Fender Hot Rod Deluxe Tune-Up

--Augustine Ortiz, Jr.--
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STILL IN PROGRESS

Introduction

So my trusty Fender Hot Rod Deluxe is due for some work. I have had it now for almost 6 years. It is still pretty much stock and for what I use it for it sounds ok. But I figure might as well experiment.

There is much controversy over this amp. Some love it some hate it. Back in 1999 I was heading off to college and sold my Crate cheapy full stack. It sucked and I used a Metal Zone into the clean channel. The distortion on it sucked. I was looking for a good combo that would be loud enough for a band.

At this time I was a pedal user. To me Amp distortion always sucked. Of course my experience was with Crate and other Fenders. My focus was playing not gear... I didn't have the money. I was doing Jazz, classical, and Metal. I figured any amp with a clean channel would work. So recommended to me by a country/rock player was the HRDlx. After looking into them some I learned that they had the cabinet of a Bassman with the bite of a guitar amp. I really liked the Bassman's clean tone. So I decided to go shopping.

I went to a music store and plugged my MT-2 into the HRD and loved it! Please remember my tonal experience here.... Plus for the price I was happy.

Later I got a Zoom GFX-8 and Sovtek MIG 100. Now I have an ENGL Powerball and money, so my gear has updated and my love for the MT-2 into my HRDlx has faded. So I have been looking at new amps. But I have decided to wait.

Realistically, my Fender is a pretty nice amp. All tube, pretty sweet but mellow clean tone. It rocks for that country twang. It cuts through the mix and takes OD pedals incredibly well. The Distortion on it could use some work, but I definitely think it is usable and has a voice of its own. I rarely use it though. I just run a OD pedal or something in front.

Bottom line, it is a solid amp that has served me well. Currently I still gig with it and it is my "everything else" amp. My ENGL does Metal, the Fender with OD Pedals and my GFX-8 FX processor does everything else. But I figure it would be fun to play and experiment.

My Goals

So my goals are different than most owners of this amp. Most people want it to sound more vintage like an original Fender from the 60's and 70's. So they look and study the original components of those and try to mod this match. I am looking to make it work better for what I do.

Of course tone is subjective.

More Clean Headroom - This is only a marginal problem for me. But at high volumes it would be nice for better cleans.
Versatile Clean (Pedals) - This amp pretty much already covers this. But the ability to continue to take pedals well. From Jazz to Blues to Rock to Downright Death Metal. Since this amp I often take to rehearsals where I don't want to bring a stack, this is probably the most important.
Better Distortion - After discovering good amp distortion, this would be a bonus. However, not critical in this application.
Hold Up with a Band - This is pretty much already covered but a big priority. It must be able to cut through and go un-miced with un-miced drums for smaller venues.
Be Reliable - This is also very important. I use this with no backup all the time. Since a big thing for a combo is to be portable, carrying two destroys that.
Just Sound Better - In my case I am not really dissatisfied with the sound. But to experiment, it never hurts to try and make things better.

The Research

Fortunately this amp is very popular. For as much as many people hate it, there are really a ton sold. So finding information about mods and such is pretty abundant. I don't really want to modify the electronics. So I will stick with tube and speaker experimentation.

So here are some of the results that I have found on the internet and talking to people. Of course I will pick only a few. I have limited funds and returns after use are generally frowned upon. Plus the places that offer good return services are genearlly considerably more expensive. So I will try and pick items that I can possibly use for other amps I own or sell relatively easily.

Speaker Research This is a big one since it basically is a permanent EQ. I have had heads that I have used with different speakers and cabinets that have made a world of difference. I know that a lot of problems can be fixed with EQ, but as a gigging guitarist, the less I have to carry around the better.
Now different speakers sound different with different cabs, amps, styles, etc. to different people.

Eminence Legend 125
(stock speaker) I know that Fender specifies that the speaker is a Eminence Special Design speaker but from many sources it is just a Legend 125. Plus this is specified as the standard replacement speaker on Eminence's website.
Many have gone back to this speaker after trying a bunch of different ones. Many also find it farty and harsh. I don't mind it too much. But it never hurts to try a replacement.
On the upside this one as 99dB SPL and cuts through the mix. I think this will end up being the basline speaker for these aspects.

Eminence Legend M12 This speaker is also on the Eminence Cross Reference as being a replacement. I have heard this one is like JBL speakers and has a lot of highs. Ear Candy Cabs states that it is well rounded and good for metal and rock with a top end sting and sizzle.
Interesting, but personally I like less sizzle and smooth highs. Also at around $60 or so street price, I think there are better options.

Celestion Vintage 30 Some people swear by this speaker for everything. A whole lot of people love this speaker in this amp as well. A few say that it has too much bass and will shake the cabinet apart.
What I do have is an Avatar 2x12 open back with a Celestion G12H30 and Vintage 30. Running this amp through really brings out the bass, but it does sound good. Personally I like Vintage 30's for a lot of things. I will probably pull the speaker out of my 2x12 to try out.
With 100dB SPL and it mix-cutting abilities, this will definitely be a candidate.

Eminence Governor This is from the relatively new line of Patriot and Redcoat series of speakers that have just been getting awesome reviews. It is supposed to be similar to a Vintage 30 without the bad stuff and more good stuff. A lot of people rave about this speaker. My only concern is that the extended low end my cause some troubles.
I am already planning on replacing a couple G12H80's that are mixed with Eminence V12's in one of my 4x12's. So this one will definitely get tried out. At 102dB SPL it should be loud. But there is also not a single bad review for this speaker.

Celestion 70/80
Celestion Seventy-80 This comes stock in many Randall amps. I know it is also standard with the Traynor YCV40 which to me seems like a better version of the HRD. These are pretty cheap ($30) and supposed sound pretty good with this amp.
I am not sure if I will try this one. The Traynor YCV40 sounded way better with a Vintage 30. I figure for $20 or so more dollars I can get a much better speaker.

Celestion G12H80 I believe that this speakers comes standard with Line 6 Modelling amps. Avatar Speakers is having a blowout sale on these. I really don't care for them much in a 4x12 (mixed with Eminence V12's), however since I already own a couple, it is worth trying out.
In general many think this speaker is kind of steril. That is probably true since it is supposed to cover pretty much all styles of music. I find them to be harshly bright and not cut through the mix very well.

Eminence Screaming Eagle This is one from the new Eminence Patriot series. It comes recommended for the HRD since it relaxes the bass some. It is also supposed to be a pretty versatile speaker, but kinda bright. I think I will pass on this one.

Reverend Alltone A lot of people love this speaker in their HRD's. However most of them are more interested in classic rock and other lighter stuff. From what I have read, this speaker does not like Metal. But it sounds like a great speaker and the price isn't too bad.
This one is a touch choice. I think I might see if I can return it if I don't like it. It is supposed to be a hot-rodded Jensen.

Jensen C12N This speaker came out with the HRD Limited Editions. It is supposed to give a more traditional Fender sound. From my past experience with these, they are pretty bright and chimey. My concern is that they may not do Metal well and be a bit too HiFi.
I think if I decide to go this route, I will get my hands on a Reverend AllTone first.

Eminence Swamp Thang Recommended as a replacement by Eminece for the HRD. I am not so sure about this. Appearantly it is voiced to be bassy, so with the HRD it might be a bit much. I think I will skip out on this one.

Eminence Red White and Blues This is supposed to be the American Cousin the Governor. Appearantly it is not recommended for Metal. Definitely considering this one if some of the others don't work out.

Eminence Tonker This one looks interesting. Many people like this speaker but not many decided to continue using it. Instead many of them switched to another in the Eminence line. Ear Candy Cabs in particular really like this speaker as being the one that can do anything in their cabs. It gets their highest review.
Some don't like it with distortion because it is too piercing. It has the highest powerhandling of any of them and seems interesting. I will consider this one in my purchases.

Eminence Private Jack Supposedly similary to a Celestion Greenback, this speaker was chosen by many in 4x12 cab configurations. This one looks interesting and supposedly is popular for Fender and Vox replacements.
Appearantly the original Greenback is pretty bad in Traynor YCV40's. I am thinking I might avoid this one.

Other Speakers Of course there are a ton of speakers out there to try. Weber, Tone Tubby, othere Celestions, Jensen, etc. These ones above are the ones that really stood out and that there had been some discussion about. I have a Jensen MOD 70 in my Behringer V-Ampire and a couple Eminence V12's that I might try for fun. But at the same time I don't want to spend all my time swapping speakers.

So I think I will go ahead and buy an Eminence Governor and an Eminence Tonker. I figure if I don't like the Governor with this amp I have a home for it in a 4x12. If I don't like the Tonker, I can sell it. I have a feeling that the Tonker may fit better.
Even though many complain about the abundance of bass, I think that it is good for a live setting to give a fuller sound.
I am considering getting a Reverend Alltone with their 14 day return policy. But I feel bad breaking in a speaker and all and then sending it back. Maybe I can just order a "used" speaker and go from there.

It amazes how much information there are on speakers. I just wish I had unlimited funds and unlimited time to check out all the speakers and such. Maybe someday when I no longer have to work...

So now on to even more decision making... tubes.

Tube Research It amazes me that there are still many tube brands. I would say that most brands like TAD, GT, Ruby, ENGL, Fender, Mesa, etc. are just testers and re-labelers of tubes. But even with that, there are still a surprising number of manufacturers like JJ/Tesla (Slovak Republic), Shuguang (China), Sovtek(New Sensor, Russia), SED (Russia, formerly Svetlana), Electro Harmonix (New Sensor Corporation, Reflektor factory, Russia), Svetlana (New Sensor Corporation, Reflektor factory, Russia), Ei (Yugoslavia), and some of the re-labelers have factories make custom tubes for them as well.
Once again all of these work for different people, in different amps, and for different styles. Fortunately tubes are a bit less expensive and are relatively easy to swap and test with.
NOS Tubes - So I am not going to try NOS tubes here. I know that so many people swear by them and that they are more reliable since built for the military and such. However, even though I agree that many of them sound great, they are expensive, often hard to find, and often not worth it to buy and experiment with. Powertubes wear out with use, no way I will ever go NOS with Powertubes. Pre-amp tubes, I think the only reason to have NOS tubes around is to compare with current production tubes. Even though pre-amp tubes last longer, NOS to me just makes me nervous. I would rather sacrifice a bit of sound for the piece of mind of easily finding replacements. Especially since my amps do see a lot of use.

Power Tubes

Sovtek 6L6GC/5881 WXT
(stock) This is what comes stock with the HRD. It is relabeled by Groove Tubes (GT) and biased cold by Fender. These have a really high reliability being originally designed for airplanes. To many they aren't great, but they aren't bad either. The ones in my amp are surely worn out. But also I have other amps that take these, I will probably buy them for testing and baseline comparison.

Electro Harmonix 6L6GC From what I can gather, this is pretty much an improved Sovtek 6L6WXT+. The Sovtek is supposed to add 20% more output. Both are modelled after the RCA Blackplate. I use these in my Sovtek MIG 100 and love them. Others have had great reviews about these in the HRD. Since I have some, these will definitely be tested.

JJ/Tesla 6L6GC Now I have never used these tubes but so many rave about them. Of course there are those that don't like them. They are supposed to be a bit less bright and be harmonically rich. A trusted guitar tech friend of mine swears by these and eurotubes recommends them as well.
I figure I will get a quad to try in my Sovtek MIG100 as well.
From picture inspections, these seem to be the same as the ones relabled by the Tube Amp Doctor (TAD).

Shuguang 6L6GC These are relabled by Ruby and are supposed to be of pretty high quality. My ENGL Powerball has these in its poweramp. I will just steal these to test with.

SED 6L6GC I have used these in Mesa amps and they are pretty nice. Definitely on the vintage side of things. Many reviewers agree. I have heard that these don't do so well in the HRD. I think they would do better if I was more interested in a classic Fender sound. But I think I will steer clear of this one. Not that it is a bad tube by any means, I just have little confidence that it will work for me.

Svetlana 6L6GC These are the new tubes made by New Sensor. They are supposed to sound pretty good. These are relatively new and I haven't heard much about them. I think I will hold off on these for now. Maybe next re-tube.

6V6 Tubes Many people have tried using rugged 6V6 tubes to lower the power and get earlier break-up. I think this would be great if your focus was more on the distorition. For my purposes however, I will stick with 6L6's.

7581 or KT-66 Tubes 7581 tubes are supposed to have a higher power handling but similar specs to 6L6GC. The problem is that they are only NOS. I couldn't find any that were in current production. KT-66 tubes are supposed to be good as well. However I have also read that you are better off getting a nice 6L6 versus KT-66.
I think I will stick with 6L6's for my purposes.

Preamp Tubes

Chinese 12AX7A
(stock) So far I have been happy with these. I might try a set of the latest generation ones since they have been getting great reviews lately. But these ones in here have been reliable and still work great.

Sovtek 12AX7A This is the standard tube for most guitar amps. Personally I have never been excited about these tubes. I have a few that I will probably try out. This is probably more just a standard to compare against.

Electro-Harmonix 12AX7EH These are supposed to be very balanced, have low noise, and very low microphonics. I have a set of these in my Sovtek MIG100 and Fender Champ. They are very clean and clear, but a bit gritty with OD. Since I have so many of these, they will definitely be tried out.
With the HRD, they supposedly work well in all positions and best as the Phase Inverter.

JJ/Tesla ECC83S There are many people that swear by these tubes. There have been reviews that they are darker and to some lifeless. However there have been many reports that these tubes really help the drive channel on the HRD.
Appearantly the high gain versions are supposed to sound better. Also they are supposed to be muddy as a PI. I personally have no experience with these tubes. But I will buy some to try.

GT 12AX7-M This is Groove Tubes Mullard copy. I have heard some great things about the tone of these tubes in anything but high gain. I have also heard bad things about reliability of the earlier runs.
I will probably buy one for V1 to try in other amps as well. My only concern is that it might be too rich sounding for pedals.

Ei ECC83

Random found Info

I've had a few of these come through the shop (Including my son's) and here's a tip to help extend life. In 2 cases the bias pot took in dust and lost contact. This drops the output tube bias voltage to "0 volts" which causes the current to go very high in the tube. Interestingly, the power transformer has enough internal impedance to cause just enough current limiting to prevent the fuse from blowing. This resulted in burnt out power transformers for these 2 amps. In both cases the player noticed the sound was getting squash but continued to play as they were gigging. At least they played til the amp quit. Anyway, I added a 100K resistor from the top of the bias pot to it's wiper. This quick fix will keep the voltage pulled up (and the current under control) should the pot lose it's ability to conduct. Adding the resistor changes the bias slightly but it can be easily compensated with the pot setting to allow proper bias. The idea is that it's a quick easy bit of insurance to an otherwise decent amp. Bob D. DST-engineering.com

References

For this there were many references on the internet and in person with store clerks and amp techs.

The Unofficial Fender Hot Rod Deluxe Owner's Guide - Tons and tons of great information on these amps. Of course more geared towards the vintage sort of vibe. But there is tons of information on repairs, mods, speakers, tubes, and technical info. This site is essential if you have an HRD.

Dougs Tubes - Excellent tube resource, great prices, and awesome customer service. I order my tubes from here whenever I can.

Eurotubes - Excellent source for JJ Tubes and information. If you are looking to re-tube your amp, he has kits available that are very handy. For the HRD he has several options for re-tubes for various tonal goals.

Harmony Central Amp Forum - Great discussion board. After doing searches and asking questions, I found a lot of useful information.

Harmony Central Amp Review Database - Great place for information. The HRD review page has excellent info, but also be sure and check out the reviews for speakers and such too.

The Gear Page - This a great forum with a lot of useful information. In particular check out the huge thread on the new Eminence speakes.

After Midnight Custom Guitars and Amplifiers - Local shop in Santa Fe, NM. Brad is an awesome guy and he has a cool selection of stuff. He does all my guitar work and has great prices.

ALL CONTENT COPYRIGHT Augustine Ortiz, Jr. 1/11/2005
You may link to these pages, but please do not copy without permission

Speaker Research This is a big one since it basically is a permanent EQ. I have had heads that I have used with different speakers and cabinets that have made a world of difference. I know that a lot of problems can be fixed with EQ, but as a gigging guitarist, the less I have to carry around the better. Now different speakers sound different with different cabs, amps, styles, etc. to different people.
Eminence Legend 125 (stock speaker)	I know that Fender specifies that the speaker is a Eminence Special Design speaker but from many sources it is just a Legend 125. Plus this is specified as the standard replacement speaker on Eminence's website. Many have gone back to this speaker after trying a bunch of different ones. Many also find it farty and harsh. I don't mind it too much. But it never hurts to try a replacement. On the upside this one as 99dB SPL and cuts through the mix. I think this will end up being the basline speaker for these aspects.
Eminence Legend M12	This speaker is also on the Eminence Cross Reference as being a replacement. I have heard this one is like JBL speakers and has a lot of highs. Ear Candy Cabs states that it is well rounded and good for metal and rock with a top end sting and sizzle. Interesting, but personally I like less sizzle and smooth highs. Also at around $60 or so street price, I think there are better options.
Celestion Vintage 30	Some people swear by this speaker for everything. A whole lot of people love this speaker in this amp as well. A few say that it has too much bass and will shake the cabinet apart. What I do have is an Avatar 2x12 open back with a Celestion G12H30 and Vintage 30. Running this amp through really brings out the bass, but it does sound good. Personally I like Vintage 30's for a lot of things. I will probably pull the speaker out of my 2x12 to try out. With 100dB SPL and it mix-cutting abilities, this will definitely be a candidate.
Eminence Governor	This is from the relatively new line of Patriot and Redcoat series of speakers that have just been getting awesome reviews. It is supposed to be similar to a Vintage 30 without the bad stuff and more good stuff. A lot of people rave about this speaker. My only concern is that the extended low end my cause some troubles. I am already planning on replacing a couple G12H80's that are mixed with Eminence V12's in one of my 4x12's. So this one will definitely get tried out. At 102dB SPL it should be loud. But there is also not a single bad review for this speaker.
Celestion 70/80 Celestion Seventy-80	This comes stock in many Randall amps. I know it is also standard with the Traynor YCV40 which to me seems like a better version of the HRD. These are pretty cheap ($30) and supposed sound pretty good with this amp. I am not sure if I will try this one. The Traynor YCV40 sounded way better with a Vintage 30. I figure for $20 or so more dollars I can get a much better speaker.
Celestion G12H80	I believe that this speakers comes standard with Line 6 Modelling amps. Avatar Speakers is having a blowout sale on these. I really don't care for them much in a 4x12 (mixed with Eminence V12's), however since I already own a couple, it is worth trying out. In general many think this speaker is kind of steril. That is probably true since it is supposed to cover pretty much all styles of music. I find them to be harshly bright and not cut through the mix very well.
Eminence Screaming Eagle	This is one from the new Eminence Patriot series. It comes recommended for the HRD since it relaxes the bass some. It is also supposed to be a pretty versatile speaker, but kinda bright. I think I will pass on this one.
Reverend Alltone	A lot of people love this speaker in their HRD's. However most of them are more interested in classic rock and other lighter stuff. From what I have read, this speaker does not like Metal. But it sounds like a great speaker and the price isn't too bad. This one is a touch choice. I think I might see if I can return it if I don't like it. It is supposed to be a hot-rodded Jensen.
Jensen C12N	This speaker came out with the HRD Limited Editions. It is supposed to give a more traditional Fender sound. From my past experience with these, they are pretty bright and chimey. My concern is that they may not do Metal well and be a bit too HiFi. I think if I decide to go this route, I will get my hands on a Reverend AllTone first.
Eminence Swamp Thang	Recommended as a replacement by Eminece for the HRD. I am not so sure about this. Appearantly it is voiced to be bassy, so with the HRD it might be a bit much. I think I will skip out on this one.
Eminence Red White and Blues	This is supposed to be the American Cousin the Governor. Appearantly it is not recommended for Metal. Definitely considering this one if some of the others don't work out.
Eminence Tonker	This one looks interesting. Many people like this speaker but not many decided to continue using it. Instead many of them switched to another in the Eminence line. Ear Candy Cabs in particular really like this speaker as being the one that can do anything in their cabs. It gets their highest review. Some don't like it with distortion because it is too piercing. It has the highest powerhandling of any of them and seems interesting. I will consider this one in my purchases.
Eminence Private Jack	Supposedly similary to a Celestion Greenback, this speaker was chosen by many in 4x12 cab configurations. This one looks interesting and supposedly is popular for Fender and Vox replacements. Appearantly the original Greenback is pretty bad in Traynor YCV40's. I am thinking I might avoid this one.
Other Speakers	Of course there are a ton of speakers out there to try. Weber, Tone Tubby, othere Celestions, Jensen, etc. These ones above are the ones that really stood out and that there had been some discussion about. I have a Jensen MOD 70 in my Behringer V-Ampire and a couple Eminence V12's that I might try for fun. But at the same time I don't want to spend all my time swapping speakers.
So I think I will go ahead and buy an Eminence Governor and an Eminence Tonker. I figure if I don't like the Governor with this amp I have a home for it in a 4x12. If I don't like the Tonker, I can sell it. I have a feeling that the Tonker may fit better. Even though many complain about the abundance of bass, I think that it is good for a live setting to give a fuller sound. I am considering getting a Reverend Alltone with their 14 day return policy. But I feel bad breaking in a speaker and all and then sending it back. Maybe I can just order a "used" speaker and go from there.

Tube Research It amazes me that there are still many tube brands. I would say that most brands like TAD, GT, Ruby, ENGL, Fender, Mesa, etc. are just testers and re-labelers of tubes. But even with that, there are still a surprising number of manufacturers like JJ/Tesla (Slovak Republic), Shuguang (China), Sovtek(New Sensor, Russia), SED (Russia, formerly Svetlana), Electro Harmonix (New Sensor Corporation, Reflektor factory, Russia), Svetlana (New Sensor Corporation, Reflektor factory, Russia), Ei (Yugoslavia), and some of the re-labelers have factories make custom tubes for them as well. Once again all of these work for different people, in different amps, and for different styles. Fortunately tubes are a bit less expensive and are relatively easy to swap and test with. NOS Tubes - So I am not going to try NOS tubes here. I know that so many people swear by them and that they are more reliable since built for the military and such. However, even though I agree that many of them sound great, they are expensive, often hard to find, and often not worth it to buy and experiment with. Powertubes wear out with use, no way I will ever go NOS with Powertubes. Pre-amp tubes, I think the only reason to have NOS tubes around is to compare with current production tubes. Even though pre-amp tubes last longer, NOS to me just makes me nervous. I would rather sacrifice a bit of sound for the piece of mind of easily finding replacements. Especially since my amps do see a lot of use.
Power Tubes
Sovtek 6L6GC/5881 WXT (stock)	This is what comes stock with the HRD. It is relabeled by Groove Tubes (GT) and biased cold by Fender. These have a really high reliability being originally designed for airplanes. To many they aren't great, but they aren't bad either. The ones in my amp are surely worn out. But also I have other amps that take these, I will probably buy them for testing and baseline comparison.
Electro Harmonix 6L6GC	From what I can gather, this is pretty much an improved Sovtek 6L6WXT+. The Sovtek is supposed to add 20% more output. Both are modelled after the RCA Blackplate. I use these in my Sovtek MIG 100 and love them. Others have had great reviews about these in the HRD. Since I have some, these will definitely be tested.
JJ/Tesla 6L6GC	Now I have never used these tubes but so many rave about them. Of course there are those that don't like them. They are supposed to be a bit less bright and be harmonically rich. A trusted guitar tech friend of mine swears by these and eurotubes recommends them as well. I figure I will get a quad to try in my Sovtek MIG100 as well. From picture inspections, these seem to be the same as the ones relabled by the Tube Amp Doctor (TAD).
Shuguang 6L6GC	These are relabled by Ruby and are supposed to be of pretty high quality. My ENGL Powerball has these in its poweramp. I will just steal these to test with.
SED 6L6GC	I have used these in Mesa amps and they are pretty nice. Definitely on the vintage side of things. Many reviewers agree. I have heard that these don't do so well in the HRD. I think they would do better if I was more interested in a classic Fender sound. But I think I will steer clear of this one. Not that it is a bad tube by any means, I just have little confidence that it will work for me.
Svetlana 6L6GC	These are the new tubes made by New Sensor. They are supposed to sound pretty good. These are relatively new and I haven't heard much about them. I think I will hold off on these for now. Maybe next re-tube.
6V6 Tubes	Many people have tried using rugged 6V6 tubes to lower the power and get earlier break-up. I think this would be great if your focus was more on the distorition. For my purposes however, I will stick with 6L6's.
7581 or KT-66 Tubes	7581 tubes are supposed to have a higher power handling but similar specs to 6L6GC. The problem is that they are only NOS. I couldn't find any that were in current production. KT-66 tubes are supposed to be good as well. However I have also read that you are better off getting a nice 6L6 versus KT-66. I think I will stick with 6L6's for my purposes.
Preamp Tubes
Chinese 12AX7A (stock)	So far I have been happy with these. I might try a set of the latest generation ones since they have been getting great reviews lately. But these ones in here have been reliable and still work great.
Sovtek 12AX7A	This is the standard tube for most guitar amps. Personally I have never been excited about these tubes. I have a few that I will probably try out. This is probably more just a standard to compare against.
Electro-Harmonix 12AX7EH	These are supposed to be very balanced, have low noise, and very low microphonics. I have a set of these in my Sovtek MIG100 and Fender Champ. They are very clean and clear, but a bit gritty with OD. Since I have so many of these, they will definitely be tried out. With the HRD, they supposedly work well in all positions and best as the Phase Inverter.
JJ/Tesla ECC83S	There are many people that swear by these tubes. There have been reviews that they are darker and to some lifeless. However there have been many reports that these tubes really help the drive channel on the HRD. Appearantly the high gain versions are supposed to sound better. Also they are supposed to be muddy as a PI. I personally have no experience with these tubes. But I will buy some to try.
GT 12AX7-M	This is Groove Tubes Mullard copy. I have heard some great things about the tone of these tubes in anything but high gain. I have also heard bad things about reliability of the earlier runs. I will probably buy one for V1 to try in other amps as well. My only concern is that it might be too rich sounding for pedals.
Ei ECC83