Sorry it won't let me post a pic
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- Thread starter Iceman63
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It influences everything. And when I've experimented with swapping it on my Boogie, only the stock tube sounded right. It had a profound impact, to my ears. I say give it a try with a variety of options...12at7, 12au7, etc.
Here's my thinking about PI tubes, though to an extent this applies to a lesser degree with other preamp tubes:
Every brand and model of preamp tube has a different nominal gain level, and each individual tube also measures and overloads slightly differently. As an example, the JJECC83s that PRS uses in its preamps is a substantially hotter tube than most 12AX7s. I find that substituting a less hot tube in the PI spot in my DG30 really alters the tone of my amp, and not necessarily in a way that I prefer, or that it was designed to have.
An NOS 12AX7 in the same position that sounds absolutely fantastic in V1 or V3 of the same amp sounds a lot less good in the PI position, V4.
In my experience, the PI tube has less of an effect on the tone of the amp than other preamp tubes, but has a very noticeable effect on the level of the signal sent to the output stage. And of course, the level of that signal affects the overall sound of the amp because it's what drives the output tubes into doing their thing.
In the case of a Mesa, the output stage is expecting a certain level from that preamp, and since the power tubes aren't adjustable, it may make even more of a difference than usual with other amps. I think that may be why the particular PI tube is even more critical with a Mesa amp.
I always preferred Mesa tubes with my Mesa amps as well.
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mulehead
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New 2 Channel 'C' owner here - So to your point about NOS 12AX7's...where would you source those from? I've looked at the tube store and tube depot, and there are several to choose from.
I deal with The Tube Store, Tube Depot, KCA NOS Tubes, and a small shop in Canada where I found my NOS BRIMARs (drawing a blank on the name at the moment).
One thing -- if your amp sounds great with the stock tubes, leave 'em in there. I only roll tubes when something needs replacing, or when I want to change an attribute of an amp for a particular reason.
mulehead
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Unfortunately, I heard a 'pop' when i last turned it on and it seemed muddy to me on the red channel - Blue sounds good, so i'm hoping that just changing out the 3 12ax7's will do the trick.
I hope so!
Iceman63
New Member
Thanks for all the info guys. rolue, I do'nt have that sticker in mine that I've seen, but I'll take a better look. Like I said, will all JJ's, the amp seemed a bit dull to me. I wanted a little more chime on the red channel. Changing out V1 and V2 definately made a difference. But again, too open(for me). Maybe it was the Penta....I have only so many spares laying around. I'm not usualy one to do much tube rolling if I can help it. Right now I'm back to all stock tubes, but with an old RCA 7025 in V1, and I think I like it. I've got a Sovtek 5751 that I may try in the PI. But like LSchefman was saying, it may not effect the tone much. I'll probably leave it alone.
One thing I have done is dial the bass on the red channel way back to around 9 o'clock, as well as not using the pull depth. I like low end thunk, but I think it can be overdone. Dialing back on the bottom end takes that flub out and brings out more mids and highs. Even running the bass at noon was a bit too much for me. So it seems we're alway learning huh?
One thing I have done is dial the bass on the red channel way back to around 9 o'clock, as well as not using the pull depth. I like low end thunk, but I think it can be overdone. Dialing back on the bottom end takes that flub out and brings out more mids and highs. Even running the bass at noon was a bit too much for me. So it seems we're alway learning huh?
Always learning! After the last post the other day one of the preamp tubes in my HXDA went noisy as hell, and since I shot my spare tube wad on the DG30, I had to order a few from The Tube Store. So I'll do a little tube rolling and see what sounds good in there - wouldn't be surprised if it was the stock tubes but I'll try a few. I do have one more BRIMAR left, but I want to be able to swap it with a good JJ, so I can compare good to good.
Hollis Prince
New Member
I really don't understand putting a boost pedal in a loop at all.
That would come toward the end of the circuit, after the V1, and after the EQ, the two things that a boost pedal most affects, and in the case of the EQ, the tone shaper for the boosted signal.
I mean, sure you're gonna hear it, and I suppose there are no rules, and if it works it works, but...
Sorry, for me, does not compute.
I use a boost both in front and in the loop. I use a TS-9 to boost the front of the amp and an MXR 10-band EQ in the loop as a solo boost. The EQ pedal just simply makes it louder; it doesn't change the tone at all(I have the EQ set completely flat). In retrospect, I wish I would've gotten a specific clean boost instead of the EQ pedal, but at the time I thought the EQ might come in handy for tone shaping. It turns out that I love my Electra Dyne just the way it is. Any EQ-ing just detracts from the tone.
Anyways, hope this helps see how some folks use a boost in the loop.
Interesting!
I'm one of those "control the amp with the guitar volume" guys, so I just set the amp up for a crunch tone with the guitar volume around 5-6. Roll it up for more gain, down for less.
Of course, that doesn't solve the boost problem, so I use a clean boost by Suhr to give myself another option. But I run it in front of the amp. Heck, we're all different, and I can't argue with someone's choice that really works for them! Seems I've mellowed out a little about this...
Iceman63
New Member
You guys with PRS combos, namely the H or C 50, what speakers are they loaded with? Mine has a Celestion 70/80 in it. I've done a little research and it appears that this is not on average a highly regarded speaker; though, some like it.
I have two 1x12 cabs; a Suhr w/a WGS Veteran 30, and an Avatar semi open w/a G12H30. I'm going to try these out. I also have a brand new WGS ET-65 still in box that I was debating on selling. But may try it in one of the cabs.
Actually, if I keep this Custom 50, I'd really like to have it put in a headshell. It's just too heavy for me as a combo with my hair trigger lower back. Anyone happen to know a builder, or how best(affordable) to do this?
Also, where are you guys running your loop volumes? I'm not using the loop currently. Just wondering how it effects the output section tonaly.
I have two 1x12 cabs; a Suhr w/a WGS Veteran 30, and an Avatar semi open w/a G12H30. I'm going to try these out. I also have a brand new WGS ET-65 still in box that I was debating on selling. But may try it in one of the cabs.
Actually, if I keep this Custom 50, I'd really like to have it put in a headshell. It's just too heavy for me as a combo with my hair trigger lower back. Anyone happen to know a builder, or how best(affordable) to do this?
Also, where are you guys running your loop volumes? I'm not using the loop currently. Just wondering how it effects the output section tonaly.
