up the valve sounded heavy
and crisp and did not lose definition. With Greg playing the famous queen runs the valve was extremely
touch sensitive. This is a great valve and sounded superb in the Vox A.C.30.

EL84/6BQ5 PHILIPS E.C.G U.S.A
In my own tests this was my favourite EL84. The valve has plenty of bottom end. Sweet clean midrange and
the top end brighter than the Mullard. When pushed with a real tube driver , ibanez tube screamer or
standard distortion unit the valve had quality and refinement. Cutting solos just on the edge of mayhem.
Which reminds me of the awsome guitar sound of the pistols steve Jones at Finsbury park.
The treble response sweet and clear with plenty of definition.

When Greg introduced the treble boost the valve then did appear to go over the edge. The change
happened in the mid range response which seemed to go wild. Please remember that the treble boost adds
huge gain at line level and is selected for certain frequencies. This will not cause any musician a problem in
any set up. Here we are dealing with a classic trademark sound therefore the Mullard, which excelled in this
area got the vote.  We can thoroughly recommend this valve in all applications.

EL84/JJ TESLA
This valve was not part of the test with Greg and Brian. The sound quality is great. A cross between the
bright sweet sound of the Philips with the balls of the Mullard. This is not as high gain as the S.T.R and will
therefore gives a little more headroom . Nice rich overdrive sound with clear top end response. The
balanced presentation make this an ideal choice.


EL84 Test Conclusion

The Mullard was the valve that all three of us agreed was the best overall valve. The G.E also scored very
well due to its' big sound stage. These two valves where both considered a true reference.
Greg and Brian both liked the Harma S.T.R which in the test we called N.O.S European as we are not 100 %
sure of its' origin. This was the closest in terms of tone to the Mullard and also the closest in terms of
specification. This is a high gain valve like the Mullard.

The Philips EL84 was the best sounding in the Vox as its' rich bright sound gave the amp a cleaner edge.
When the treble boost applied the valve went into mega distortion. I loved this but the valve did not have the
control of the Mullard.

The current production items we tried the JJ/Tesla sounded brighter and cleaner in normal operation than
the Sovteks. Both of these valves showed good bass and treble response under normal distorted situations.
In treble boost mode the Sovtek EL84M seemed to handle the punishment a little better.

They did sound muddy in comparison to the Mullards but they never lost control and balance seemed better
than the JJ. The JJ seemed to go very middley.

Overall many good sounding reliable EL84 on the market which can suit all your playing situations.

These tubes are all available over the net from www.watfordvalves.com
The EL-34 - Tube Reviews

The classic Marshall / Hiwatt sound, and used today in many American amps.  These
tube reviews were done by the folks at
watford valves
EL34 Test Report

OBJECT OF THE TEST
The aim of the test was to evaluate current production EL34 against New Old stock items. This to enable the
working Musician to select the most suitable and reliable Valve for the relevant style of Music.

The emphasis was placed on current production items which should be easily attainable. The quality of
current production EL34 has greatly improved since the start of the decade. The reference valve used was
the Mullard EL34 and the same applies now as did at the start of the decade. If you want the ultimate tone,
simply buy the Mullard.

EQUIPMENT USED
The amplifiers used were: Marshall 100 super lead & 100 super bass into 4 x 12 cab loaded with Celestion
Vintage 30's.

Guitars used where a 1973 Fender Stratocaster, 1980 Yamaha SA 2000S semi acoustic and a 1980 Gibson
Les Paul Standard.

The tests where carried out to provide in real working and playing situations how the valves performed.
Valves were selected for low microphony, low noise and similar gain characteristics with the Mullard EL34
used as the reference. The pleasing thing is that the standard of the current EL34 if far superior to those that
where available at the beginning of the decade. But if you want ultimate tone, the advice is still the same -just
buy the Mullards.

EL34/ MULLARD SINGLE GETTER
The Mullard provided crisp ringing sustain and huge tight bottom end with clarity which was unrivalled in this
test. The Mullard has it all. The valves sounded huge with wide imaging and detail. When the valve was
pushed hard it sounded ferocious with cutting bite, it meant business. Power chords rocked the very
foundations and when the valve was saturated it never lost control. In history not many valves can claim the
mantle of best audio valve and best guitar valve. The Mullard still reigns supreme.

EL34WXT/SOVTEK
The WXT is an upgraded Russian valve which replaces the EL34G & EL34G plus. The manufactures claim a
unique grid block design which improves electron flow and gives the valve higher output, which they claim is
6% higher than the competition.

The valve has a rating of 25 watts plate dissipation and is a vast improvement on its predecessors.  It has a
higher anode current draw and higher gain and is very stable. In reliability terms, again the valve has stood
the test on the road in countless Marshall amps.

In our high plate volt test of 12 hours at 500 vdc plate & screen all 24 pcs tested come through with no
problems.

The valve has good bottom end response which is nice a tight.  The valve does not have a big sound stage
like the Mullard but instead a one dimensional focus which is great for lead work as it pushes the sound right
out. When saturated, the distortion had a fuzzy element to it which is great for grunge.

Top end response can go a little grainy and get hard on the ear but generally nice top end chime.  I can
recommend this valve for use in all applications.

EL34/SVETLANA
The Svetlana is the valve which is used by many o.e.m manufactures with its' biggest U.K user being Marshall.
Svetlana claim its' special plate material gives it the best performance under overload conditions.
Reliability is not a problem as this has stood the test of time. In our endurance test all valves came through
with flying colours. The thing that really impressed me was that the readings did not change. They have
defiantly got the ageing process sorted out.

The valve has a more liner performance than the Sovtek and the bass response was better defined . The
sound stage was also bigger than the Sovtek gave it more of the trad British rock sound in the Marshall.
The valve was very well balanced with the midrange in correct focus. The top end was smooth and crisp.
Great valve which again can be thoroughly recommended.

EL34/E34L S.T.R HARMA
The Harma is a specially tested/selected valve which is of European manufacture.

The valve has the widest frequency response and the highest plate dissipation ( 30 watts) of the valves
tested.  The valve has a number of features such as gold wound grids and heavy grade glass which makes
this a rugged valve for road use.

The bass response is big and bold with the valve being very well balanced. The tone was bright and slightly
forward sounding. The sound stage was big Mullard style. Reliability wise these are rock solid and have been
road tested by Ben Matthew's of British rock band Thunder on our behalf over the past two years. The mid
response is clear and sweet. When driven hard the valve never loses control with rich distortion blasting
through. I really love the top end response which makes a Marshall sing and is easy on the ear. This is the
best current production made EL34 bar none.

EL34/E.I YUGO
These yugo valves failed the endurance test at an alarming rate. Red spots, instability and one valve was
showing signs of arcing. Of the ones that did come through ( 7 PCs out of 12) the valves where drawing of up
to 10 m/a less than when we started. Therefore these would need a burn in process before matching.
The valve lacked the bottom end response of the Mullard, Sovtek, Svetlana and Harma. It was light and
woolly by comparison. The valve had a nice top end response which was not harsh and easy on the ear. The
midrange response was very recessed and very fuzzy when pushed.

Overall this valve is not as good as the Sovtek or Svetlana if you want the classic rock sound. Indeed we
were not impressed at all as the valve just was not in the same league as the others. Reliability and electrical
construction was of a poor standard. Avoid these.

EL34/6CA7 E.I YUGO
This valve showed the same trait as its' slimmer brother. These ones were supposed to specially tested. This
may have been done at 250 vdc plate and screen which is totally pointless when considering use in guitar
amps. It simply does not like moderate plate voltage. So much for the testing. In the UK many hi-fi companies
fit these. All we can say is that customers actually ring us and thank us when they replace the valves with the
Harma, Sovtek or Svetlana. Some customer has also found these unreliable and unstable when they have
used them in kit amps.

The sound stage is nice and big with the valve sounding clean and detailed at low volume. When pushed
hard it simple seemed to go muddy and loose control. This resulted in a horrible nazel compression. Indeed
the distortion seemed more like a 6L6 than an EL34.

I think for low voltage hi-fi valve this might be o.k as its worst results where when it was pushed into clipping. I
would not use this valve for guitar amps therefore we cannot recommend it.

EL34/CHINESE
The Chinese valves have a bad name for reliability, being electrically inconsistent and of poor build quality.
Some dealers are saying that they have improved and so we thought we try them. The result, they are as
poor as they ever where. These are the only valves to have ever blown more than one fuse on my test rig.
When you find some that work they have absolutely no top end, sound dull and unrefined.

All I can say is that the box and the printing is possibly worth more than the valve it self. Don't bother with
these.


EL34 Test Conclusion
The general standard of EL34 has certainly increased since our first tests which where carried out at the
start of the decade.

The battle ground comes down to three valves all of which have their own virtues. The Three valves are the
Sovtek, Svetlana & the JJ/Tesla with other valve manufactures not being able to currently compete.

The best sounding valve is the JJ/TESLA which we sell the selected Harma S.T.R version. This I found the
closest to the Mullard in sound quality and soundstage.

The Svetlana valve also has great Mullard bottom end but is not as involving or as forceful as the Tesla.

The Sovteks are great blues valves which overdrive nicely and push out nice fierce solos. They can sound
grainy at the top end but I don't mind that , after all it is rock and roll.

The Mullard is still king of the pile followed by the Siemens in the top rankings. The gap is definitely getting
closer, however I do not feel this valve will ever be bettered. The prices will continue to rise so if you require
the ultimate then it will pay you to buy now. If you do not wish to break the bank then the Harma/JJ Tesla,
Sovteks and Svetlana are all good choices which you can try until you find your favourite.
Technical report on the Electro Harmonix EL-34EH
Comparing the Electro Harmonix EL-34 and the JJ EL-34
tubes.  Test completed 3/16/02.  You can see the results by
clicking here
A retest of the Electro Harmonix tube completed 3/18/02.  This was
with another batch where we asked for a different rating.  This last
batch was VERY close to our mid 1960's Mullard reference test
tube, possibly as close as a group of Mullards from different
batches.  This may be a better test than the JJ/EH test earlier, as the
JJ is a higher powered tube, higher than the Mullard also.  This tube
now looks to be a nice consideration for EL-34 based amps when
you want to come close to the original sound if the original amp had
Mullard or Siemens tubes, such as a 60's or 70's Marshall or Hiwatt.  
You can see the curve traces by
clicking here
Electro Harmonix EL-34EH Test

3/4/02 - 3/10/02 @ Guitar Amplifier Blueprinting  -   West Hills CA

Note:  Since this original report was done, there were two additional Electro Harmonix tests done.  
One was to compare this tube to the JJ tube, and the latest was to compare to the Mullard reference
tube.

Worksheet and curves picture by clicking here

This tube proved to be a good offering in todays new tube market.  The EH version of the EL-34 is built in Russia
at the Reflector Factory where tubes sold under the Sovtek brand name are also made.  This tube is made on
different tooling than the Sovtek tubes.

This tube claims in its advertisement to be a copy of the older Mullard tube.  It appears that the Mullard was the
model for this tube, and in many ways it testing showed it to be similar in many ways.  There are however, some
differences, so if you are looking for the sound of the original Mullard, than it seems NOS is the only viable option.

The EL-34 tube did not have the same popularity initially in the USA as some of the 6L6 based products.  Marshall
was the primary amplifier in use in the USA from overseas, and there were not all that many models available.  
There really is no particular "Marshall" sound in one way ? that is, the models 1987 and 1959 were the models of
the mid 60?s in this country, and this was also a time of much change for Marshall.  The JTM-45 went through
KT-66, 5881, and 6L6 variation, and then the 50 and 100 watt models used Mullard, Siemens, Telefunken, other
OEM tubes, and later for export used the 6550 tubes in the 50/100 watt models.

Fender on the other had, had long runs of a number of models which used Sylvania 6L6 tubes.  The amp/tube
relationship for a specific sound is more closely tied with Fender than with Marshall I think one might be able to
say.

This is not good or bad, and for EL-34 amp users, it can be thought that one can use a lot of different tubes and
still have the "Marshall" sound.  Todays amps that use this tube such as the Riveras and Bogners ? Mesa and
VHT ? Matchless, Carr, and others, are different amps with different designs than the old 1987 and 1959
Marshalls.  So experiment with your output tubes and keep an open mind and ear.

Our EH samples came from five sources.  We had 18 tubes that we asked for in the middle range, and asked for
"the same rating as what would be a Groove Tubes #5 rating".  We established that the "retail" price of these
tubes were $45-48 a pair and $90-98 per quartet, with matching included.
 We found our suppliers differed in
their idea of a GT #5 rating.  In the last series of the test, we asked for a current draw of 95mA using
265 B+ volts and a bias of -13.5 volts in triode mode, and 265V plate, 250V grid, for the pentode tests.  
This yielded closer matching from our suppliers as well as showing us which supplier uses more
sophisticated equipment for their matching.

In our matching tests, its was once again confirmed that most folks use the conventional current matching method,
as the tubes were close or almost perfect in this aspect, but fell a little short when looking at factors such as
transconductance, rise time, and linearity.   Matching for current draw at a static voltage and bias is a bit different
than what the tubes will be subjected to in a guitar or bass application.

While matching in this fashion yields fine results in a guitar amplifier, it is one of the factors that makes some amps
sound terrific of a specific model of amp, but one amp just stand out and sing in the same group.  This is what
sparked the idea of "guitar amplifier blueprinting".  One cannot expect tube vendors to match tubes, one at a time,
for 30 minutes per tube at times, on scopes.  The cost of the tubes would be out of the reach of most of us.  In a
Hi-Fi application where tubes last years, this might be fine, but in the torture of a guitar amp where tubes are
changed more often, this is not as practical.

While on this subject, this is one of the reasons that if you have something like a bias probe or bias king, you may
find some tubes closely matched in your amp from some folks, and not as close from others.  If a tube is off by
more than 10%, the tube may have had some shipping damage.  Just a simple drop in the UPS or Fedex truck can
move one of the little grid wraps just a few ten thousandths of an inch, and there goes the matching.  Tubes are
fragile.

It is also important to keep in mind that some folks measure a number of parameters such as current draw,
transconductance, grid leakage, gassification, and other factors.  If you look at these tubes at a static voltage on
the plates with a static bias voltage, they might appear to be a few milliamps out of matching, but when you put
them on more sophisticated test equipment in dynamic conditions, they tubes match up more closely than those
tested using static methods. If you want more information on this subject, the old RCA and GE tube manuals have
entire sections on "testing".  This is the reason that tubes from Groove Tubes appear at times to have a different
"match" than a tube tested on static load equipment.

Bottom line on the matching issue, is that most folks supply you with a tube that is much more closely matched in
some ways than the specifications called for as being matched in the past.  Again, I said "in some ways", and if
you want your amp to "sing", this is one of the factors.  Just like a race car, you want to find all the weak links in a
chain.

With all this above in mind, the Electro Harmonix EL-34 was a fair tube.  In one test phase, we were looking for a
max output of 140 mA as this was our target, which was the maximum spec for the EL-34 at the settings for this
portion of the test.  The tube did not produce this rating, topping out at about 120.8 mA.  This is NOT to say that
this is a low power tube.  At this power output, it is well over the 25 watt maximum overall spec of the tube, actually
about 36.24 watts.  In  Marshall JCM 800 50 watt head, the measured output at 400Hz and 1000Hz was in excess
of 62 watts.  In a model 1959 Marshall 100 watt head, the output was 132 watts.  You can see some of this in the
worksheet with its link at the beginning of this report.

This tube had 12-15% less output than the Mullard, Telefunken, Siemens, or JJ tubes.  But, the power was still
well above published maximum allowances for the EL-34.  It had about 5-10% less power than the Svetlana tube,
but the had more linear curves at lower B+ voltages.   This is not a tube with much harmonic content or detail.  
Most other current EL-34 tubes seem to have a larger sound image.

At plate voltages over 380 volts, the tube became a little less linear in its operation.  At voltages below 380 volts,
its curves were closer to those of the Mullard tube test samples we used.  In comparison to the Ei tube under its
first phase of tests and the Svetlana, the Electro Harmonix tube had its characteristics closer to the Mullard.  This
tube was also just as linear in the range of 380-575 volts as the Svetlana, and more linear than the Ei tubes.  The
Ei and Svetlana offerings in early 2002, are not the best example of Svetlana past production.

To conclude, the Electro Harmonix EL-34 is a consistent tube with fair curves and a decent value in todays
market.  If you want a little more of the 60s and 70s British sound in your "todays design" amps, with a little less
edge, this may be worth consideration.
Ruby Tubes EL34BSTR Review

These tests were completed on September 25th 2002 at Guitar Amplifier
Blueprinting in West Hills California.

The Ruby Tubes EL-34B STR is a Chinese tube of a proprietary design made for
Magic Parts, who is the distributor of Ruby Tubes.  What a lot of people do not
realize, is that many USA companies such as Magic Parts and Groove Tubes
invest large amounts of money in tooling and design, working directly with the
world?s tube factories on designs specific for their own client base.  Hopefully, the
world?s tube factories will keep the tubes and designs which proprietary designs
and tooling produced, in confidence to the folks that provided the capital for their
development.  If the factories do not do this, we can all forget about new designs
and improvements in the future.  This is one reason that the major tube vendors
get along, share ideas, and work together for the overall benefit of the tube
industry in general.

Over the last months at my ?other job? at Groove Tubes, I was given a single
sample of this tube to test.  The initial results were inconclusive, as I had only a
single tube as a sample.  I was asked to procure ten more tubes for a more
detailed test.

Upon testing of the ten tubes, the results were less than spectacular.  I contacted
Tom MCNeil, the owner of Magic Parts / Ruby Tubes, to give him my findings.  
Tom was very open to my criticism, and we talked at length as to my findings.  I
told Tom that ten tubes were not a valid test, as the sample was not large enough,
and he agreed.  Tom also pointed out that the bulk tubes which I received, were
not the tubes that were sold to stores, or the end user, and had not been tested
or matched in any way.  (As a side note, even without matching, these tubes had
a high level of consistency.

I was able to procure additional tubes, just like any ?man on the street?, to see if
the Ruby Tubes matching made any difference.  Many folks today have what they
call ?matched? tubes, which fall short of what I personally term as matched.

What follows, is the result of testing, measuring, and screening, with a bit of
listening and playing.

One ? The matching tests.  The match of the tubes I tested was excellent.  I have
no complaint.  Ruby does an excellent job.  The tubes are marked with PC, TC,
and Nr.  I think PC is output, TC is transconductance, and Nr., well, I don?t know
what this piece of data was, but the bottom line here is that they do a great
matching job.

Two ? High Voltage tests.   Everybody knows that Chinese tubes don?t hold up to
high plate voltages ... right?  Well, not as common any more.  In the last six
months, the Chinese tubes have come up in all aspects of quality, as these were
no exception.  These tubes had no problems at 575 plate volts operating, and
675 volts for static tests.

Three ? Output.  Again, an issue of the past was low output in Chinese tubes
when compared to the Russian offerings.  In the past, Chinese tubes were about
20% down on power.  Today, they are averaging for their 6L6?s and 6550?s,
about 15% power increase over the Russian offerings.

Four ? The curves.  These tubes are linear.  If you feel that something like a
Svetlana or Electro Harmonix EL-34 is a bit tame, and a JJ or GT E34L is a bit too
much, these may be worth a try.  They were smoother than the E34L and not as
aggressive, yet had a more pronounced mid and low end than the 25 watt EL-34
Svets or EH?s.

Five ? Their construction.  The bottles are oversize compared to a ?normal?
EL-34 which has a straight bottle.  The bottle is a bit larger in diameter than the
base.  The glass is strong, and the mica spacers are well shaped and had nice
contact.  These are not microphonic tubes.  The base was of nice material, and
the pins are nicely done and smooth, which tends to make old vintage sockets a
lot more happy than dip plated pins that are from stamped materials.  The internal
construction and welds are first rate.  The plate assembly has two slots in each
side, which allows, with a few tricks, the inspection of the operation of the tube.  
The coatings have much more ?blue? than ?red?, meaning a lower percentage of
impurities being heated to red hot temperatures than some of the current Russian
offerings.

Six ? Taking a listen.  For this test we used the typical Strat, Les Paul.
Rickenbacker 360-12, Tele, and PRS McCarty soapbar guitars.  Amps were
Marshall 1987 50 watter, Matchless C-85, Marshall 100 watt 1x12 combo, Marshall
JCM 2000 series, and an Ashdown 50 watt head.

These tubes had more overall output than the EL-34EH, but less than the JJ
E34L.  The sound dispersion with test tones at 1 meter at 200, 400, 600, 1000,
1200, 2000, 3000, and 4000 Hz, we wider than the EL-34 Electro Harmonix, on
par with the Svetlana EL-34, and actually only 4 degrees narrower than the
Mullard and Siemens NOS test reference tubes.  In the 1200 Hz and 4000 Hz test,
this tube actually had a bit larger sound stage image than one of the NOS
reference tubes, and we are not telling which, as it is not important as this is not a
test of NOS tubes.

These tubes are linear.  Playing softly and increasing the level via attack or guitar
volume produced smooth and expected results.  This is a point often missed in
many tubes, especially EL-34?s, which can come on like gangbusters out of
nowhere.  This is what I call the ?afterburner syndrome?.

Everybody liked these tubes, and one resting-place for them will be in the 1x12
100 watt Marshall Combo mentioned above.  For those of you in the Los Angeles
area, a set of these will be in Mike?s amp, and Mike is over at Norm?s Rare
Guitars.  If you want to have a listen, give me about a week and give Mike a call
over there.  Like I said, these tubes are not prone to microphonics.

Complaints.  Everybody that knows me can attest that I can always find fault with
anything.   My complaint here, is they are low in cost, and a great value, and
versatile ? and will be another competitor out there in the market.

Perhaps I can talk to my ?other boss? and work a way to have these as part of
our inventory and offerings.  There are a lot of great EL-34 tubes out today.  In
the end, it boils down to personal taste and preference.  Some amps ?prefer?
certain tubes over others.  It is great to see a nice and versatile offering on the
market at a very attractive price.

I wish the best of luck to Tom and Magic Parts / Ruby Tubes, from Guitar Amplifier
Blueprinting officially, and ?unofficially?, from my ?other employer?.  I am sure my
other employer would also enjoy the fact that tubes are getting better.  Even with
the current economy, today with MTV, VH1, CMT, etc., we have more dreams than
ever of all being Rock Stars.  There are more amp and guitar makers than ever
before in the history of the electric guitar, bass, and amp.  It seems like the tube
factories are seeing this!

Myles S. Rose
Guitar Amplifier Blueprinting
General EL-34 data