i dont know much about tube, so what kind of tubes would yall recomend for a valve jr combo? what does what and sound like what? please explain why i should get which tubes. thanks.
A 12AT7 in an Epi Valve Jr is pretty nice. A 12AY7 gives you an even better sound in my experience though.
The Electro Harmonics 12AY7 is not bad. A NOS RCA 12AY7 is even better as it gives a much better sound and also adds a lot of warmth, it is however much more expensive.
I would avoid the 12AU7 as it will cut the gain back by way to much and the amp will lose all it's liveliness.
The 12AY7 will give a better sound than an AT, even with the lower gain because of better transconductance. Might try a 12DW7 that is 1/2 12AX7 & 1/2 12AU7.
Try a 12DW7 in the phase inverter position which is usually the preamp tube closest to the power tubes. It will fatten tone for harp in some amps. Works great in the Blues Jr.
I like JJ Tubes which you can get from Eurotubes on the web. They use European designations, but it's not hard to correlate to the the equivalent American designation. Bob Pletka, the owner, is pretty knowledgeable about tube swaps to voice guitar amps for harp and he can provide excellent advice and suggestions.
A 12DW7 won't work very well in an Epi Valve Jr as it only has one pre-amp valve/tube. A 12DW7 or a 5751 works well in amps with multiple pre-amp valves/tubes.
Remember this when retubing: if what you use sounds good to you when you play within 3 feet of the amp, often times when you stand further away, it often sounds like crap because definiton gets badly lost and too often making certain amps harp friendly is too often an excuse for not getting tone, chops, and resonance acoustically first. ---------- Sincerely, Barbeque Bob Maglinte Boston, MA http://www.barbequebob.com CD available at http://www.cdbaby.com/cd/bbmaglinte
Jon-did you do the Randy Landy/Lone Wolf mods on it? If so, I know he recommends the 12ax7. also, in case you weren't aware, the same name tube, but a better-quality one, such as a NOS one will generally sound better tone-wise than the stock, with little or no change in gain. ---------- Todd L. Greene, V.P.
I have a stable of old miltary-stock 12ay 12at and 12autubes...good to keep handy for quick gain-taming. But, google the gain chart(I've seen them before)for a comparison of how much percentage of gain each variant will give you. ---------- Todd L. Greene, V.P.
I use a 12AY7 in my Epi Valve Jr and i'm pratty happy with it. I modified the circuit slightly, but that shouldn't make a difference in this case. 12AT7 tend to be a little harsh, but that might vary between manufacturers. DONT'T use a 12AU7 in your Valve Jr! It might kill the amp. The 12AU7 makes two specific resistors run out of specs (yes, I validated that). Personally i think the amp gets to weak with it anyway. DON'T use a 12DW7 either, it will cause the same problem as the 12AU7 and i don't tkink it will work well either without some rewiring iirc the circuit.
Another word about 12DW7 as phase inverters (jon, this is not for you, the EVJr does NOT have or need a phase inverter): This tube will do well in SOME amps if placed in the phase inverter position. However there are quite a lot of different designs of phase inverter circuits, and in some of them this tube will do perfectly wrong. Even if it works, the way in which it works can differ enormously from amp to amp. It might just reduce some gain or it might make the power tubes run very uneven adding distinctive distortion, etc. But anyhow it's never a good idea to put a 12AU7 or a 12DW7 in place of a 12AX7 without making sure it won't do harm on your amp.
Well... Lots of bad advice here. First of all, the notion that working on your amp is an "excuse for not getting tone, chops, and resonance acoustically first" is utter nonsense. If you want to sound good amped, you need to play amped from the start. You also need to learn your way around a tube amp, and there is no better way to do that than trying different components. Ignore those who whine about young players using an amp.
As for tubes, a small 5-watt amp can't afford to lose too much gain. If you decide to change the preamp tube, I'd recommend a 5751 or 12AY7. The AU7 is too wimpy for that amp, and the AT7 is a terrible tone generator. In fact, it draws so much current it is not really interchangable with a 12AX7. It is meant to be a Phase Inverter or to be used in high frequency circuits such as old TVs. To me it sounds shrill.
My favorite 5751 is a NOS JAN Philips you can get from Tube Depot in Memphis (and online) for $20. My favorite EL84 tube for harp is the inexpensive, standard Electro Harmonix. It is a tad darker than most others. I used it in my project Fender Pro Jr. I'd advise you to avoid most NOS tubes; way too much money for very little improvement.
well i said it before an ill say it again. guitar center sucks. i just drove all the way there for nothing. the guy looked at me like i was crazy for asking for a 12AY7 tube an he say he cant even order it. like it dosnt even exist. i really dont think im going to ever go there again. im ordering every thing online from now on. i even went to this other music shop that sells guitars an mainly tube amps an he didnt even have it. an he rebuilds amps all the time. waste of gas and time. ----------
Vacuumtubes.net is a good source too. I'm running JJ's in my Epi but the old RCA's are major bang for the buck. I think some tubes get there fame for there hifi qualities and that doesn't transpose into the amp world.
Yep NOS is new old stock. I agree with Rick that NOS is overrated (and with mosteverything else he wrote).
Those giutar stores just don't need 12AY7. They're very uncommon in guitar amps. They have 12AX7 for tone and gain, 12AT7 for phase inverters and occasional driver puropse and 12AU7 for phase inverters and cathode followers, but there's no demand for weird harmonica players tube lusts ;) You get better products at specialized online tube stores anyway.
Last Edited by on Jan 16, 2010 4:39 PM
Sounds like the BS I have to deal with here when I go tube shopping.
I found that audiophile and hifi stores are more likely to carry a better variety of tubes than most guitar stores.
I agree with Rick's post.
I also find 12AT7's HORRIBLE for tone in ANY amp. They are meant to be utility tubes used for reverb or an additional gain stage. Absolutely crap for tone in general.
And 12AU7's are a joke for harp/guitar amps. They are meant for hifi systems please.
The best sounding tubes based on my preferences are: 12AX7 5751 12AY7
You don't need NOS. One of the things that nobody has mentioned yet is that your amp can feedback uncontrollably if your preamp tube is microphonic.
One way to tell is how long the black plates in the tube are. The longer they are, the more likely they are susceptible to being microphonic. So short plates can be an indicator of a very good thing.
Gain values alone will not slay the feedback demon.
NOS tubes in general have been tested and usually are not as microphonic. So they may not be that much of an improvement for tone but they may cut down a lot of feedback. Though if you have the right kind of setup a NOS tube could indeed dramatically improve an amped tone.
I find EHX and JJ tubes to be the best bang for your buck. They are consistent enough in quality compared to all other brands. You will find that the pros who don't use NOS tubes will gravitate towards these brands.
Good luck and have fun on your tube tone journey. :)
thanks for the info. feedback is not an issue at all with me. im just trying to reduce the gain an clear up the muddyness of the amp with some cleaner better tone. ----------
5751..military grade, ruggedized low microphonics variation of the 12ax7 with about 70-75 % of the gain. It's the one I landed on when i had several to test from a guitar playing friend. Gave me higher gain before feedback and easier access to the dirty chicago sound. I have found my amp to be pretty bright, not muddy, but mine is the head and I use jensen 12 inch speakers with it. The 5751 mellowed it out a little from the brightness....speakers make a big difference too. To my ears, more than the tubes. I just EQ out the brightness i don't want. For my guitar, I don't eq it at all.
Last Edited by on Jan 16, 2010 6:10 PM
But it seems I'm in the right place right time i guess,,Downunder not much to choose from regarding custom Harmonica amps,,Yep i got a Fender Blues Junior USA mod,,i did the Google thing serched all things Fender Blues Junior,,Rick i found your web Page very helpfull,,so being an Old rev head my thoughts where that i knew that i didn't real matter what carbies i put on my Car to make it go faster even though there was a little boost in power but massive fuel costs and not realy running to full potentinal,,i realy needed to fix the motor first then the carbies would do there job....you may be able to help me out or Other Bro's with there prefferd tube combo's..this post is getting to long i will get back to you's soon tell you of my current mods
I don't entirely agree with you about playing amped up from the start--but then again, I did that, and I've got tone. So maybe you're right. But I also did a HELL of a lot of acoustic playing in resonant cavities, mostly public bathrooms, under bridges, etc, so maybe you're not right. Learning how to work with an amp and how to cup and work with a mic is crucial, though, so maybe you're right.
Maybe I'm undecided. Or schizophrenic.
In any case, I'd never heard of Tube Depot, so your tip, when I checked it out and visited the webisite, blew my mind.
Really, we should meet there at some point and talk tubes, if you're near the Memphis area. Clearly it's a place I've got to visit. Thanks.
Eurotubes sells a preamp tube swap kit to voice the Blues Jr. for harp. If I recall correctly it consists of the European equivalents for a 12AT7 in v1, a 12AX7 in v2 and a 12DW7 in v3. Besides having lower gain factors for 2 of the 3 preamp tubes, these JJ tubes are also not as harsh sounding to my ear as the stock tubes that come w/ a BJ.
I sold my BJ when the Princeton Reverb Reissue came out, but I liked the JJs from Eurotubes that i put in my BJ when I had it.
BBQ Bob is right when he tells us that what sounds good in the living room at home may not necessarily sound good on stage. But the BJ I had was unusable due to feedback w/o tube swaps. And even w/tube swaps, it was still a pretty high gain little amp.
Btw, Ruby Tubes makes a replacement reverb tank for the BJ that is deeper sounding than the stock reverb tank which I always thought sounded a little tinny.
Last Edited by on Jan 16, 2010 7:12 PM
These are the mods done to my Fender Blues Junior & have only been done no less than 2 weeks back.. so Im still doing the tube swap thing myself,,It's a USA Fender so i had to change the input transformer got sick of useing a step down transformer size of half a house brick 6 times heavyer..Ok Here we Go fitted Mercury Magnetics Transformers input & output,,a 35 watt 10"G-Back Celestion,,Ruby tube reverb tank,,the output transformer is Multi tap i can use 4 8 or 16 Ohms Speakers..the only other mod I'm thinking of at the moment is swaping the EL84 sockets so i can use 6L6 valves..after reading the info above I'm now going to swap back to 12Ax7s get it back to normal and start again with the tube swap thing thanks for all the info above,,Bro's any info on Prefferd Fender tube combos is most welcome
Last Edited by on Jan 16, 2010 7:13 PM
A propos of not much, I thought I'd share the following woodshed video. It's NOT on YouTube; strictly for this forum. I'm playing in the home office through my recently-refurbished Kay 703 (Brian Amundson did the job), and I must say: the thing kicks ass. We're talking 4 watts, perhaps--much less volume than the HG2--but the tone is, in some ways, the best tone I'm capable of getting out of any amp. When I took it down to a local open mic, miked it up with my EV ND468, and did the one-man band thing for 15 minutes, I got offered two gigs after I got offstage and the guy who books the bar--Jay Lang, a local blues guy--kept talking about the sound of the amp. It took a lot of trust, frankly, to think that I could show up at an open mike session with a tiny amp and make it work, but it apparently worked. When you hear the tone in this video, you'll understand why. Small amps rule! On this point, Rick Davis and I are in 100% accord:
Adam, your tone is rippin'; Love that little Kay amp. It sounds like a Bassman Jr., or something.
I'm not in Memphis, I'm in Denver. I've been a regular customer of Tube Depot for years. Great company, excellent prices and fast shipping.
As for playing through an amp when starting out... I did not mean to imply that a young player should play ONLY with an amp. My apologies for being unclear. I encourage ALL beginning students who are interested in amped playing to buy a 5-watt amp (a Harpgear HG2, for example) and play it a lot. The only way to get good amped tone is to play through an amp. I've found that it *HELPS* students get better acoustic tone as well.
Here is a short sound clip (dry, no effects) of my little 5-watt 1971 Fender Champ amp. It has slightly more grit than your smooth Kay amp. The tubes in this amp are a JAN Philips 5751 preamps tube, NOS RCA blackplate 6V6 power tube, and NOS Sylvania 5V4 rectifier. This amp has been upgraded with paper in oil caps and voiced for harp. It has a good-sounding line out, so I gig it frequently. Great tone, and it weighs only 21 pounds!
@congaron: ya my valve jr sounds bright too but muddies up when you turn the volume up. for my set up i get the best tone around 10 O'clock. anything past that it gets too distorted. i have a jensen 8" speaker in mine. but my effects set up takes away alot of the unwanted brightness giving it more mids an bottom end. ----------
The snakeskin 5F2H amp that I use as my main gig rig is one of the best sounding harp amps I've ever heard, but the tubes I run in it are pretty run-of-the-mill. The preamp tube is the same JAN Philips 5751 I use in the Champ amp.
The power tube (only one, this is a Class A 10-watt amp) is a regular new production Tungsol 6L6GC STR short bottle. The rectifier is an older RCA 5Y3, but nothing special.
If you are not having feedback issues, there is no real reason to lower the gain of your preamp section. I'd concentrate on the power tube. Try EH, JJ, and new production Mullard; see what sounds best. These tubes are reasonably priced and readily available.
Steer away from expensive NOS tubes. The vendors will all swear their tubes will make you sound like Big Walter or Kim Wilson, but it's a scam.
Well, yes and no... Let's back up for a minute. If your issue is muddiness in your tone, you might try a different speaker first. My opinion (and this is only my opinion) is that Jensen "Vintage" speakers are not the best harp speakers. You might think about trying a low-priced Weber alnico Signature series speaker with a smooth cone. (I think the alnico magnet will fit in your cab, but I'm not certain. Ask the Weber people.)
If you replace the power tube, yes, replace it with another EL84, but try different makers. The tones won't be dramatically different. The BIGGEST tone difference you can make in your amp is a speaker swap.
Hi..Jon & Bro's thanks for your replys to my question via Jons Post..wow my heads spinning..what i can see is the best tubes 4 my BJ are 5751 & 12AY7..and a Milk crate vist Ricks web page it might be all you need..you mention your happy with it's Sound..
Marble Amps sells a custom jensen speaker which is is think a C8H with a very smooth cone. It's the same they use in their "Max" model and other harp amps. It sounds great! I have one in my Epi Vapve Jr and one in a 2x8 cab, too. IMHO one of the very best sounding 8" speakers for harp and reasonably priced too.
Last Edited by on Jan 17, 2010 12:29 AM
A few things to bear in mind are: The tube swaps for a Blues Jr will not work in an Epi Valve Jr as it's a totally different amp with different circuitry.
The Epi Valve Jr tends to sound good with a Weber Sig 8 in it. It does however have a tendency to sound a little "bright". I prefer the Jensen C8R in it myself (but it's all down to personal taste).
A Electro Harmonics 12AY7 would be the best pre amp tube (good enough for HarpGear amps!), NOS tubes will give a slightly better sound (well in the case of the RCA 12AY7) however the improvement isn't really worth the cost in this case. A good EL84 tube should improve the tone a little as well.
Of course acoustic tone is the biggest factor when "amping up". If you don't have warm, full, fat tone acoustically to begin with, then no amp in the world is going to give it to you. An amp will make you sound like you, just louder with some overdrive in the mix.
But my best advice would be to sell the amp on and buy a HarpGear Rock Bottom or HG2, Kalamazoo Model II or alternatively buy a 5F1 amp kit and make your own "Champ". All of those options will sound infinitely better than the Epi Valve Jr.
Hi Jon, Have you tried adding a tone control to your Epi? I have a Harley Benton GA5 which is a Valve Jnr. in a different cabinet. This amp comes with a tone control but it is not very good, it seems to "colour" as against being bass one way to treble the other if you get my drift. To remedy this I purchased a "Brownface" tone control kit from Nigel Briggs at Alnicomagnet here in the U.K. The kit cost £12 (about $20) and it transformed the amp. Fitting time was about 90mins. For your side of the pond I think Randy at Lone Wolf does a similar kit.
Regarding Gain, I found that I was swapping tubes and testing pretty early in my voyage into the amp'd harp sound. I won't say tube swaps don't work, because they do. However, in my personal experience...eight months later i am using the stock tubes again except that the 12ax7 is not the electroharmonix one, but a fender tube.
I have no feed back issues whatsoever, even in a small room at high volumes. For me, acoustic tone, the right mic and cup has made more difference than any of the tubes i tried. I also tried speakers...many of them, since my amp is the valve junior head. I found the 12 inch speaker takes out some of the brightness I didn't like with an 8 or 10 inch speaker and puts in more bass. It makes my head much more "dialable" for the tone I want, using my digitech pedal as an EQ, slight delay and volume control only. You can't put back what isn't there, but you can certainly cut out what you don't like. For me, the brightness was the bigger issue. The 12 inch speaker gives me the tone i like. I also found a noticable volume increase when adding the second 12 inch, with even more bass and no further loss of treble.
I have mics that still sound bright through this combo, so I think for my setup the mic is what's causing the brightness, to a degree. For my guitar, the stock valve junior head with 2 12s is the sound i always wanted but thought I couldn't afford, so playing harp brought me to another level of joy on guitar too.
As for technique, mine makes more difference than any of the above mods here in my house and when i play out. I always play out with at least one 12, mic'd into the PA in case the sound guy thinks It needs a boost. At home, I don't care what I play through..they all sound good.
Last Edited by on Jan 18, 2010 9:57 AM
Jon, I recommend staying with the 12ax7 get a better grade tube if you want but you'll lose gain even with a 12ay7 Power tube the same I like EL84's in single valve amps but you can upgrade to better quality. I still think the Lone Wolf Mods are an improvement over the stock amp, mostly upping the filter caps and putting in the treble cut to better dial into the room. The more I got used to the amp the less I use the treble cut but it's nice to have if needed
I think this is where microphones and technique come into play. I can turn my valve junior all the way up without feedback and play really loud, dirty harp. As I reduce the volume, it becomes more of a crunchy, gritty sound. At around 9 o'clock it goes into the realm of trumpet or trombone, depending on the harp and gets less loud. By putting mine at around 2:30, I can get all of those sounds with my volume pedal and mic technique. The sound guy can control the volume in the PA, since I usually use just the 5 watt amp and figure all this out at soundcheck. With a 5751 in there, before i had ANY skill with an amp, I could turn it up much higher before feedback to access the dirty tones I didn't know how to make with my technique. Having the full range of your volume knob without feedback gives you more tone options on the valve junior.
