stormm64bar
New member
need any help i can get.. schematics,parts,details,etc
Building a tube condenser mic ??
- Thread starter stormm64bar
- Start date
Blue Jinn
Rider of the ARPocalypse
1. What is your budget?
2. Are you looking to build from scratch (including machining your own body) or looking to use an existing microphone as a donor and/or modification platform?
3. What is your skill level in reading a schematic, soldering, etc, and what if any kind of test equipment do you have?
4. What is your goal? Save money, satisfaction of doing it, both?
You can get a kit from Aurycle for about US$180.00 (extra if you need it shipped outside the USA) the circuit is similar to the Apex 460. They also have a multi pattern kit. These use a 12AX7, but there are many many well documented modifications to the basic design.
You can modify the MXL 2001 with the "Royer Mod" a 5840 design, and a circuit similar to a Swedish TELA 12 with a higher B+.
You can modify various commercial tube microphones with capsule and circuit upgrades, with a wide range of part choices at various price points.
There are two well documented projects at GroupDIY, the G7 an EF86 based design, boards available from the "White Market" at GroupDIY, and the MK47, adapted from the U47 with currently available parts. There are complete kits (less body) for this design.
Google is your friend.
2. Are you looking to build from scratch (including machining your own body) or looking to use an existing microphone as a donor and/or modification platform?
3. What is your skill level in reading a schematic, soldering, etc, and what if any kind of test equipment do you have?
4. What is your goal? Save money, satisfaction of doing it, both?
You can get a kit from Aurycle for about US$180.00 (extra if you need it shipped outside the USA) the circuit is similar to the Apex 460. They also have a multi pattern kit. These use a 12AX7, but there are many many well documented modifications to the basic design.
You can modify the MXL 2001 with the "Royer Mod" a 5840 design, and a circuit similar to a Swedish TELA 12 with a higher B+.
You can modify various commercial tube microphones with capsule and circuit upgrades, with a wide range of part choices at various price points.
There are two well documented projects at GroupDIY, the G7 an EF86 based design, boards available from the "White Market" at GroupDIY, and the MK47, adapted from the U47 with currently available parts. There are complete kits (less body) for this design.
Google is your friend.
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stormm64bar
New member
my budget is 500 or less. I was planning on building from scratch except to put in a body from some mic i find broken and cheap on ebay..lol i have soldered before. but i would not say im skillful at it. just successful .. i have never read a schematic in my life..lol. my equip is a breadboard i just ordered. solder.. a multimeter I'm wondering if i should order or just pick up from wal mart.. i notice they vary in price alot. from 20 bucks to a couple hundred.. so. im wondering if there is a certain one i would need for this project.. i also have a circuit simulator program for the mac. and all of internet to learn as much about electronic reading i can.. and my goal is to build something that i can be proud of.. not something that just works.. and save money as well..lol.. i have seen the g7 project. im kinda looking for someone that has just completed a mic building project.. so i can get a rundown on what order i should be doing and learning things.. some ppl tell me i need to know how to read schematics and some ppl say just follow directions. .. so. this is where im at so far.. im also a member of a yahoo mic builders group.. and they share alot of good things.. but they dont always reply back. and they leave my email full of other types of projects.. it could be that i dont know how to work a yahoo group..ha! thanks for responding
Blue Jinn
Rider of the ARPocalypse
I'm going to assume by "500" you mean US$500.00
1. Reading a schematic is critical; with a tube mic you're dealing with high dc voltages; and ac and dc if you build your own power supply.
2. Cheap multimeters are generally pieces of crap. You don't need a $500 Fluke, but a $4.99 noname is going to be worthless.
Starting from scratch, less body, is a rather tall order, especially if you can't read a schematic.
If you start from scratch, you will also need to build your own power supply. You have to factor this into the cost. The Royer circuit is worth checking out. It uses a subminiature tube (5840) and the power supply uses a 24v transformer with a voltage trippler, and the circuits are not very complicated. You can fit this into a MXL 2001 type body, and those come up frequently used. His cathode follower circuit is even simpler, it's basically the tube and a slightly different PSU.
Modding has its own challenges, as you need to desolder parts as well, which can lead to damage to circuit boards. The Apex 460 is a popular platform to modify. I have two of them (unmarked OEM models) on the bench to modify. They are pretty cheap already, (US$190) and you can change the capsule, transformer, PSU, and tube for as little as US$200 or so.
The Aurycle is worth checking out. The circuit is pretty typical, (similar to the Apex 460-- consider it the same without pattern switching.) You can swap out the capsule and tube, and make some other minor circuit modifications, but you'll need some knowledge to do that and to understand why those changes make sense. The Aurycle only comes with the schematic, no step by step instructions either.
If you haven't done much DIY before, I'd encourage you to start simpler, with kits, like guitar effects first, before jumping into a microphone and a tube circuit at the same time.
There are quite a few places that sell guitar "stomp boxes" with well documented instructions. I learned a great deal putting together some kits from Craig Anderton's Electronic Projects for Musicians. Most of the kits are not available anymore, but the book is a great learning resource. He starts out with a "this is a capacitor, this is a resistor, this is what they do, this is the symbol on a schematic," and he explains the goingson in his circuits as well.
Search this forum as well. There are lots of mods. I have a couple documented, and will document my HST-11a when I get a chance to get started again.
(BTW, your post is damn hard to read. Paragraphs and capital letters would be nice.)
1. Reading a schematic is critical; with a tube mic you're dealing with high dc voltages; and ac and dc if you build your own power supply.
2. Cheap multimeters are generally pieces of crap. You don't need a $500 Fluke, but a $4.99 noname is going to be worthless.
Starting from scratch, less body, is a rather tall order, especially if you can't read a schematic.
If you start from scratch, you will also need to build your own power supply. You have to factor this into the cost. The Royer circuit is worth checking out. It uses a subminiature tube (5840) and the power supply uses a 24v transformer with a voltage trippler, and the circuits are not very complicated. You can fit this into a MXL 2001 type body, and those come up frequently used. His cathode follower circuit is even simpler, it's basically the tube and a slightly different PSU.
Modding has its own challenges, as you need to desolder parts as well, which can lead to damage to circuit boards. The Apex 460 is a popular platform to modify. I have two of them (unmarked OEM models) on the bench to modify. They are pretty cheap already, (US$190) and you can change the capsule, transformer, PSU, and tube for as little as US$200 or so.
The Aurycle is worth checking out. The circuit is pretty typical, (similar to the Apex 460-- consider it the same without pattern switching.) You can swap out the capsule and tube, and make some other minor circuit modifications, but you'll need some knowledge to do that and to understand why those changes make sense. The Aurycle only comes with the schematic, no step by step instructions either.
If you haven't done much DIY before, I'd encourage you to start simpler, with kits, like guitar effects first, before jumping into a microphone and a tube circuit at the same time.
There are quite a few places that sell guitar "stomp boxes" with well documented instructions. I learned a great deal putting together some kits from Craig Anderton's Electronic Projects for Musicians. Most of the kits are not available anymore, but the book is a great learning resource. He starts out with a "this is a capacitor, this is a resistor, this is what they do, this is the symbol on a schematic," and he explains the goingson in his circuits as well.
Search this forum as well. There are lots of mods. I have a couple documented, and will document my HST-11a when I get a chance to get started again.
(BTW, your post is damn hard to read. Paragraphs and capital letters would be nice.)
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stormm64bar
New member
that is very helpful. it seems i may need to increase my budget . and yes . 500 US was correct.
Blue Jinn
Rider of the ARPocalypse
Your budget can be $200-3000 depending on what you want to do. You can get parts from AMI Tab-funkenwerk to build an authentic U67 clone. You can pay anywhere from US$95 to over $500 for a capsule. You can get a SP-1 for $50 and use the body, you can get a EQU47 body for $300.
That said, I built the Royer for about $130 or so. $30 for the used 2001, about $5 for the tube, built the psu into an old computer psu box, about $20 for the PC boards, $20 for the mic transformer, the rest misc cable, plug, and resistors, caps, etc small parts. Some stuff I had on hand. I used a conventional psu with HV in and trafo's I had on hand. You can use Royers psu and point to point it with a $15 24v transformer.
I used no-name 12:1 transformers. YOu can get a good one from Cinemag for about $45 or so. So a Royer shouldn't run you more than $150-200. It's a great circuit. My B+ is 70v under load an issue I haven't looked into yet, but at that B+ sounds fine. It is a positive change from the stock 2001, even with the stock 32mm K67 style capsule. See my thread here: https://homerecording.com/bbs/special-forums/diy-mods-homebrew/royer-mod-starting-331451/2/
Like I said before though, you are dealing with high voltages, including mains voltages. If you don't really know what you are doing, don't start out with something like this. The risk of killing yourself or starting a fire or both are real.
That isn't meant to be an insult. You should learn to read a schematic and have a general idea of what capacitors, resistors, and transformers do, Ohm's law, and other basics first.
That said, I built the Royer for about $130 or so. $30 for the used 2001, about $5 for the tube, built the psu into an old computer psu box, about $20 for the PC boards, $20 for the mic transformer, the rest misc cable, plug, and resistors, caps, etc small parts. Some stuff I had on hand. I used a conventional psu with HV in and trafo's I had on hand. You can use Royers psu and point to point it with a $15 24v transformer.
I used no-name 12:1 transformers. YOu can get a good one from Cinemag for about $45 or so. So a Royer shouldn't run you more than $150-200. It's a great circuit. My B+ is 70v under load an issue I haven't looked into yet, but at that B+ sounds fine. It is a positive change from the stock 2001, even with the stock 32mm K67 style capsule. See my thread here: https://homerecording.com/bbs/special-forums/diy-mods-homebrew/royer-mod-starting-331451/2/
Like I said before though, you are dealing with high voltages, including mains voltages. If you don't really know what you are doing, don't start out with something like this. The risk of killing yourself or starting a fire or both are real.
That isn't meant to be an insult. You should learn to read a schematic and have a general idea of what capacitors, resistors, and transformers do, Ohm's law, and other basics first.
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HauntedAccount
New member
Learn the basics first, please. Working with voltage this high is not recommended for a beginner. You should learn to read schematics, it's vital if you're going to build something. I've been working with electronics for a while now and I'm still scared of working with mains. There are so much that can go wrong when you work with high voltage.
Blue Jinn
Rider of the ARPocalypse
It's not just mains either, but fairly high DC voltages as well. I've been working with electronics for a while now too, I still know only a tiny fraction of what the folks at GroupDIY know. I've made silly mistakes, like installing a capacitor backwards (more than once) noticed before I applied power, but that's the kind of mistake that goes BANG!
CAlbertson
New member
First off, the voltages used in tube equipment are lethal. Learning from your mistakes is not an option.
Might I suggest and easier first project? Build a small 5 watt audio amplifier with a built-in speaker. Something like a small guitar amplifier. This will be far easier.
Then your firs microphone project should not be a tube mic. Build something simple first.
Buy good tools. You don't ned the best but a $10 Wall mart multimeter is "junk". For building something as complex as a microphone you will need some more test equipment or how will you test it? Just plug it in try. So what if there is some disortion in the low bass range? How would you charagterize and repair that?
See what I'm saying, start on a simpler project.
mavericmanic
New member
You can buy a Tube preamp. Building one is possible but requires some knowledge of Electronics and Tube Theory. Try Google for a schematic and there is a lot of schematics out there that I have collected. - Stuart
mavericmanic
New member
I have to agree with the other posts that this is a big project and I modify and build Custom Tube Amps and it is tricky stuff. Even with a degree in Electronics, they do Not teach Tube theory in school. You have to read books about Tube Amps like Dave Hunter and Gerwald Weber. I have read (5) books so far and still do not understand it completely. - Stuart
I'm sorry Stormm but I really don't see the point?
Capacitor mics, even the valved jobbies are now so cheap that nothing you could make at home would compare for performance, bit like building your own monitors (and I have built more speakers than you have had hot dinners!) ...IF you have the equipment and years of experience, maybe.
I applaud the several safety warnings: There is a way to experience (not tactilely!) high voltages in relative safety. Buy two identical AC-AC wall warts. The secondary voltage does not matter so long as they are the same.
Now, connect one LV secondary to the other and plug one in the wall..Careful! Meter the pins on the second wart and you should have aproximately mains volts (tough if you are USA since 120V is not really enough for most valves, but there is a dodge) . The benefit of this setup is that it is so lossy and inefficient that you can not draw much current from the HV winding. But be warned! If you cop the pins in each hand and you are perhaps not in the rudest of health, heart could stop! The traffs should however give just about enough current to power my alter ego!
Basic electrical safety:
Only ever put ONE hand on a part of the circuit and don't even do that if you can avoid it.
Power off: Clip on test leads: Stand back: Power up: Read results etc.
NEVER work alone. Have a responsible adult within ear/eyeshot.
NEVER have kids or pets around.
NEVER, EVER work pissed.
Dave.
Capacitor mics, even the valved jobbies are now so cheap that nothing you could make at home would compare for performance, bit like building your own monitors (and I have built more speakers than you have had hot dinners!) ...IF you have the equipment and years of experience, maybe.
I applaud the several safety warnings: There is a way to experience (not tactilely!) high voltages in relative safety. Buy two identical AC-AC wall warts. The secondary voltage does not matter so long as they are the same.
Now, connect one LV secondary to the other and plug one in the wall..Careful! Meter the pins on the second wart and you should have aproximately mains volts (tough if you are USA since 120V is not really enough for most valves, but there is a dodge) . The benefit of this setup is that it is so lossy and inefficient that you can not draw much current from the HV winding. But be warned! If you cop the pins in each hand and you are perhaps not in the rudest of health, heart could stop! The traffs should however give just about enough current to power my alter ego!
Basic electrical safety:
Only ever put ONE hand on a part of the circuit and don't even do that if you can avoid it.
Power off: Clip on test leads: Stand back: Power up: Read results etc.
NEVER work alone. Have a responsible adult within ear/eyeshot.
NEVER have kids or pets around.
NEVER, EVER work pissed.
Dave.
Lt. Bob
Spread the Daf!
It's actually a pretty silly idea to want to start your first electronic project with this.
as ecc says .... there's virtually no chance you'll end up with a mic that performs as well as even a cheap prebuilt mic so you'll just be wasting money
I pretty much always disagree with these guys about the riskd. Yeah, you're likely to get bit (as all techs have from time to time) but the actual risk of death is pretty low. But still ................. you NEED to start with something simpler or you'll just be tossing money into the disposal.
as ecc says .... there's virtually no chance you'll end up with a mic that performs as well as even a cheap prebuilt mic so you'll just be wasting money
I pretty much always disagree with these guys about the riskd. Yeah, you're likely to get bit (as all techs have from time to time) but the actual risk of death is pretty low. But still ................. you NEED to start with something simpler or you'll just be tossing money into the disposal.
mavericmanic
New member
I got shocked (3) times in one day. Twice by 240 VAC from a transformer, and once by a VOX Amp 410 VDC and it hurt! I keep my left hand in my pocket to prevent current going through the heart. This is a Tech. Trick I learned both in school and in books about Tube Amps. Plus I work on HV on a wood bench and standing on carpet. It is the Mains I am more concerned about 120 VAC. - Stuart