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Sheik Yerbouti

I've got a bunch of newbie questions regarding vjr head and cabinet

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I have this:

478579.jpg

 

and this:

2337189789_8b3522ab04_b.jpg

 

I love the sound of the amp, and the guitar is wonderful, but I have a Zoom 505 II pedal for all effects and honestly, it's not cutting it. I'm on a pretty tight budget and have read some really good things about the BitMo Trio mod, and wouldn't mind giving it a shot but

1) I have no electrical tinkering skills :-k

2) I have no idea how to mod it :-k

3) don't want picture #1 to be dead :-&

 

So how hard is it for a total novice to do this mod, or for that matter, even replace a tube?

Seriously, I am that uneducated electrically speaking. I can build up a computer from scratch, but no idea how to look at a schematic and know what the crap I'm looking at.

Any help/suggestions/ideas would be really appreciated.

And feel free to point and laugh at the newb.=D>

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not hard but read the Valve Junior 101 thread here, some of the links send you over to www.sewatt.com where most of us modd'ers lurk. It's a free sign in account over there.

 

Then read the FAQ thread there.

Best thing you can do for yourself is to buy your soldering iron and some 60/40 resin core solder and buy some 10cent resistors and pratice soldering them together.

Bigest mistake any noob makes is the way they solder things together...

And keep reading those faq's so you can understand what you want to mod first, there are way too many mod's to start off with.

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It's EXTREMELY easy to mod the VJ, but don't dive in blind man. Here's my recommendations:

 

[*] Get a friend who can solder and kind of knows electronics, and have him sit with you. Do the work yourself, with guidance. Don't pay someone to do it for you, maybe let your friend do the first solder joint to show you (it helps to see it).

[*] Get some JJ tubes. I use a matched/balanced 12AX7 gold pin ($22.50) and a #35 JJ EL84 ($10) from Eurotubes. They'll tell you what to get if you tell them what you want to hear. Non-residue contact cleaner spray on the pins and wiggle the new tubes in and out a little when you install 'em. These will last you a while, but cycle them out every 6 months (more often if you play every day and play a lot), they're cheap.

[*] If you like that, consider a Hammond 125ESE OT upgrade. It's not as significant now with the V3 OT, but it'll put on a little polish. It's a $50 upgrade. solder some spade connectors to the wires going to the board, rather than soldering this one to the board itself.

[*] If you want to go all out, look at a marshallization mod and figure out (or ask) how to combine it with the BitMo Trio. Get a kit online, some places have higher quality full circuit replacements with better caps and resistors to get a more crisp, clear sound; again, $50-ish.

 

Definitely do the first two, it's well worth it for BitMo Trio and the tubes are cheap. The Tube Store also match/balance tests TungSol 12AX7 if you want to try those (different sound). BitMo Trio is $50 to add new features, and retubing is just a $30 maintenance cycle (like an oil change) but you're stepping up to better parts (like higher quality brand oil instead of gas station brand).

 

A Hammond 125ESE will give you the best bang for your buck here ($10 more than a 125DSE), but it's not a super amazing change on a V3 like on a V2. It still adds some shine from what I hear (I haven't done this YET but I will). The whole rebuilding of the board with high-quality components will similarly add some shine. This is basically $100 spent improving the sound a little bit; you may not want to do that. (Notice I ordered the above suggestions in what I believe is order of diminishing returns?)

 

I just got a Weller 40 watt soldering iron ordered, suggested by some fellow on here (m-theory?). It's important to have a GOOD iron to do this!

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I don't mean to argue blues points.. all were good.

 

still, I recommend a plan..

start with paper!

what do I want it to do...... then find out from experienced people if that can be achieved, how much it will cost, how hard it is to do.

 

after that.. look at the mods that people talk about, and listen and ask and learn..

 

for instance.. you want your voltages correct.. but you don't want to mess anything up.. so perhaps instead of going full guns for a monster amp, you might be better off just using some standard mod approach, with fewer changes.

 

changing a tube is just pulling it straight out carefully, with light wiggling to loosen it as you go..

and making sure it all lines up when you put it back in.

 

some mods are very easy and make a fast dramatic improvement.. but do nothing to prolong tube or component life, or help to get that sweet spot tone.

 

so consider the aspects.

 

safety

cost

tone

difficulty

 

and start to, later on, get those ranked together in your mind..

 

the result may be.. an hour of soldering and a 100% better amp!

it may not be right up there with the guys at sewatt.. some of them have done five vjs, scratch builds, and many other amps.

 

My vj was my first amp mod, too.. it's doable.

 

and by the way. very nice guitar and they look great together don't they?

way to go!

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Thanks TWANG & blue! I think I'll replace the tubes and then go from there. I read that the head can still give you a good shock even after it's off. Of course I will unplug it, but is there a 'wait time'? to fuss with the tubes?

Thanks again, yea, I do dig the vs on that Casino.

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Twang makes a multitude of excellent points. One thing I missed on was tube life and voltages; you want to rebias that amp (and it will need it after any mods or OT change). This is inherently not safe! Use a rebiasing tool from Eurotubes and/or have a friend or tech do it! The tool goes into the tube socket and takes the measurement for you, instead of you screwing around with a powered-up, multi-amp circuit (I told you, not safe. Doable, if you're careful, but... a lot of things have to be done that are freaking dangerous).

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I turn the amp off and keep playing, the sound goes in about 15 seconds. The tubes are hot anyway, you probably want to let them cool off. UNPLUGGING THE AMP IS THE OFFICIAL WAY TO REMOVE POWER FROM THE CIRCUIT BY THE WAY.

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sheik nope just let them cool off.. they'll burn yer fingers!

 

jj ecc83 aka 12ax7 is good tube.

the eh 12ax7 in my combo works in both my heads well, too.

 

the sovtek el84 gets knocked, but I actually like it. it's tough, too.. and a great spare to have around.

jj's el84 is the most common upgrade and a very excellent selection.

 

my next power tube will be a TAD.

 

tubes don't like hard knocks.. store padded.. don't roll across hard surfaces, etc.

 

 

TWANG

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sheik nope just let them cool off.. they'll burn yer fingers!

 

Indeed, I cook steak sometimes at the temp the tubes get to (yes, that low). (I have of course messed with my tubes directly after an hour of hot playing; I'm flame proof, you're not)

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Just sort of guessing here, but it looks as though your head is a V3, which means that some of the modding has been done by the factory already, so that's cool. Based upon your geet box, it would also appear that you probably favor jazz and blues, which means that the ridiculous gain from these amps in stock form is really way over the top. You're probably also hearing some sloppy, flubby bottom end...those types of guitars tend to be rather dark, and HB pups in general can overwhelm these amps rather quickly with bottom end.

 

I wouldn't suggest that you go nutso with mods off the cuff. You should get the bias set up right, and you should also consider swapping C1 and C2 for something smaller...maybe start with about 1/2 stock value and see what it sounds like, to tigthen up the bottom end, and also consider swapping C3 and C4 with 1uf, for more of the same effect. Between those caps, you'll be able to dramatically clean up the bottom end.

 

There are several places where you can shave off some gain, but the easiest places to start would be to swap the 12AX7 for either a 5751 or a JJ 803S, and/or replace the volume pot with an A500K.

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Just sort of guessing here' date=' but it looks as though your head is a V3, which means that some of the modding has been done by the factory already, so that's cool. Based upon your geet box, it would also appear that you probably favor jazz and blues, which means that the ridiculous gain from these amps in stock form is really way over the top. You're probably also hearing some sloppy, flubby bottom end...those types of guitars tend to be rather dark, and HB pups in general can overwhelm these amps rather quickly with bottom end.

 

I wouldn't suggest that you go nutso with mods off the cuff. You should get the bias set up right, and you should also consider swapping C1 and C2 for something smaller...maybe start with about 1/2 stock value and see what it sounds like, to tigthen up the bottom end, and also consider swapping C3 and C4 with 1uf, for more of the same effect. Between those caps, you'll be able to dramatically clean up the bottom end.

 

There are several places where you can shave off some gain, but the easiest places to start would be to swap the 12AX7 for either a 5751 or a JJ 803S, and/or replace the volume pot with an A500K. [/quote']

 

Thanks, I like blues, rock, and would love to learn jazz, I am cool with swapping the tubes out but all the other stuff you suggested went way over my head.;)

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M-theory hits the nail on the head.. and good call on your setup, too.

 

The C1 etc are capacitors.. and they will do just as he said.

C3 and C4 at 1uF really made the grade for me.. and guess what.. I use P90s, too.

 

Basically each as two legs which solder through holes in the board.. you remove the originals, and solder in the new value caps.

Be forewarned you have to have the right values.. that's why the reading comes in handy.. and asking before you buy parts.

(cheap.. everythings well under a buck most times.. .24 or .56 cents!)

 

I'm a newbie.. and pretty clumsy at that. But after doing my first mods on a head, I did a combo today in about an hour.

 

some of the voltages on the vj are pretty high.. he wants to get you into the 310V sweet spot.. save your tubes and make them sweeter clean or distorted.

 

step by step you can find out.. and it's doable.

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Thanks again, this just makes me feel so incredibly stupid. I got the back cover off, can see the tubes, but have no idea how to remove the base they're on. I think I need to find a local guy who's done this and is willing to lend a hand.

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The top of the amp has a bunch of circles. Pop them off with a 0.60mm Dunlop Tortex or similarly hard medium pick. Unscrew the screws, slide the head out, flip it over. Remove spring retainer and shield (twist off) from the tubes, pull.

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this just makes me feel so incredibly stupid.

No need to. You're amongst friends, and everyone was a noob at some point, regardless of their current experience level.

 

The tube just pull straight out, but you've first got to remove an RF shield from the 12AX7. It's a metal can-shaped cover that screws off in one short counter-clockwise turn. Then, just carefully grab the tube in your fingers, gently wiggle it very slightly back and forth while pulling it downward to remove it from the socket. The EL84 comes out the same, except there's no shield on it.

 

There's no harm in feeling uncomfortable with it, and wanting to farm it out. This stuff isn't difficult, but it does require a level of patience and even a degree of courage that some just don't want to test. There's nothing wrong with that. If that's the case, ask around to friends you know who play. I'm willing to bet that at least one of them either does this stuff themselves, or knows someone who does.

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No need to. You're amongst friends' date=' and everyone was a noob at some point, regardless of their current experience level.

 

The tube just pull straight out, but you've first got to remove an RF shield from the 12AX7. It's a metal can-shaped cover that screws off in one short counter-clockwise turn. Then, just carefully grab the tube in your fingers, gently wiggle it very slightly back and forth while pulling it downward to remove it from the socket. The EL84 comes out the same, except there's no shield on it.

 

There's no harm in feeling uncomfortable with it, and wanting to farm it out. This stuff isn't difficult, but it does require a level of patience and even a degree of courage that some just don't want to test. There's nothing wrong with that. If that's the case, ask around to friends you know who play. I'm willing to bet that at least one of them either does this stuff themselves, or knows someone who does. [/quote']

 

The odd thing is, I have zero issue's with modifying a computer (overclocking cpu's, gpu's, RAM, installing a new cooling system on a video card, etc.). BUT, I didn't feel like that at first, I was scared about upgrading RAM (this was a LONG time ago, and you needed to adjust jumpers on some motherboards](*,) )

So yea, little by little, I'll dabble here, tinker there, and hopefully the head won't have an ozone smell coming from it or worse.

The tube's seem pretty straight forward, it's the schematics that I don't like.

Anyway, thanks again man. Much appreciated.

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The worst you'll get is you'll melt right through it with a 200 watt iron, or you'll jack a speaker into the amp while it's on and hot and speakerless and the OT will catch fire and then explode. If you avoid doing anything stupid you should be fine.

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In the head it's hard to get the tubes back in without pulling the chassis. I tried' date=' I'd need a mirror to do it. They go in only one way.[/quote']

 

If you unscrew the front panel and put the back panel on the front of the amp, you can see the socket from the front. Makes tube swaps pretty darn easy, even with a Hammond 125ESE.

 

Gil...

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I should add, with regard to tube swapping, to be careful for proper pin alignment, or you'll bend them all to hell trying to put them back in. Just be wary of where the gap in the pins is aligned as you pull it out, so you know how to position the new one going back in. It is immeasureably easier to replace tubes in the head with the chassis out, or, to do what Gil suggested. Once you've done it a couple times, though, it's a breeze, because you'll get a feel for knowing when the pins are lined up correctly without looking.

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Sheik -- I'm another budget minded "newbie" Jr. owner (but a seasoned garage player on some crappy solid state amps) so maybe you will want to completely ignore my comments. I've had mine, also a new ver. 3, about three months and overall it is fabulous - - but can be a little better in a couple of ways for me as well. I researched the Jr's a lot before buying it instead of the Blackheart (and even more after buying it re. the multitude of tone tweeks) and here is what I have found:

1. The ver. 3 (which we both have) is a much improved animal from the 2 prior versions.

2. Most of the mods out there were needed for the 2 prior versions but not so much so for the ver. 3.

3. BEFORE HACKING INTO A NEW VER. 3 JR:

A. Read "Smokestack's" topic thread "Valve Jr. reality check" on this forum, keeping in mind that most of the "experts" on this forum have the older versions (goes for any topic thread found here), so their opinions are largely based on the earlier, lesser versions.

B. The ver. 3 is still a bit harsh at the higher volume setting -- a simple tube upgrade fixes most of that -- try a Tung Sol reissue gold pin 12AX7/ECC803S or Slyvania 5751 for preamp and the JJ/Tesla EL84s [i]("m-theory" is right on target with this advice, I'm just doing the favor of passing it on[/i]). These have smoother tone and better mids/lows without sacrificing the good crunchy highs for solos.

C. BEST TUBE BUY on internet -- Virginia Tube Audio -- dba. "snpower" on eBay (sells the JJ's for $8.00 ea.)

D. TRY a cheap pedal or two, or better yet, a Line 6 POD. Mine responds so well to the tonal variations that I can adjust with my Keeley/Boss BD-2 or even better my old ver. 2.0 POD. In fact, I would say that the $100 you will spend on a good used POD is far better spent than 50 here, 35 there, etc. etc. on this mod or that mod... PLUS YOU CAN ALWAYS USE THE POD WITH ANY OTHER AMP OR RESELL IT FOR WHAT YOU PAID IF YOU REALLY DO NOT LIKE IT. (You can't return those soldered capacitors and kit mods, plus you've voided your Jr. warranty by hacking it.)

 

One final word: I like to practice the high gain settings at low volumes to nail them first (and only then do I want to bring down the house -- i.e. Jr's true tube nirvana is reached once the volume is loud enough where you can no longer hear the neighbors. If you feel the same, consider investing another $100 in this little gem the "TUBE CUBE". It's an L-Pad attenuator that works as well as a THD hotplate ($299) and has added benefits like the ability to plug into different ohm rated speaker cabs all at the same time.

Hope this helps you make the decision that is RIGHT FOR YOU!

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Cool, thanks again all. Like I said, I think I'm going to swap the tubes out. I honestly don't know what tubes are in in it now. And how can I tell if I have a V3. I really appreciate all your advice and coddling of this newb. I've always loved guitars, and now my rebirth of that passion (now that i can afford 'decent' stuff) has only made it stronger. I'll check into that place for tubes.

Thanks again

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