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valve senior head release update! Geez this is a popular thread!

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If you find you miss the clean tone of the 6L6' date=' but love the grind of the EL34 pushed too far, try some JJ KT77's. They're the best of both tubes, and made to be a direct swap out for the EL34. Tweak of the bias, and it's good to go same as any tube swap.

 

Gil...[/quote']

 

Kewl, thanks Gil!!!

 

I'm gonna try the EL34's first but I wil definately check out some KT77's,

looks like JJ has the best reviews and price on the KT's.

 

Also, I didn't know before 'googling' that 6CA7's are the US version of EL34's?

And EH sells both EL34 AND a 6CA7 tubes?

The 6AC7s have a bigger bottle and more gain from what I understand, maybe not what I need, IDK.

 

Also, do I need a triode matched 12AX7 for the phase inverter slot?

I've read where the EH12AX7s don't work as good in that spot, is that true?

 

Thanks,

JOS

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I can't imagine why someone might think an EH 12ax7 wouldn't work in a PI. They're about the same as a Sovtek 12ax7WA, and made in Russia by the same guys that make Sovtek, TungSol, and Mullard resissues. New Sensor owns all those brands and more. Maybe they just didn't like the tone!

 

Besides a matched triode in the PI is a marketing scam! Those tubes were made for critical calibration instruments, not guitar amps. In a guitar amp, a little imbalance is a good thing, since a perfect balance would self cancel all those sweet second order harmonics.

 

And matched power tubes weren't even available back in the old days. The more widely imbalanced a set of power tubes are, the sooner they'll distort, which means less headroom. The best you could hope for was that they were close, because the closer they are to a perfect balance, the more clean headroom you'll have.

 

But nature abhors a clean tube amp. PI's are not perfect, and neither are tubes. And as the tubes burn in, they'll each drift off spec a little differently and sweeten the tone with more even harmonics as they deviate from each other, but without being so far apart to significantly affect headroom. So buying matched pairs of power tubes is actually a good thing for the sake of headroom. Matched quads are even better, since you only bias once. When a tube blows, throw in the fresh set. When one of those blows, the remaining two will still be a good match since they're both burned in.

 

If you really want lots and lots of power tube crunch and don't care about clean headroom, you can avoid the upcharge for matched sets of tubes. Just split the difference between the tubes for setting bias current around 65 to 75% of max plate dissipation if possible, and just run whatcha brung!

 

Gil...

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I can't imagine why someone might think an EH 12ax7 wouldn't work in a PI. They're about the same as a Sovtek 12ax7WA' date=' and made in Russia by the same guys that make Sovtek, TungSol, and Mullard resissues. New Sensor owns all those brands and more. Maybe they just didn't like the tone! [/quote']

 

Hey Gil,

Yeah, I don't know where I read that, some msg brd where a tube head (can't think or find the model now but it was a more recent high gain amp I believe) was blowing 12ax7's in the PI slot and some others verified it and said that they found any of the New Sensor 12ax7s weren't good for that slot and are prone to failure.

I have 2 Tung Sol 12ax7s that I can try in the other slots, all the rest will be EH's. I also recently bought a pair of the 12ax7 Mullard re-issues but didn't really like them in my Cyber Twin so I might just sell them after I try them in the new So Cal.

I'll also try and contact Epi to get a schematic for the So Cal so I can know exactly what the V-slot numbers are, another guy on a msg brd said he did and they sent it right to him. Even though I've had tube amps for many years it's only now that I'm really understanding them and the differances between types/brands/etc...it's been a very kewl learning experience.

 

 

If you really want lots and lots of power tube crunch and don't care about clean headroom' date=' you can avoid the upcharge for matched sets of tubes. Just split the difference between the tubes for setting bias current around 65 to 75% of max plate dissipation if possible, and just run whatcha brung![/quote']

 

I'd probably prefer more clean headroom but I'll see what the So Cal sounds like when it gets here (should be tomorrow). That was my prob with the Cyber Twin, I experimented with preamp tubes to try to extend my clean headroom (Mullards, GT, JJ & NOS RCA 5751's) and found the EH's work best in that amp.

I also will look into the KT77's as per your referal if the EL34's don't cut it.

 

Also, what ohm do you recommend I run the So Cal at?

My Marshall 1960A cab has any option,

from 1 - 4 or 16 ohm mono input or 2 8ohm stereo inputs, which the So Cal has 2 8ohm outs.

From what I can gather the 4 ohm would be the best but I am considering the 2 8ohm configuration.

 

Thanks again Gil, you've been a great help to me!!!

 

peace,

JOS

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WORD FROM EPIPHONE:

VALVE SENIOR NOT SHIPPING UNTIL JULY!

 

loser-1.gif

 

Back to the drawing board.

 

I'm keeping my place in line though.

 

That's what a loser I am.

 

Where'd you get that info?

I'm getting ETA May 8th from my dealer.

 

And could someone please explain to me what GAS is?

 

Thanks!

 

 

/Anton

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Gear (or Guitar) Accquisition Syndrome G-A-S The affliction of every member of this forum.

 

Wedgie

not necessarily an affliction, but a disorder of sorts...

it's not a bad thing if you have money, but it's horrible if you don't. most members of this forum DONT have money, or they wouldn't be here, they'd be out buying stuff (or enjoying what they've bought) rather than contemplating how they might go about buying something in the future... or getting it past their wife... (any women here who can't convince their husband? i don't want to be sexist or anything, but it seems like a less likely scenario...)

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WORD FROM EPIPHONE:

VALVE SENIOR NOT SHIPPING UNTIL JULY!

 

loser-1.gif

 

Back to the drawing board.

 

I'm keeping my place in line though.

 

That's what a loser I am.

 

SWEETWATER LIES!!!!!!!!

 

I'LL HAVE THEIR HEADS FOR THIS!!!!!!!

(or just not buy anything from them... back to music123... of course, they don't have any 5751 tubes there, but that means i might as well get cryoset :))

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Also' date=' what ohm do you recommend I run the So Cal at?

My Marshall 1960A cab has any option,

from 1 - 4 or 16 ohm mono input or 2 8ohm stereo inputs, which the So Cal has 2 8ohm outs.

From what I can gather the 4 ohm would be the best but I am considering the 2 8ohm configuration.

 

Thanks again Gil, you've been a great help to me!!!

 

peace,

JOS[/quote']

 

The two 8 ohm jacks are intended for plugging in two 16ohm cabs (they'll be in parallel, so you'll wind up with the correct 8ohm load for those jacks)

 

I'd go with the 16 ohm speaker load into the 16ohm jack, naturally. That way, the load will match and the tubes will sound their best, and you'll most likely be using a full secondary winding on the OT; which, theoretically, should give the most detailed reproduction possible. Course, this is a guitar amp we're talking about, and theory often gets tossed right out the window.

 

Gil...

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The two 8 ohm jacks are intended for plugging in two 16ohm cabs (they'll be in parallel' date=' so you'll wind up with the correct 8ohm load for those jacks)

 

I'd go with the 16 ohm speaker load into the 16ohm jack, naturally. That way, the load will match and the tubes will sound their best, and you'll most likely be using a full secondary winding on the OT; which, theoretically, should give the most detailed reproduction possible. Course, this is a guitar amp we're talking about, and theory often gets tossed right out the window.

 

Gil...[/quote']

 

Thanks Gil, again!!!

 

I actually started using the 16ohm jack a couple days ago and found that it sounds better,

I believe the So Cal was designed to sound best with a 16ohm cab since that is the specs on Epi's matching cab for it.

 

I've always ran the Marshall in stereo with my past set-ups, so if I did run it again that way with the So Cal now it'd be the 2-4ohm speaker outs into the 2-8ohm jacks on the cab? This is what the So Cal manual says if you run out to 2 cabs. I thought 4ohm was better since it's less resistance and therefore more true tone(?) and sound comes out? IDK, maybe that's better for clean & loud more than crunchy and as loud as the So Cal is so I think the 16 ohm suits it better for that reason.

 

Speaking if which, I'm still not able to turn it up too much at home but I definately like the tone of the amp more now and with some kewl pedals I've added it really sounds good. I ordered a 12AT7 to try in the PI slot and a 12AU7 to try in the reverb slot. I also went back to the Ruby EL34B-STR's it came with as I think they sound a little better than the EH 34's and Miles (ex-Groove Tubes and guitaramplifierblueprinting.com) gave the Ruby's a great review and that guy's tough, LOL!!!

 

I am gonna try and bring it to a friends rehersal room in the next couple weeks where I can really open it up without making my neighbors deaf and see what this bad boy can do, I'll keep you all (that give a crap) posted.

 

Jesus of Suburbia

"Friend of many, savior to none"

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Yes, and thomann.de told me May 8th so it might not be that far off. Hopefully it's true. They'd probably get here to Europe before the US if they're being shipped from China anyway. :-/

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Two 4ohm speaker loads in parallel would give you a 2ohm load. VERY BAD for the amp.

 

Maybe you should take a look at this.

http://www.abrown.com/pics/wiring.gif

 

Gil...

 

Yeah' date=' I thought the same thing Gil, but here's what the So Cal owners manual says which confused me:

 

"The Parallel Speaker jacks allow the player to use the So Cal 50 head with various speaker cabinets. Always match the impedance of the individual speaker cabinet to the same impedance of the output speaker jack. [i']When using two speaker cabinets with the same impedance rating be sure to calculate the total impedance load. Example: Two 16 ohm speaker cabinets shoulde be plugged into 8 ohm speaker jacks. Two 8 ohm speaker cabinets should be plugged into 4 ohm jacks.[/i] Do not use two speaker cabinets with differant impedance rating. Always use a high quality speaker cable. Never turn on the amp unless the speaker cable is connected from the amp to the cabinet."

 

Now using that logic, I'm counting the Marshall 1960A cab (I love that cab) as two 2-12" cabinets when used in the stereo setting, 8 ohms each side, and this is how I ran the same cab with my old Peavey Classic 60/60 power amp using its 8 ohm outs with no issues ever. I always thought you matched ohm to ohm, period. Like I said I ran the amp already using the 2-8ohm jack outs in stereo with no probs but I think I prefer the 1-16ohm out and is probably how the amp should be run. Just wanted to show you what the manual said because I don't think I've ever seen that in an amp manual before.

 

JoS

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The manual is correct and saying the same thing I've been trying to say.

 

Simply put, just add up your total speaker load to the amp, and use the jack that matches the load. If the load on a jack is half, the reflected impedance (load) on the power tube(s) will be half. If the load on a jack is double, the load on the power tube will be double. So always use the jack that matches the load.

 

Tubes operate best under a given load. If you change that load by plugging your speaker into the wrong jack, you change the operating characteristics of the tube. It can run hot, or cold, and either way the tone generally isn't optimal. Also, the tube's life span will be shorter, and in a worst case scenario you can damage the iron and/or the amp.

 

I'll say it again. Always use the jack that matches the load.

 

Unless you know the ins and outs of amps, AND the iron you're working with and what it's capable of, AND the tubes you're working with and their specs and limitations, you're begging for trouble if you don't follow the manufacturers recommendations.

 

So, one more time, with feelin'... Always use the jack that matches the load!

 

Gil...

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So why did they even put 2 4-Ohm outs on the amp if it's not good to use them both and the amp is not recommended to be used with 2 differant rated cabinets?

 

I might still be being a dufus but according to the chart if I ran it with 2 16-Ohm cabs then it'd be the 2 8-Ohm slots so 2 8-Ohm cabs (stereo setting on my cab) would be the 2 4-Ohm outs? Like I said, I used the 2 8-Ohm outs into my cab's stereo 8-Ohm jacks with no prob when I first got the So Cal as I also used to with my old Cyber Twin head in stereo which was the proper matching for that amp.

 

Actually it's a mute point now because I'm only going to use the 16-Ohm out to my Marshall set on mono uing the 16-Ohm jack (I have the option of using 4-Ohm or 16-Ohm in mono) since this is a mono amp and it sounds better to my ears anyway, but I just wondered why they made 2 4-Ohm outs on the So Cal if it's not 'healthy' for it?

 

Sorry if I'm continuing to be ignorant about this issue Gil, my Mom always said I was 'hard-headed', LOL

 

peace & tone,

JoS

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By july it'll be down to 14 watts.

 

and made by siberian huskys.

 

TWANG

i'd rather have it that way.

 

dog labor produces a higher quality product than sweatshop labor. they're eager to please.

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So why did they even put 2 4-Ohm outs on the amp if it's not good to use them both and the amp is not recommended to be used with 2 differant rated cabinets?

 

I might still be being a dufus but according to the chart if I ran it with 2 16-Ohm cabs then it'd be the 2 8-Ohm slots so 2 8-Ohm cabs (stereo setting on my cab) would be the 2 4-Ohm outs? Like I said' date=' I used the 2 8-Ohm outs into my cab's stereo 8-Ohm jacks with no prob when I first got the So Cal as I also used to with my old Cyber Twin head in stereo which was the proper matching for that amp.

 

Actually it's a mute point now because I'm only going to use the 16-Ohm out to my Marshall set on mono uing the 16-Ohm jack (I have the option of using 4-Ohm or 16-Ohm in mono) since this is a mono amp and it sounds better to my ears anyway, but I just wondered why they made 2 4-Ohm outs on the So Cal if it's not 'healthy' for it?

 

Sorry if I'm continuing to be ignorant about this issue Gil, my Mom always said I was 'hard-headed', LOL

 

peace & tone,

JoS[/quote']

i thought it was "moot" not "mute"

...

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I need the VSr. So bad.

When I got the VJr, it changed how I played. I loved the control I had over my sound. I know that sounds weird for an amp with one knob, but it made me use the knobs on my guitars, which I always knew mattered, but didn't bother with. Now, I want to replace my 30w tube with the VSr, even just to compliment the VJr.

As long as the 6V6's sound like I imagine they will, the VSr will have a place in my heart.

Plus reverb? If it is spring I'll **** my pants and never leave my gear room again. If it isn't, maybe a tank can be added.

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...When I got the VJr' date=' it changed how I played. I loved the control I had over my sound. I know that sounds weird for an amp with one knob, but it made me use the knobs on my guitars, which I always knew mattered, but didn't bother with...[/quote']

 

I know just what you mean. I have 3 small tube amps including my V3 VJ and it really helped me become better with my playing as it's hard to hide mistakes and with 1 knob I started using my guitars knobs more.

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I know just what you mean. I have 3 small tube amps including my V3 VJ and it really helped me become better with my playing as it's hard to hide mistakes and with 1 knob I started using my guitars knobs more.

 

It has made me such a better player. Before I got it, I sold my entire pedalboard, and just started form scratch. Living in an apartment, the Vjr made me understand the dynamics of guitar so much better.

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I know just what you mean. I have 3 small tube amps including my V3 VJ and it really helped me become better with my playing as it's hard to hide mistakes and with 1 knob I started using my guitars knobs more.

 

+1 on that. I had the same experience when I built my ax84, which is a 5 wattish 6v6/el84/el34 class A amp, very much like the VJr.

 

I am very eager to get the VSr, and I too wonder about what kind of reverb it'll have. Since it has 4 12ax7's it will at least be possible to add tube-driven spring reverb through some modding, perhaps at the sacrifice of gain depending on what they're used for.

 

I'm quite convinced I'll be recieving the VSr in mid-May having pre-ordered it from 3 different places stating May 8th-17th as ETA, and I'll be sure to put up a review here a soon as I get it!

 

 

btw, have any of you here had any luck at getting schematics for the VJr or other epi amp?

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I am very eager to get the VSr' date=' and I too wonder about what kind of reverb it'll have. Since it has 4 12ax7's it will at least be possible to add tube-driven spring reverb through some modding, perhaps at the sacrifice of gain depending on what they're used for.

[/quote']

if there's really no "tube tone" without distortion, why bother? just leave it...

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if there's really no "tube tone" without distortion' date=' why bother? just leave it...[/quote']

 

of course there is, I find tube amps are much more dynamic, and they break up a lot more smoothly. And of course the added warmth of slight soft clipping.

 

and yes I would bother. If it ain't broke, mod it. hehe.

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