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#1
Posted to rec.audio.tubes
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Building my own preamp
I want to build a dual mic preamp, but I'm not really sure where to
start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. It needs to have phantom power, and be able to take balanced inputs and outputs. If possible I'd also like to be able to flip a switch and turn it from a mic pre to a guitar pre (with distortion), but if not that's just fine. Are there any books or schematics on the net you'd recommend? |
#2
Posted to rec.audio.tubes
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Building my own preamp
"gjsmo" I want to build a dual mic preamp, but I'm not really sure where to start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. It needs to have phantom power, and be able to take balanced inputs and outputs. If possible I'd also like to be able to flip a switch and turn it from a mic pre to a guitar pre (with distortion), but if not that's just fine. Are there any books or schematics on the net you'd recommend? ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ...... Phil |
#3
Posted to rec.audio.tubes
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Building my own preamp
** Do you own Google search - *this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... *Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. |
#4
Posted to rec.audio.tubes
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Building my own preamp
"gjsmo" ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html What'd you search? ** Would you believe " tube mic preamp " ???? Google the through up several options, the third of which added the word " schematic" and the forth added the term DIY. I clicked on the third one. I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. ** All those transformers will cost you though. ...... Phil |
#5
Posted to rec.audio.tubes
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Building my own preamp
On Oct 21, 7:14*pm, gjsmo wrote:
** Do you own Google search - *this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... *Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. Any of the xfmr vendors will give you schematics for several circuits to use with their products, or you can copy a desireable vintage unit. Or start from first principles on your own. It's up to you. Copying a popular vintage unit is the fastest and direct path to likely success, provided the transformers you can get are compatible. For a guitar pre, copy the front end of a guitar amp you like up to the drivers and have it drive a line output xfmr. Mesa MkIIB, Marshall plexi and Fat Howard circuits are most popular. |
#6
Posted to rec.audio.tubes
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Building my own preamp
Bret L wrote:
On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian |
#7
Posted to rec.audio.tubes
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Building my own preamp
Ian Bell schrieb:
Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian ....Ian, with all due respect, but those boxes are intended for the use as a DI. More or less transparent with a tube touch, but NOT "distortion". A guit preamp (think mesa, marshall, VHT) is intended to change the signal completely in a certain way. A mic-preamp with a Hi-Z input does NOT. kindest regards Jochen |
#8
Posted to rec.audio.tubes
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Building my own preamp
On Oct 22, 1:18*pm, Ian Bell wrote:
Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - *this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... *Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. *Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Yes, but it isn't really intended for lead guitar use. It works okay for acoustic guitars and particularly bass though usually a DI box works better in a lot of cases. Recording a guitar direct to "tape" (it's usually PT) gives a sound not too unlike Les Paul-not a regular Les Paul guitar through an amp, but the sound Les Paul actually has on his records from the 40s and 50s. No one really wants that sound today, or really ever.(That, plus their weight, made the only Les Pauls Gibson ever made resembling what Les actually used unsaleable.) It sounds like a steel guitar without the bends and glisses. What is popular are several types of amp simulators and virtual amps. These range from the old Tom Scholz Rockman to DSP implementations in software through PC cards, to running guitar amps into complex speaker emulators or sealed speaker boxes. Acoustic guitars have several types of pickups or internal mics. Internal mics are handled like any other mic. Piezo pickups are generally buffered and treated as a line signal. So yes, by all means put a Hi-Z input on your mic pre. But that's nothing much to do with an electric guitar. A guitar pre, by contrast,, is usually used in front of a power amp in a rack setup. These underrated little beasts allow power amps otherwise not of much use-old PA amps, as well as hi-fi amps, and pro sound power amps to be used for guitar. If one is after clean jazz and country sound, any fairly clean power amp works. A lot of dinky mono alleged hi-fi amps as well as SET's borrowed from someone's slobber-fi setup at home will give the recording guitarist a fantastic palette of cool distorto sounds this way too. Recording with the guitar pre is possible but not that much done. |
#9
Posted to rec.audio.tubes
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Building my own preamp
jh wrote:
Ian Bell schrieb: Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian ...Ian, with all due respect, but those boxes are intended for the use as a DI. More or less transparent with a tube touch, but NOT "distortion". A guit preamp (think mesa, marshall, VHT) is intended to change the signal completely in a certain way. A mic-preamp with a Hi-Z input does NOT. kindest regards Jochen |
#10
Posted to rec.audio.tubes
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Building my own preamp
jh wrote:
Ian Bell schrieb: Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian ...Ian, with all due respect, but those boxes are intended for the use as a DI. More or less transparent with a tube touch, but NOT "distortion". A guit preamp (think mesa, marshall, VHT) is intended to change the signal completely in a certain way. A mic-preamp with a Hi-Z input does NOT. kindest regards Jochen Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. A clean signal is required for recording, not a distorted one. Cheers Ian |
#11
Posted to rec.audio.tubes
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Building my own preamp
Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. *A clean signal is required for recording, not a distorted one. There are several issues in doing this, one being that the crest factor of a live guitar feed can be very high indeed, and that therefore a surprising dynamic range is needed even for a typical track where the dynamic range seems small. This is also why guitar drivers are very tough as opposed to normal modern hi fi speakers. Yes, it can be done, but it doesn't work as well as you'd think. It's generally better to record electric guitar "wet", in a form similar to what is in the end required. You can EQ or compress after that but the flexibility is indeed limited unless you do want a deliberately processed sound. Acoustic backing tracks, again, are a whole different proposition, especially if "that demo sound" is what you indeed want. That sure enough is how you get it: plug an Ovation straight in to a mic pre's straight hi Z in. If you use silk and steel strings you've got it nailed. One refinement I don't see often enough, is recording an electric guitar in stereo, with one clean and one raunchy signal through two amps mic'd. You can then submix them or stereo pan them. To keep buzz down the studio has to be really quiet unless you put the amp heads together and bond them carefully, lifting the AC ground, and use long speaker cables. I've advocated wiring guitars stereo with two completely galvanically isolated channels but no one is going to listen to little old ground loop hating me on this one. Keith Richards diid this with the Stones a little bit but they never really took full advantage of it, he's always out there on one side in thr finished mix. |
#12
Posted to rec.audio.tubes
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Building my own preamp
Ian Bell schrieb:
jh wrote: Ian Bell schrieb: Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian ...Ian, with all due respect, but those boxes are intended for the use as a DI. More or less transparent with a tube touch, but NOT "distortion". A guit preamp (think mesa, marshall, VHT) is intended to change the signal completely in a certain way. A mic-preamp with a Hi-Z input does NOT. kindest regards Jochen Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. A clean signal is required for recording, not a distorted one. Cheers Ian :-O I thought he explicitely mentioned it, didn't he? Jochen |
#13
Posted to rec.audio.tubes
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Building my own preamp
Bret L wrote:
Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. A clean signal is required for recording, not a distorted one. There are several issues in doing this, one being that the crest factor of a live guitar feed can be very high indeed, and that therefore a surprising dynamic range is needed even for a typical track where the dynamic range seems small. This is also why guitar drivers are very tough as opposed to normal modern hi fi speakers. Yes, it can be done, but it doesn't work as well as you'd think. It's generally better to record electric guitar "wet", in a form similar to what is in the end required. You can EQ or compress after that but the flexibility is indeed limited unless you do want a deliberately processed sound. Actually, it does work rather well. I do it all the time and so do many pro studios. As I mentioned before, the point of doing it is to get a clean recorded sound which leaves your options wide open for processing. One option, which I am sure you have heard of, is re-amping where the recorded clean signal is played back through a guitar amp and miced up in the usual fashion. Cheers Ian |
#14
Posted to rec.audio.tubes
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Building my own preamp
jh wrote:
Ian Bell schrieb: jh wrote: Ian Bell schrieb: Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Cheers Ian ...Ian, with all due respect, but those boxes are intended for the use as a DI. More or less transparent with a tube touch, but NOT "distortion". A guit preamp (think mesa, marshall, VHT) is intended to change the signal completely in a certain way. A mic-preamp with a Hi-Z input does NOT. kindest regards Jochen Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. A clean signal is required for recording, not a distorted one. Cheers Ian :-O I thought he explicitely mentioned it, didn't he? Jochen Yes, you are right, I just checked back to his original post. I agree, if he want guitar amp like distortion he won't get it that way. Cheers Ian |
#15
Posted to rec.audio.tubes
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Building my own preamp
Bret L wrote:
On Oct 22, 1:18 pm, Ian Bell wrote: Bret L wrote: On Oct 21, 7:14 pm, gjsmo wrote: ** Do you own Google search - this was the very first hit. http://www.tangible-technology.com/tubes/1566/1566.html ..... Phil What'd you search? I never got that... or really anything close. I got stuff about either 1) really complicated stuff or 2) commercial stuff. Neither one interests me. That's pretty simple though. Having one unit double as a mic and (electric) guitar pre is a dumb idea. I guess that means there are a lot of dumb manufacturers out there then as pretty much every tube mic pre these days includes a high impedance instrument input. Yes, but it isn't really intended for lead guitar use. It works okay for acoustic guitars and particularly bass though usually a DI box works better in a lot of cases. Recording a guitar direct to "tape" (it's usually PT) gives a sound not too unlike Les Paul-not a regular Les Paul guitar through an amp, but the sound Les Paul actually has on his records from the 40s and 50s. No one really wants that sound today, or really ever.(That, plus their weight, made the only Les Pauls Gibson ever made resembling what Les actually used unsaleable.) It sounds like a steel guitar without the bends and glisses. Yes, but see my other post as to why you want to do this. Cheers Ian |
#16
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Building my own preamp
On Oct 23, 3:48*am, Ian Bell wrote:
Bret L wrote: Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. *A clean signal is required for recording, not a distorted one. *There are several issues in doing this, one being that the crest factor of a live guitar feed can be very high indeed, and that therefore a surprising dynamic range is needed even for a typical track where the dynamic range seems small. This is also why guitar drivers are very tough as opposed to normal modern hi fi speakers. *Yes, it can be done, but it doesn't work as well as you'd think. It's generally better to record electric guitar "wet", in a form similar to what is in the end required. You can EQ or compress after that *but the flexibility is indeed limited unless you do want a deliberately processed sound. Actually, it does work rather well. I do it *all the time and so do many pro studios. As I mentioned before, the point of doing it is to get a clean recorded sound which leaves your options wide open for processing. One option, which I am sure you have heard of, is re-amping where the recorded clean signal is played back through a guitar amp and miced up in the usual fashion. Yes, they even sell a box called ReAmp. it works but IMO not all that well. It's OK for jingles and demos but a good player needs to have something like the final live sound to work with, plus the original guitar feed ALWAYS has a lot of spikes you are going to lop off that are what make the speaker really crank. Tape or any real world digital system can't do it. I heard a dry line out recording of Brian May once that had all these "clickump" noises I had never heard before. Turns out May uses old, predecimal Brit coins for picks and that's the string against the pick. When he's through an amp you don't hear that, you just hear the string respond and the thump comes out in a whole different way. Reamp is GREAT for Halloween sound tracks though. ESPECIALLY if you have a Leslie and the old triangular Combo Pre that looks like something for a kirby vacuum. |
#17
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Building my own preamp
Alright, guys, I'll do my best to respond to this flood (not really
used to this kind of response time). @Bret L I agree with everyone else, it isn't a bad idea. It's just a new one to you (I think). Maybe having the distortion is a bad idea, but Hi-Z and Lo-Z isn't bad - what if I wanted to use a Hi-Z dynamic mic? Why is this a bad idea, to have one, instead of two seperate pre's, that I have to build, debug and maintain seperately? @Ian I've seen them, and from (supposedly) good manufacturers. @jh really? I made distortion once with a pretty good-sounding tube radio by using the phono output. Didn't sound too bad either, but it was very soft so needed to be mic'd. Of course, there was a pre-amp _before_ that, but nevertheless it's doing distortion with hi-fi equipment. @Bret L Fine then. But why can't I just turn the volume up on the pre and down on the mixer? If I give it enough gain, won't it distort? Isn't that what distortion is, pushing the tubes past their limits so they create a different sound? @Ian Yeah, I could do that... too bad I'm limited on recording channels. @Bret L Fine. And just how would you like me to record with the effects already in place? Oooh, I know! Why don't we let the preamp distort? (don't really want to be a jerk, but it's a solution) @jh Yeah, I did. But I also said it isn't required. @Ian No, I haven't heard of that. But that's a nice idea! Too bad I don't even have a good tube amp :-((((( Not much money, so the preamp's good enough. Fine. I won't do it. So should it have distortion or not? I'm torn between the ways. Or should I just go ahead and build separate pre's? Use one for mics and the other for guitars? My personal opinion is this: I need a mic pre, with preferably Lo-Z and Hi-Z inputs, and that's what I'm going to build. If I want to try distortion, I'm just going to crank up the volume until I hear something resembling what I want. Could I create a negative feedback loop for mics, and then put a switch somewhere to disconnect it (and allow distortion to occur)? Just a thought. |
#18
Posted to rec.audio.tubes
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Building my own preamp
I want to build a dual mic preamp, but I'm not really sure
where to start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. It needs to have phantom power, and be able to take balanced inputs and outputs. If possible I'd also like to be able to flip a switch and turn it from a mic pre to a guitar pre (with distortion), but if not that's just fine. Are there any books or schematics on the net you'd recommend? Balanced input and output means transformers, if you want simplicity. Phil's Altec link looks like a good bet. There's still a lot of work there for a beginner. Don't underestimate the work involved in metalwork and layout. A proper guitar preamp does proper guitar distortion, and a fair amount of filtering. Have a look at a Fender or Marshall for an idea of how the standard palette of sounds is achieved. You would need at least one extra 12AX7 and a lot of experiment and playing to produce the right sound, AFAICS. Something rarely discussed here. Exactly what does a guitar need to sound right, apart from a good guitarist? The common conception, flawed in my view, that fidelity can be reduced to the minimisation of distortion, is a license for musical and tonal illiteracy amongst audio engineers. As with all aspects of music and musical instruments, tradition is the best guide to development. It's a social thing: you can't just make it up on your own. No-one's mentioned books, and I can't think of anything suitable either. Depends what you already know, and whether you want to get into a hobby or just build one amp. Ian |
#19
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Building my own preamp
Bret L wrote:
On Oct 23, 3:48 am, Ian Bell wrote: Bret L wrote: Yes, what you say is true, however I do not recall the OP saying he wanted distortion. Presumably he wants a mic pre to be able to record and equally it is common to DI a guitar when tracking which allows the 'tone' to be determined later. A clean signal is required for recording, not a distorted one. There are several issues in doing this, one being that the crest factor of a live guitar feed can be very high indeed, and that therefore a surprising dynamic range is needed even for a typical track where the dynamic range seems small. This is also why guitar drivers are very tough as opposed to normal modern hi fi speakers. Yes, it can be done, but it doesn't work as well as you'd think. It's generally better to record electric guitar "wet", in a form similar to what is in the end required. You can EQ or compress after that but the flexibility is indeed limited unless you do want a deliberately processed sound. Actually, it does work rather well. I do it all the time and so do many pro studios. As I mentioned before, the point of doing it is to get a clean recorded sound which leaves your options wide open for processing. One option, which I am sure you have heard of, is re-amping where the recorded clean signal is played back through a guitar amp and miced up in the usual fashion. Yes, they even sell a box called ReAmp. it works but IMO not all that well. It's OK for jingles and demos but a good player needs to have something like the final live sound to work with, plus the original guitar feed ALWAYS has a lot of spikes you are going to lop off that are what make the speaker really crank. Tape or any real world digital system can't do it. Agreed. The point is they are different techniques with different pros and cons. Neither is the 'correct' way to do it, they are both equally valid. Cheers Ian |
#20
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Building my own preamp
"Ian Iveson" Something rarely discussed here. Exactly what does a guitar need to sound right, apart from a good guitarist? ** Ah - a guitar amp is just like a successful politician. In order to be liked, he must play to the prejudice of the voters. He must speak like the great politicians that have gone before him. Any pretence to novelty equates to political suicide. Tubes rule. SS is about as popular as communism. ..... Phil |
#21
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Building my own preamp
gjsmo schrieb:
Alright, guys, I'll do my best to respond to this flood (not really used to this kind of response time). @Bret L I agree with everyone else, it isn't a bad idea. It's just a new one to you (I think). Maybe having the distortion is a bad idea, but Hi-Z and Lo-Z isn't bad - what if I wanted to use a Hi-Z dynamic mic? Why is this a bad idea, to have one, instead of two seperate pre's, that I have to build, debug and maintain seperately? @Ian I've seen them, and from (supposedly) good manufacturers. @jh really? I made distortion once with a pretty good-sounding tube radio by using the phono output. Didn't sound too bad either, but it was very soft so needed to be mic'd. Of course, there was a pre-amp _before_ that, but nevertheless it's doing distortion with hi-fi equipment. @Bret L Fine then. But why can't I just turn the volume up on the pre and down on the mixer? If I give it enough gain, won't it distort? Isn't that what distortion is, pushing the tubes past their limits so they create a different sound? @Ian Yeah, I could do that... too bad I'm limited on recording channels. @Bret L Fine. And just how would you like me to record with the effects already in place? Oooh, I know! Why don't we let the preamp distort? (don't really want to be a jerk, but it's a solution) @jh Yeah, I did. But I also said it isn't required. There is not so much of a difference between an old tube radio and a generic guitar amplifier (think basic tweed fenders). I bet you did not get it to sound like a higain marshall or a rectifier without any external help - booster, overdrive or distortion. But a radio IS an amplifier and it has a speaker. Additionally the old speakers found in a radio have almost the same high end cut as the ones found in guitar amps. You're not talking about a preamp there anymore, it's more or less like a combo. Hi-Z inputs in tube preamps are a very nice thing to have, to go direct. I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap, unless you begin to shape the tone and add a decent speaker simulator - be it hardware or software. A decent quality microphone preamp and a serious guitar preamp are IMHO to completely different things. The first one normally tries to amplify the signal with the the most possible transparency, maybe add a tiny bit of distortion, whereas the other one shapes the signal, and creates lot of things, the initial signal did not have. As an special FX it's sometimes nice to feed a vocal through a distorting guitar amp, but I bet this gets very annoying if sustained. S/N ratio is the next thing to consider. just my opinion, YMMV regards Jochen @Ian No, I haven't heard of that. But that's a nice idea! Too bad I don't even have a good tube amp :-((((( Not much money, so the preamp's good enough. Fine. I won't do it. So should it have distortion or not? I'm torn between the ways. Or should I just go ahead and build separate pre's? Use one for mics and the other for guitars? My personal opinion is this: I need a mic pre, with preferably Lo-Z and Hi-Z inputs, and that's what I'm going to build. If I want to try distortion, I'm just going to crank up the volume until I hear something resembling what I want. Could I create a negative feedback loop for mics, and then put a switch somewhere to disconnect it (and allow distortion to occur)? Just a thought. |
#22
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Building my own preamp
How to build my pre? Let me count the ways... :-)
SS is about as popular as communism. I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? |
#23
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Building my own preamp
gjsmo schrieb:
How to build my pre? Let me count the ways... :-) SS is about as popular as communism. this was not from my posting... I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? shooting sparrows with cannons. A decent 1/2 lbs power supply with enough beef can be built for less money. IMHO 600V is much too much. 350V is plenty there. regards Jochen |
#24
Posted to rec.audio.tubes
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Building my own preamp
On Oct 24, 3:21*pm, jh wrote:
gjsmo schrieb: How to build my pre? Let me count the ways... :-) SS is about as popular as communism. this was not from my posting... I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? shooting sparrows with cannons. A decent 1/2 lbs power supply with enough beef can be built for less money. IMHO 600V is much too much. 350V is plenty there. regards Jochen it's adjustable, up to 600V... you're right about that, but it seems to operate ok, although I'm not sure if it's good to do that (there's a total of 3 power tubes). But you really think I could build a good HV power supply for less than 50 bucks? and half a pound? that's new to me. I look for "HV power supply" and "350V power supply on google. no luck. Is 50 mA @ 320V enough? I did find http://www.elecfree.com/electronic/p...-10-350v-50ma/ .. |
#25
Posted to rec.audio.tubes
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Building my own preamp
gjsmo schrieb:
On Oct 24, 3:21 pm, jh wrote: gjsmo schrieb: How to build my pre? Let me count the ways... :-) SS is about as popular as communism. this was not from my posting... I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? shooting sparrows with cannons. A decent 1/2 lbs power supply with enough beef can be built for less money. IMHO 600V is much too much. 350V is plenty there. regards Jochen it's adjustable, up to 600V... you're right about that, but it seems to operate ok, although I'm not sure if it's good to do that (there's a total of 3 power tubes). But you really think I could build a good HV power supply for less than 50 bucks? and half a pound? that's new to me. I look for "HV power supply" and "350V power supply on google. no luck. Is 50 mA @ 320V enough? I did find http://www.elecfree.com/electronic/p...-10-350v-50ma/ . Although this on would fit your purpose perfectly in regards of voltage and power, i'd still regard it a bit of overkill, (current limiting, metering why'd you need that in a preamp...). 320-350V @50mA is the range i'd expect for a single channel. For the first crapshot i'd take a small transformer with heater and HV winding - tube radio or replacement comes into mind, a few diodes resistors and caps and you're finished. I don't think the "original" power supply of the altec contained anything else. If you really want a regulated HV, there are some other suggestions in the book where the scheme you posted is coming from. this transformer might fit although the vendor is in germany.. http://www.tube-town.net/ttstore/pro...VA-Preamp.html ok i have to correct my statement, the TX already has 530 grams, so it would be 1 1/2 lbs. regards Jochen |
#26
Posted to rec.audio.tubes
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Building my own preamp
On Oct 25, 4:55*am, jh wrote:
gjsmo schrieb: On Oct 24, 3:21 pm, jh wrote: gjsmo schrieb: How to build my pre? Let me count the ways... :-) SS is about as popular as communism. this was not from my posting... I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? shooting sparrows with cannons. A decent 1/2 lbs power supply with enough beef can be built for less money. IMHO 600V is much too much. 350V is plenty there. regards Jochen it's adjustable, up to 600V... you're right about that, but it seems to operate ok, although I'm not sure if it's good to do that (there's a total of 3 power tubes). But you really think I could build a good HV power supply for less than 50 bucks? and half a pound? that's new to me. I look for "HV power supply" and "350V power supply on google. no luck. Is 50 mA @ 320V enough? I did findhttp://www.elecfree.com/electronic/power-supply-regulator-10-350v-50ma/ . Although this on would fit your purpose perfectly in regards of voltage and power, i'd still regard it a bit of overkill, (current limiting, metering why'd you need that in a preamp...). 320-350V @50mA is the range i'd expect for a single channel. For the first crapshot i'd take a small transformer with heater and HV winding - tube radio or replacement comes into mind, a few diodes resistors and caps and you're finished. I don't think the "original" power supply of the altec contained anything else. If you really want a regulated HV, there are some other suggestions in the book where the scheme you posted is coming from. this transformer might fit although the vendor is in germany..http://www.tube-town.net/ttstore/pro...p2192_Ringkern... ok i have to correct my statement, the TX already has 530 grams, so it would be 1 1/2 lbs. regards Jochen sorry 'bout this... but for me that fails on so many levels. One: I'm in the USA, which means I need a step-up, not step-down transformer (shoulda told you that) Two: I ain't in Germany, and I ain't paying for shipping Three: I have no euros. Anyways, if something like that is what I need (but USA version), then what about http://www.tubesandmore.com/scripts/...?item=P-T269AX I'd need two (or is it four? I think you can get away with two using the center tap) big diodes. 1.6 lbs, $42.20. I'd probably want a minimally regulated output... maybe. Or not. Whatever. If I don't really notice a difference in volume, the forget it. I'm still not really sure about which preamp design to use, so I'll wait on the power supply. |
#27
Posted to rec.audio.tubes
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Building my own preamp
gjsmo wrote:
I want to build a dual mic preamp, but I'm not really sure where to start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. So you don't want a particularly quiet mic pre then ? There are some sites online that have mic pre circuits from Telefunken, Siemens et al that were made for the German broadcaster WDR in the 50s and 60s to fit standardised equpment racks. These are probably some of the best tube designs around to date. US mic amps tended to be somewhat simpler. Check out ...... http://www.google.co.uk/search?hl=en...meta=&aq=f&oq= That will give you some model numbers to search for. The V72 seems to be quite popular with today's tube sluts. Here you go ...... http://audio.kubarth.com/rundfunk/index.cgi Graham |
#28
Posted to rec.audio.tubes
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Building my own preamp
gjsmo schrieb:
On Oct 25, 4:55 am, jh wrote: gjsmo schrieb: On Oct 24, 3:21 pm, jh wrote: gjsmo schrieb: How to build my pre? Let me count the ways... :-) SS is about as popular as communism. this was not from my posting... I beg to differ... unfortunately, most music these days is digital. On CDs, or (ugh!) MP3s. I confess to using an iPod touch for my music. Not that I like it, but then again, I can't fit 20+ LPs plus a player and small headphone amp in my pocket. Solid-state is about as popular as white bread (and just as bad). I still bet you don't want to overdrive them and use them as a distortion unit. IMHO this sounds like crap Ok, then I won't. So I guess the altec "electric crayon" is just fine, then? Or should I keep looking (I'm a bit new to audio equipment, but that really doesn't prevent me from knowing good sound when I hear it...) If this helps, I have a 600V 500mA max tube power supply. It needs a new pot for the bias, but it'll provide A voltage, B voltage (up to 600V) and C if I fix the pot (I think it's 0 to -150V). It's really big though, and weighs about 50 pounds, and needs a 6336 tube which costs 50 bucks. I think that would work for a power supply though, don't you think? shooting sparrows with cannons. A decent 1/2 lbs power supply with enough beef can be built for less money. IMHO 600V is much too much. 350V is plenty there. regards Jochen it's adjustable, up to 600V... you're right about that, but it seems to operate ok, although I'm not sure if it's good to do that (there's a total of 3 power tubes). But you really think I could build a good HV power supply for less than 50 bucks? and half a pound? that's new to me. I look for "HV power supply" and "350V power supply on google. no luck. Is 50 mA @ 320V enough? I did findhttp://www.elecfree.com/electronic/power-supply-regulator-10-350v-50ma/ . Although this on would fit your purpose perfectly in regards of voltage and power, i'd still regard it a bit of overkill, (current limiting, metering why'd you need that in a preamp...). 320-350V @50mA is the range i'd expect for a single channel. For the first crapshot i'd take a small transformer with heater and HV winding - tube radio or replacement comes into mind, a few diodes resistors and caps and you're finished. I don't think the "original" power supply of the altec contained anything else. If you really want a regulated HV, there are some other suggestions in the book where the scheme you posted is coming from. this transformer might fit although the vendor is in germany..http://www.tube-town.net/ttstore/pro...p2192_Ringkern... ok i have to correct my statement, the TX already has 530 grams, so it would be 1 1/2 lbs. regards Jochen sorry 'bout this... but for me that fails on so many levels. One: I'm in the USA, which means I need a step-up, not step-down transformer (shoulda told you that) Two: I ain't in Germany, and I ain't paying for shipping Three: I have no euros. Anyways, if something like that is what I need (but USA version), then what about http://www.tubesandmore.com/scripts/...?item=P-T269AX I'd need two (or is it four? I think you can get away with two using the center tap) big diodes. 1.6 lbs, $42.20. I'd probably want a minimally regulated output... maybe. Or not. Whatever. If I don't really notice a difference in volume, the forget it. I'm still not really sure about which preamp design to use, so I'll wait on the power supply. ...i thought it'd b a nice example of a small leightweight transformer. Of course i did not thonk you'd order one in europe. your example is quite nice and could power two channels easily. I can't see th dimensions, but one of the nice things about thos toroid donuts is, that they fit in a 1U case. regards Jochen |
#29
Posted to rec.audio.tubes
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Building my own preamp
Eeyore wrote:
gjsmo wrote: I want to build a dual mic preamp, but I'm not really sure where to start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. So you don't want a particularly quiet mic pre then ? Why does his statement preclude the ability to make a quiet mic pre? Cheers Ian |
#30
Posted to rec.audio.tubes
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Building my own preamp
gjsmo wrote:
mega snip I'm still not really sure about which preamp design to use, so I'll wait on the power supply. Instead of all these worries about what power supply to use and where to get the transformer, why not start in a more straightforward fashion and build a kit? Look he http://www.paia.com/ and search for their 9407K kit - its less than a hundred bucks. Cheers Ian |
#31
Posted to rec.audio.tubes
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Building my own preamp
Why does his statement preclude the ability to make a quiet mic pre?
It doesn't. In fact, I'd like a very noise-free preamp. I suppose I'm getting ahead of myself, since I don't care so much about regulated power - which will give me hum. I still have that regulated beast. With regards to the Aikido pre, could you PLEASE tell me why we are going through the trouble to regulate HEATER voltage? In a 12A[TUX]7, the heater is not part of the audio path (not directly, at least). It's just there to heat the plate. And the PAiA preamp seems like more than I would spend just ordering parts. Am I nuts? Because I really have no knowledge of good prices for tube stuff, but I sure know I like it (look up the Line 6 HD100 guitar amp head - it's beautiful, and the distortion is SWEET). If I wanted to do that, I think I might just get a Behringer preamp/DI box (http://www.behringer.com/EN/Products/MIC2200.aspx). It's guaranteed to work, too... although there would be no distortion, for sure. |
#32
Posted to rec.audio.tubes
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Building my own preamp
gjsmo wrote:
Why does his statement preclude the ability to make a quiet mic pre? It doesn't. In fact, I'd like a very noise-free preamp. I suppose I'm getting ahead of myself, since I don't care so much about regulated power - which will give me hum. I still have that regulated beast. With regards to the Aikido pre, could you PLEASE tell me why we are going through the trouble to regulate HEATER voltage? In a 12A[TUX]7, the heater is not part of the audio path (not directly, at least). It's just there to heat the plate. To remove hum and noise from the heater circuit, probably, so they don't get transmitted by various means to other parts of the circuit. Regulators are cheap and easy. Ian And the PAiA preamp seems like more than I would spend just ordering parts. Am I nuts? Because I really have no knowledge of good prices for tube stuff, but I sure know I like it (look up the Line 6 HD100 guitar amp head - it's beautiful, and the distortion is SWEET). If I wanted to do that, I think I might just get a Behringer preamp/DI box (http://www.behringer.com/EN/Products/MIC2200.aspx). It's guaranteed to work, too... although there would be no distortion, for sure. |
#33
Posted to rec.audio.tubes
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Building my own preamp
Ian Bell wrote:
Eeyore wrote: gjsmo wrote: I want to build a dual mic preamp, but I'm not really sure where to start. I've got many 5963's (industrial 12AU7's) and 12AX7's lying around that I'd like to use. So you don't want a particularly quiet mic pre then ? Why does his statement preclude the ability to make a quiet mic pre? State of the art semiconducors ( not necessarily even exensive ones ) can be stunningly quiet ( sub 1nV / sqrt Hz ) and can be direct coupled to the mic avoiding the cost and 'distortions' of an input transformer. For a really good input transformer look at Lundahl or Jensen. I know Lundahl have one designed to match to tubes with a high turns ratio and they know how to layer their windings for optimum performance. Graham |
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