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Author Topic: Do it yourself projects in relation to saving money  (Read 14699 times)

Offline mullytron

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Re: Do it yourself projects in relation to saving money
« Reply #15 on: December 07, 2006, 08:58:24 pm »
Maybe I'm just not expressing myself well.  All I meant by using jazz as a metaphor for DIY electronics is that there are still people learning their way around circuits, but it more of a niche pursuit, or boutique if you will, specialized and focused.  

Likewise, jazz was once a living dialect, now it is (arguably) in some danger of becoming to some extent, a museum piece, or a re-enactment of its own historical self, instead of a new and ongoing extension.  (not trying to start a flame war, I KNOW there are modern practitioners of jazz AND electronics who continue to break new ground, but I would argue they are the exceptions)

Electronics understanding is no longer as much a part of the general world, in which many people as a matter of course are absorbing the practice and the process, putting into use on a regular basis, and thereby amassing the skills and expereince needed to develop a solid general understanding, let alone a unique personal approach or method that leads to truly "incredible" gear, as you say.  If anything, the IC engineer has taken over this position (or the programmer), as others have stated.  But it is hard to fab a DIY 14-pin DIP IC in your garage...

"If we knew what we were doing, it would not be called research."
 - - Albert Einstein

Offline James Craft

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Re: Do it yourself projects in relation to saving money
« Reply #16 on: December 10, 2006, 06:50:23 am »
I just went though a tube mic DIY under the tutelage of a tech friend of mine who goes back to the 60’s, Univ of Maryland, ARMY, boatloads of radio stations. We took an Apex 460, replaced the capsule (Peluso CEK-89), new transformer (Cinemag 2480) and a NOS GE 5-Star 6072A, basically gutted the mic. We modified the circuit removing the cathode-follower and changing a resistor here and there, still have a couple of caps I want to change (we didn’t have replacements available at the time), but the results were amazing.

We ended up going to another friends studio in Nashville where the owner was rehearsing with a singer/guitar player and we had this guy sing, play guitar & harp though it. As it happens there was another old friend I hadn’t seen in quite a few years who I talked into coming over that night so we could kinda hang out and he mentioned that he had an original U47 he could bring over so we could compare the results of our endeavor. The U47 definitely rocked and had the magic, but the modded Apex held it’s own and we were all very surprised. The modded mike had very similar tone on the vocal compared to the 47, but when the dude blew the harp the difference was that the 47 was better on the high end, a little more edge I might say, but it wasn’t a negative concerning the Apex, in fact I rather liked it compared to the 47 on the harp.

I had worked in my families or my own studio since I was 15 and over the years I had to learn how to repair my own gear out of necessity. Most of it was just replacing opamps and such because it was something that happened on a regular basis, particularly in my JH-24. I never completely understood the theory behind what I was doing and why I was doing it. This project has taught me a few things, especially about tubes and their operation in a circuit that I wouldn’t have known other wise. I am digging it to a point that I now have a box of parts that I am going to use to build my teenage son a kinda direct box based on a Fender Deluxe amp without the output stage, just adding a cathode follower to the preamp and taking an output to the sound card in his PC.
“You’re paid to record, not erase!” ~ an annoyed Jim Dickinson to young engineer who took it upon himself to clean up the bleed on some tracks.

Offline Oliver Archut

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Re: Do it yourself projects in relation to saving money
« Reply #17 on: December 11, 2006, 11:36:28 am »
Hello James,

thank you for sharing your DIY project, a pic of the mic would be great and maybe the overall cost and time. How it sounds you put your knowledge to good use and a good working DIY project is always better than the "standard" thing...

Best regards,


Oliver Archut
www.tab-funkenwerk.com

We are so advanced, that we can develop technology that can determine how much damage the earth has taken from the development of that technology.

Offline Martin Kantola

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DIY alive and well!
« Reply #18 on: December 12, 2006, 11:13:19 am »
Yes,

all these years we've done many DIY projects for my studio.

Surprisingly maybe it's always been 1% building and fiddling and 99% everyday use for these devices. They've definitely been worthwhile doing. Not only has it saved money, but given me some very useful tools not available in the shops.

Some examples of what we've designed and built:

- tube and solid state microphones
- instrument pickup systems
- DI boxes, passive & active
- tube mike pre's
- tube vari-mu stereo compressors
- hybrid class-A power amps
- class-A headphone amps
- speakers (including our own drivers, crossovers etc.)
- high-quality A/D and D/A converters
- guitar FX's
- water cooled studio computers (long before kits and parts were available)

I'd love to share pics or descriptions if somebody's interested in any of these above. My little DIY project of this week is sampling my own acoustic spaces.

Martin

Offline Oliver Archut

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Re: Do it yourself projects in relation to saving money
« Reply #19 on: December 12, 2006, 09:00:50 pm »
Hello Martin,

thanks for posting your DIY list and I am happy to hear that you get a good use out of them. IF you do not mind how about sharing some pics of the variable mu compressor.
The luminescent compressors a la LA2 and the diode bridge a la Siemens (mostly know because of Neve) are quite covered in DIY projects, but a good remote cut-off tube compressor is hard to do.
First getting a hold of a good circuit, and than the tubes and transformer(s), as soon as you got the unit ready the fine adjustment, etc., etc.

Best regards,



Oliver Archut
www.tab-funkenwerk.com

We are so advanced, that we can develop technology that can determine how much damage the earth has taken from the development of that technology.

Offline Martin Kantola

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The Compressor
« Reply #20 on: December 13, 2006, 03:23:49 am »
Oliver,

here's a bit of info on the compressor. Use it a lot, both for tracking (especially vocals) and as a stereo master compressor. One of the odd things about it is that it will work as an expander too. Great for cleaning up a snare or so. It also has a variable de-esser side-chain filter. If you're wondering about the cool front panel it's made of magnesium...  

index.php/fa/3856/0/


Tech specs:

Tubes: 6922 and 6K7
Input impedance: 20kOhms
Output impedance: 150 Ohms
THD(0dB gain): less than -60dB at 0dB, less than -40dB at +20dB
Frequency response: 20-20kHz +/-0.2 dB
Output noise (0dB gain): less than -100 dB lin.
Variable gain: +-20 dB variable
De-ess freq.: 1-10 kHz max.
Output level: +26dBu into 10kOhms  
Max. compr./exp.: 40 dB
Attack time: 0.02 ms to 200 ms
Release time: 0.05 ms to 5 s
Threshold: -40 dBu to +20dBu
Range control: 1.3:1 to 20:1
Power consumption: 50W
Dimensions: 3 U

Martin

Offline synthi

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Re: Do it yourself projects in relation to saving money
« Reply #21 on: December 13, 2006, 07:34:13 am »
nice work!!  Smile

Synthi

Offline Gustav

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Re: Do it yourself projects in relation to saving money
« Reply #22 on: December 17, 2006, 01:55:59 pm »
I diy to make stuff the way I want it.  It is not about saving money. It might be cheaper just to buy a few good microphones.  I have some nice bought microphones Brauner ,Gefell, Neumann.  It is also a good way to learn about things.

 I have built a few microphones and learned a lot about tubes and fets(I am still learning) to use and all the what at first might look like little things can make a difference in microphones.  I have learned a few things about microphones from hints and posts the web from You, SP, Klaus, David Bock, David Josephson and others whos names I am not remembering right now: However I test if I can what I read.

 I see pictures and words posted on the web about DIY, modded china built and even microphone companies microphones that seem to be wrong to me from the tests and builds I have made.  I have also seen picture of the insides of some microphones that I have not heard yet that look very well designed and thought out from tracing the circuit(fragment) looking at the PCB and brand parts used.

I have a few of your transformers and other brands.  I have different alloy ones amorphous, Mu and mixed alloy. I also have relammed a few china ones and might try winding one soon to learn from.  As you have posted over the years the alloys and winding do make a differece.  I test my tubes rp and tune other things at the final part of the builds.

I have a half built capsule, I stopped because my lathe is not true enought yet for what is needed to build a good capsule.  I want to build one, capsule to transfomer, just to do it.

I guess a lot of why I DIY is to learn.

Gustav


Offline James Craft

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Re: Do it yourself projects in relation to saving money
« Reply #23 on: December 17, 2006, 05:40:50 pm »
Oliver Archut wrote on Mon, 11 December 2006 16:36

Hello James,

thank you for sharing your DIY project, a pic of the mic would be great and maybe the overall cost and time. How it sounds you put your knowledge to good use and a good working DIY project is always better than the "standard" thing...

Best regards,


Sorry I took a bit to reply, having a little trouble with one of my eyes, something has come loose inside (I have had several surgeries on both eyes, so I'm not really freaked, go to the doctor in the morning).

Sorry I don't have any pics of the mic, my digital camera don't do close-ups well, might be the operator, maybe get some later.

Total cost of the mod was about $450 including the $200 I paid for the mic on Ebay. Time for the mods were just about 3 hrs, but we spent maybe 4-5 hrs modeling the circuit on circuitmaker to get the voltage at the plate where we wanted it and a few other things. Biggest hurdle was lack of a .mod file for the capsule, had to jury rig one with 2 45pf caps and a signal gen, but that was my buddies thing as he makes his living as a circuit/pcboard designer. As I said before we removed the cathode follower in the circuit, we changed the cathode resistor from 2.7k to 2.2k which set the plate voltage pretty much in the middle of the power supply's range and we removed the cathode by-pass caps. All of the parts were stock stuff available from Peluso, Cinemag and others, The 6072A is NOS GE 5-Star from "KCA NOS Tubes" and it tested righteous on my buddies Hickok tester, we also stuck it in a preamp he had on the bench and the noise and distortion figures were a few db better than what was in the pre. I have picked up some Panasonic 1000pf polys to replace the originals in the mic and I have a Solens 2.2uf/400v to replace the 1uf electrolytic from the plate to the transformer, which is gonna be a bit of a fit due to the size difference. Most of the info I got on modding the mic came from the forums at ProdigyPro and a little at GearSlutz (more of the idea here than solid tech info). There are a couple of mics in this genre suitable for modding besides the Apex, such as the Nady 1150 & 1050, so don’t hesitate to search for these and their info too.

This thing has really taken a life of it's own and PO'd my wife as I now have three cabinets on the wall over my desk with like 10000 resistors, mulitudes of caps and some tubes. I think I might have spent $300-400 for parts and a decent multimeter since I started this thing. I also now have a decent little stock of 200-1000meg resisters which most to most folks seem hard to come by.

This is also a pisser; my Dad started collecting tubes in the 50's and musta had almost 3000 tubes, around 1995 he gave them all away to some dude, geez, wish I'd known better.
“You’re paid to record, not erase!” ~ an annoyed Jim Dickinson to young engineer who took it upon himself to clean up the bleed on some tracks.

Offline Oliver Archut

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Re: Do it yourself projects in relation to saving money
« Reply #24 on: December 19, 2006, 10:23:35 pm »
Hello Gus,

good to hear that you still doing your DIY mics. It is quite funny that most people always make the capsule responsible for the sound of a microphone.
If you swap a BV8 (U47) with a M49 x-former you will get a mic that does not sound like a 47 nor 49 because of the different tube... It is quite interesting.

If you want to make your own x-former an old Sunbeam kitchen mixer is a good start, they have a pretty sturdy motor and have lots of torque due to the mechanical motor control. The beater can be easy changed over to a bobbin holder... And you can get them for a few bucks at every thrift store.

Lamination for mics are quite hard to get a hold of, because the standard American core are not the best (mechanical) size, and the alloy is off too. Let me know if you need just a few laminations and the needed bobbins...

Best regards,

Oliver Archut
www.tab-funkenwerk.com

We are so advanced, that we can develop technology that can determine how much damage the earth has taken from the development of that technology.

Offline gevermil

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Re: Do it yourself projects in relation to saving money
« Reply #25 on: December 23, 2006, 02:05:13 am »
Is there truth to the notion that older transformers used a higher quality metal than todays compositions ? All the cinemags , jensens and sowter (ect) replacement transformers for vintage gear don't sound like the original , even though they have the same dimensions and turn ratios , ect . Do older electronics just Age and mellow
like capsules  /  electrolytics  /  transformers and we adore them for this ?

Offline Oliver Archut

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Re: Do it yourself projects in relation to saving money
« Reply #26 on: December 23, 2006, 11:28:05 am »
Hello Gevermill,

we have to settle the terms reissue first,
a true reissue looks, fit and is identical build to the historic one. Given the fact that there are for most x-former several revisions, the "new" counterpart should be reissued to one of the historic counterparts. In those cases the x-former sounds identical.

Than there are replacements, they can be identical in lamination and winding technique but modern components for bobbin and wire leads/PC mount are used, the footprint might be different.

Most of the modern replacements are inspired by the historic ones, in all cases the winding ratio is the same but that's it, different winding technique, modern version of lamination has been used, etc. Sometimes the manufacture points out that fact with words like "general replacement", "as close as can be", "new mounting holes might be needed", etc.

I think I mentioned it before here, but the impact in sound on lamination and winding you can find with the Fender "Bassman" and the first Marshall "Bluesbreaker" guitar amps, the Marshall's are nothing else than a clone of the Fender, but with different transformers and other european replacements like different tube (6L6GB vs. KT66), etc.
Change all the exchangeable components back to American tubes, etc. and your Marshall still sounds like a Marshall, change the x-formers and you finally end up with a genuine Fender sound!

Regarding the difference in modern lamination look here...
http://recforums.prosoundweb.com/index.php/t/14634/1288/

Best regards,
Oliver Archut
www.tab-funkenwerk.com

We are so advanced, that we can develop technology that can determine how much damage the earth has taken from the development of that technology.

Offline maxdimario

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Re: Do it yourself projects in relation to saving money
« Reply #27 on: December 25, 2006, 07:49:39 pm »
Interesting that you chose 6k7's

what is the output circuit like on your compressor??