stupidest question ever. tube mic pre as guitar amp

[wsaraceni]

I've always LOVED the beatles "revolution" guitar tone, and everyone says that you can't get that tone because it's the guitar plugged directly into the board and overdriven. so technically speaking why couldn't you just build that tube mic pre as the preamp of a guitar? i was thinking you could build that, the output of it could go to an effects send. in the same chassis build an effects return and a cleanish power amp. maybe something with 6l6s or 5881s or something. worst case, move it to it's own chassis and you have a nice tube preamp for recording, and you can just build a guitar preamp in it's place.

[Milkmansound]

http://www.dripelectronics.com/index.ph ... &Itemid=33

these sound awesome - I have a friend who built 4 of them

maybe you can use one as the front end of an amp - but its going to be really expensive with those input and output transformers and you certainly don't want to delete them. Mic preamps are even more colored by transformers than guitar amps are in my opinion

[Reeltarded]

Before you waste all this time, go plug your guitar into a PA console direct and see if it makes you really happy.

I predict not.

[wsaraceni]

it really wouldn't be a waste of time. as worst case scenario would be you just building a killer $500 tube mic preamp. but after reading more. i do agree it probably won't work well into a guitar amp

[Reeltarded]

No, I am saying you won't get what you hear on those recordings by playing a mic amp into a power amp.

Worthy project if you need a mic amp. I have to build 16 of those very mic amps, plus a summing mixer... I have heard.

[renshen1957]

No, I am saying you won't get what you hear on those recordings by playing a mic amp into a power amp.

Worthy project if you need a mic amp. I have to build 16 of those very mic amps, plus a summing mixer... I have heard.

Hi,

The Beatles experiment with DI.

The Beatles Revolution single distortion was a result of over driving a (tube) mixing console by routing the signal through two microphone preamplifiers in series while Emerick (the engineer) kept the amount of overload just below the point of overheating the console between the guitar and desk, plus throw in some mismatched impedance, and/or unbalanced/balanced connections.

So you will have to build two tube microphone preampliers to capture the tone. Now what tube was used in the mixing console? EF86 pentodes or EF86 wired as a triode? 12AU7? You've got a bit of research, the Beatles gear is well documented so it isn't impossible.

Don't bother with the PA, you wouldn't like the sound through a PA as this would not approximate or capture the sound you are after. Todays PAs are transistor/IC circuits instead of Valve/Tube of 50 years ago.

Realtarded makes a good point in his posts, plus you don't know what other studio "trickery" was involved to capture the sound originally.

Good Luck

Best Regards,

Steve

[tubeswell]

Tube mic pres are designed to work with the output impedance of mics in order to reproduce vocals with minimal distortion. If you want an approximate idea of what a guitar sound likes into a tube mic pre, plug your guitar into the lo-gain input of your basic fender amp.

[Reeltarded]

plus you don't know what other studio "trickery" was involved to capture the sound originally.

Good Luck

Best Regards,

Steve

If you want to approximate that sound, it can easily be done with a $100 mic amp pair, no tubes required. Even some distortion units.. clean boost pedals make that sound, but even closer to the finished sound than looping mic amps. Umm.. what's the one.. grey.. Fulltone thing.

MY favorite direct sound is Black Dog, which uses a Urei 1176 as a line amp.

[tictac]

You could experiment with the REDD circuit and build a preamp just for guitar but use the REDD 47 circuit. I think and E88CC is a 6DJ8 but I think you could get away with using a 12AU7 instead.

Skip the input and output transformers and cascade two REDD preamp circuits; you could even use a less expensive output transformer on either preamp output and have a very cool DI box for guitar.

You don't need the expensive transformers and the regulated power supply if you're just going for a distorted guitar tone.

All you need is a little PT, four tube sockets, four tubes, some resistors, capacitors, and hardware...

just a thought,

TT

[Structo]

I picked one of these up to help a SM-57 mic for guitar recording.

Not sure how much output it is capable of but these things are only about $30.

[img:290:290]http://static.musiciansfriend.com/deriv ... 180581.jpg[/img]

http://www.musiciansfriend.com/pro-audi ... mic-preamp

[Milkmansound]

when you open that thing up look to see if its a tube giving you the preamp gain, or an opamp

[tubeswell]

Seems cheap enough. They must of spent a lot of time hand-selecting the chinese 12AX7

[Structo]

I did open it to put in a nice black plate 12ax7 but I really didn't look it over too carefully.
It does have a pcb so you could be right.
I didn't want to mess around too much with it as it has two ribbon cables between the two pieces of chassis.

For $30 I think it works well.

But I think more likely it uses JFETs which are more tube like.

You know it's funny that we have become tube snobs but most of us won't hesitate hooking up a solid state effects pedal or digital box to enhance our tone.

[Milkmansound]

hate to say it, but there is a reason a lot of high end audio gear is made with Mosfets or Jfets... couple them with a proper input transformer, and you get a really detailed and harmonically rich sound. The best recording gear in the world does not have tubes in it - Neve, API, SSL... the list goes on. Tubes are too finicky and hot for modern recording studios. Sad but true. That said, every studio I have ever been in has at least 2 LA2As

power amps kind of have their own special thing going on that is really enhanced by tubes - but mic amps and effects don't really need that "thing".

If you want to see what I am talking about - I recommend building a Hamptone JFET mic preamp for yourself. It sounds gorgeous even as a DI and has a proper marraige of JFET and transformer:

http://www.hamptone.com/micpres.html

his tube and JFET mic preamp feature the *exact* same circuit if you look at them closely.

anyway, what were we talking about? The Beatles? Sorry for the side-track

[Reeltarded]

I have to use a tube mic pre on ribbon mics!