preamp tubes 12ax7 vs. 12at7

[brads]

[B]

Originally Posted by sjhusting

watch what you ask for i have friends in Mankato and a sister in St. Paul ... ever hear of City Mouse? Or the Castaways?

steven

I was the singer/guitarist in City Mouse in 1979.

[sjhusting]

No *****? Then you know my brother, Footie?

[scoots]

sjhusting, i was unable to download message. new to tube amps, new to computers. out her in the country, we got indoor plummin' just last.... also posted a question on JohnnyCrash's thread "how's the verb..." thread. any thoughts?

[scoots]

sorry sjhusting, message was from another guy, still any thoughts on the speaker question?

[JohnnyCrash]

Originally Posted by scoots

sorry sjhusting, message was from another guy, still any thoughts on the speaker question?

What speaker question?

[JohnnyCrash]

Oh sorry, this one:

Originally Posted by scoots

JohnnyCrash, you still out there? got a question on speakers. through the hrdeville 212, i run a boss me-50, a multi-effects stomp box. this has a compressor on it and a noise gate, so it's kinda cool for clean sounds. i also like to take this out and run right off the amp. question--- i'm mostly into the clean sound, but i also use distortion as well. the me-50 has a seperate bass and treble on the distortion/overdrive "section". to turn up the bass on it to get a decent sound, once you turn the volume up, it sounds like you're going vibrate the speakers out of the cabinet. you can let it rip clean and sounds good. do you know of speakers that i could put in here to get the best of both worlds, or is this an either/or?

1. When you use the amp's overdrive without the BOSS does it still make a rattling sound?

2. When you "let it rip" clean - how loud are we talking? At least as loud as when overdriven?

Generally, speakers can be fine for both clean and dirty. There's not really a compromise in tone either way USUALLY. Some speakers don't excel at some things obviously.

When you have low power rated speakers in an amp driven loudly, speaker breakup enters the equation... it sounds like when you play clean and loud the speakers don't breakup, so power handling/breakup probably isn't the issue (the Fender design are probably rated highly for power to avoid blowing).

My initial guesses would be:
1. The BOSS is pumping a ton of bass into the amp and the speakers are vibrating.
2. The BOSS is making the noise, seperately from causing it in the speaker.
3. At high volumes the speakers are rattling because they may be mounted a little loosely.

Its hard to say though, given that I'm not sure what exactly you're describing. Do my first two questions make any sense? If it doesn't rattle when using the amp's drive, and it doesn't rattle when played clean very loudly - its gotta be something with the BOSS.

PS
My old guitar player uses a Pro Tube series "New" Twin with the BOSS ME-50, he had some good sounds goin' on... and I'm extremely biased against effects. I bet you can dial in some tastey sounds with your setup!

[brads]

Originally Posted by sjhusting

No *****? Then you know my brother, Footie?

Yes, I remember Footie. Great guy. Didn't he wind up in Nashville, or was it Milwaukee?

[scoots]

JohnnyCrash- yeah, it's the boss pedal adding all that extra low end in. do you know of another speaker (brand, name) that you could recommend that could handle the extra low and still sound good clean, or is that kind of where you're trading one benefit for another?

[scoots]

i'm just kind of in experimental mode. i want to see what i can do with this amp, what i can't...playing around.

[scoots]

i want to know what i like, i want to know what i don't like

[sjhusting]

Originally Posted by brads

Yes, I remember Footie. Great guy. Didn't he wind up in Nashville, or was it Milwaukee?

Milwaukee. He was up for the Hall of Fame ceremony in May, had a great time jamming with Ronnie and the rest.

[JohnnyCrash]

Originally Posted by scoots

JohnnyCrash- yeah, it's the boss pedal adding all that extra low end in. do you know of another speaker (brand, name) that you could recommend that could handle the extra low and still sound good clean, or is that kind of where you're trading one benefit for another?

Nah, you wouldn't be trading anything off. Different speakers do color the sound differently. For instance a Celestion Vintage 30 has this big midrange "bump" that some folks love for hard rock, whereas other folks think it sounds too "honky" like a goose honk. So it all comes down to taste.

Hmm...

You know, there are just so many speakers its hard to recommend something.

I've been on a neodymium kick lately... but either way, I would stick with speakers that are rated for a lot of power (at least 45 watts each for a total of 90 watt handling).

You may want to read up on some of Eminence's "Patriot" line (based on classic American styled speakers - their "Red Coat" line is based on British speaker sounds). Eminence seems to be a favorite here on TDPRI for a lot of folks.

According to Eminence, the "Red White & Blues," "Screamin Eagle," and "Black Powder" boast tight bass without seeming to warm the highs too much. If you want warmer or more mellowed highs (less bright) you can try other speakers.

I have all kinds of amps, so I usually match them with speakers for a certain flavor. If I want an old '50s kind of creamy top end, I use AlNiCo speakers (I like Jensen reissues, but many here prefer Webers). If I'm looking for a '60s-'70s Classic Rock sound, I usually go to a Celestion speaker.

It really depends on:
1. The kind of music you play.
2. What specifically you want the speaker to "help" the amp with (in your case, tightening up the bass).
3. Your taste.

I'd suggest starting a new thread in the "Amp Central Station" forum here again. This time asking about speakers that'll tighten up the bass - be sure to mention the amp and guitars (pickups too) you're using, the kind of music you play, and be very detailed and specific when describing your tastes and issues with the low end...

You may get a ton of different answers due to varied tastes, but it still may help narrow down your search if someone has similar tastes to yours.

I'd also suggest reading as much as you can too - this stuff is fascinating and addicting though!!

[scoots]

appreciate it JohnnyCrash, this is definately my favorite new addiction! between the amp and the me-50, so many knobs, so little time...

[RomanS]

scoots,
if you are looking for a speaker that can handle LOTS of bass, stays clean very long before breaking up, and sounds very punchy & transparent, without being too harsh on the high end, try the Eminence Legend 121 (even better, this is one of their lowest priced speakers).
The L121 can even handle the TONS of bass from my JTM45-clone...

[scoots]

appreciate the info RomanS, i'll look into them!

[Silverface]

I'm going to go back to the start:

"The Master Volume completely eliminates any need to fool with different gain preamp tubes.'

This an incorrect statement, and reading the rest of the posts, I'd be wary of the "harshness" with this type of information as a basis of into into the thread. I cannot imagine someone making that statement and then dissing another website for technical innacuracies.

The MV has nothing to do with the gain level of various tubes - and the mu is not the ONLY effect of those tubes - there are different tonalities afoot as well.

Changing the gain of those tubes changes the bias of the preamp circuit - this affects mids, highs, bass, attack, decay and just about every other variable. Saying the MV eliminates the reason to try different gain-level preamp tubes shows a complete lack of understanding of all the OTHER tube functions, and the interactive parts of the circuit. Or, maybe the poster just doesn't care.

Now to answer some questions with some actual information:

The 12AT7 iss normally not considered an audio tube. It's used in parts of the reverb or tremolo circuits but not as a primary preamp tube. It tends to be very harsh sounding, with nasally mids and little low end. It makes a great pkhase inverter in circuits designed for it - but you don't use one in the V1 or V2 hole.

The 5751 is a medium gain tube. Normally good for taming headroom problems with Fenders when used in V2 (for the reverb channel). Wll sound weak in an amp with cascading gain stages (Mesa, Soldano, etc.). But in a Fender,it's probably my favorite preamp tube to clean things up.

Even lower gain versions are the 12AY7 and 12AU7. Most of the tweeds used a 12AY7, and it's worth trying if you are attempting to clean up your sound. The 12AU7 works very well in some applications and shouldn't be quickly discounted.

But - before doing ANY of this, make sure you have fresh filter caps, good power tubes and know how to adjust the bias. As you switch out preamp tubes you'll want to alter some bias settings to compensate a bit - it will give you a much better feel of the amp's capabilities.

Of course, make sure you know the safety precautions before opening up the chassis - if you don't DO NOT do it - take it to a tech.

Speaker would be last on my list. you can spend hundreds of dollars chasing speakers when simple tube subsitution could have been your solution.

Ignore overdrives completely until you've found YOUR clean tone at a usable volume - THEN try overdrives. Overdrives work best with a hard-driving amp. Otherwise, you're looking for a distortion pedal, a different animal.

Ignore the tube glow Uless it's bright red and in the middle of the side of the tube - then a plate is runnning away, so shut it off and have it serviced. Normal tube glow is from the filaments,and varies quite a bit.

Again - make sure the amp is properly serviced before you dig into changes. And do LOTS of reading.

Good luck.

[scoots]

what "v" position were ya thinking of with a 12ay7, v1?

[Silverface]

V1. that's the preamp tube. V2 is only for the "drive" channel...which hopefully you're not using.

[sjhusting]

Not quite, both channels go through V2a - drive channel only goes through v2b. Master volume is on drive channel only.

steven

[Silverface]

A slight omission in wording - still the same tube you should replace to test alternates, as V1 is dedicated to that channel. If you replace V2, you can't exactly get a 12AY7 in one half and a 12AX7 in the other, at least in commonly found tubes. The drive channel also has zero to do with V1.

While 1/2 of V2 does affect the normal channel, it's V1 that's going to give you the greatest changes. The part of V2 that affects the normal channel is primarily a "make-up" preamp due to gain lost in the tone stack...it doesn't set the overall direction of the amp. You want to try variables in the *first* tube you guitar (or effects) sees. THEN you can fool with the second one, where you can "massage" the tone.

Sorry to have to explain the obvious, but given some of what I've seen posted lately I guess I need to go to fully expanded and verbose answers most threads to avoid being corrected about irrelevant infomation.