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[Oliver Archut]

One of the greatest joy in the work field is, when self build ideas take shape, get planed and finally work and maybe even money was saved.
In the field of professional audio there has always been the DIY approach, either studio owner that could not afford the high dollar gear of the times, best known example was Sam Phillips, that build most of his studio as well as the gear like compressors himself, or radio station at the time, record company and many other studio owner counterparted the pricy specialty equipment of the time with home made stuff, that sometimes turned out to change the recording industry.

So what does that mean today? Can we still go out as a small studio/ or project set up and build the gear we want and still get everything done, even save money?
Maybe I should rephrase my question, because not just the music industry has changed, the entire world. So lets take a closer look.

What is mostly missing from the audio world today is the related field of electronic. In the 1950/60/70 the ham and radio field was still fully active and most teenage knew how to build a detector radio or later in the army general basics of radio were picked up.
Also in every town you could find a radio/TV repair shop were "Jack' could fix nearly everything, with or without schematic.

Keeping that info in mind and looking around today, nothing of the consumer electronics is fixable today so no "future" repair tech can get his feet wet with trying to fix or modify some consumer stuff!
The entire supporting electronic radio industries is missing, because some of the highly priced components today were standard parts in the 1950/60 and were so easy to get a hold off.

One of the reasons why I started making my own transformer was because the ones that were available were just "fair" and the manufacture could not offer satisfactory custom work.

In my view there is an big problem to hit the audio world in the next couple of years, and that is the lack of good techs that can fix everything that has a plug or a batteries.

I ask you all and hope that many people try to share their DIY or customizing experience... And maybe just exchanging some thoughts.
Because in the end only a good DIY project that works, and is nearly as good or same as good than the "wished for" gear make the DIY idea a good one...

[Barry Hufker]

Oliver,

I am not so sure we are going to run out of good techs any time soon.  There is a generation before us still capable of training others and repairing "fixable" gear.

It will be soon enough that there won't be a demand for such people because equipment will no longer require them.  What will be required instead are good programmers.  These programmers will be the ones to design new computer-based eq's, compressors, etc.

And this will be the new studio DIY.  If you don't have an EQ filter that does what you want, write one.  The same for all other gear.

As long as there is vintage gear, such as we have at the moment, there will be a demand for a traditional tech.

But before long, vintage gear will all be software needing repair lines of code or updated code or a microprocessor fix.

Barry

[Oliver Archut]

Hello Barry,

I see it a bit different, training is quite expensive these days and even we still have a generation before us, the old guys are hard to find and the info even harder.
Most of the older guys that really know their stuff won't even get a computer, so how can they teach the beginners?
There are so many shortcomings with repair guys these days. If it is just something simple like a broken switch, blown fuse this is not a problem, if there is a replacement part available still no problem but what is after that?

I deal with lots of DIY guys and repair techs, but most of them are following some links or someone's other idea without trying to get to the root. The is today a shortage of good magnetic/transformer repair guys, there is a shortage of good mechanical techs, etc.

Sure computer are everywhere and will take over more and more functions of the everyday life as well in the studio domain, but fixing the code is not all, getting into it that's computer box.... that is the problem.
There are programs of designing everything from x-formers to mic pres, but up to today none that does really cut it.

Maybe I am wrong, but for my part talking about a possible problem and being wrong is better than to ignore it....

Best regards,

[Barry Hufker]

Oliver,

Please don't think I'm saying this subject shouldn't be discussed.  Quite the contrary.  I think this topic is worth a full and complete thread.

I guess we're lucky at my university.  We have a wonderful tech, Bud Steward, who is an old tube/ham radio guy who is able to tackle (and succeed at) fixing just about anything thrown at him.  He knows his test gear.  He knows circuits.  He builds custom gear for us and is great to work with.

Barry

[Oliver Archut]

Hello Barry,

please do not understand me wrong, I hear you on what you say, and you are lucky to have Mr. Steward to you disposal, but my point is that in general good audio techs are quite rare. Without the DIY and radio/ham areas nearly missing it is hard for young guys that are looking to find a way into the repair/design field.
Lets hope to hear back from some guys....

Best regards,

[maxdimario]

This is true, there are techs but not AUDIO techs.

audio went downhill with the advent of the opamp.

after that anybody could produce an audio mixer or gear without having to deal with subtleties and the intrinsic problems found in discrete circuits.

IC engineers are a new breed, and usually do not have a classical audio approach towards design.

for instance, opamps are designed to run with power supply voltage inconsistencies, they are designed with a relatively low output impedance and relatively high input impedance, as well as having ruler-flat response and good specs..

all of this possible with a couple resistors and a cap as the only other components... and very little designing effort.

discrete audio is as much a philosophy and an art as it is technical, and it requires knowledge of details pertaining to the individual active components... be they tube or transistor.. it requires selection and it requires real-world tests.

IC opamps are built to behave identically regardless of interior tolerances..

I don't believe that computers will ever replace analog preamps.

a good analog preamp is not the same as a run-of-the-mill analog preamp with very good specs coupled to a digital algorhythm which adds 'euphonic distortion'.

it's not what gets added but what doesn't dissapear along the way which makes a fine preamp/amp.

the whole distortion thing is HIGHLY overrated.

[danickstr]

I think the difference in today's DIY shortage is the work of guys like Dan Kennedy and yourself, that make it silly for me to try to build something better, when you have already done it.  

Boutique techs have the net to spread the word, and hopefully for you sales are decent.  If I really wanted to solder something together, I think there are kits for that, at all levels.  

If I try to R&D something to challenge a piece that you and/or your contemporaries have tweaked for years with your vast experience, who am I fooling?  It will fall short of the mark.  It may be fun and if I already own a box of cap and resistors and PC boards and chemicals, and tube mounts, etc, etc, I may save a bit, but I would rather go to a seminar and have my ideas refined by someone like yourself before I jump into that arena.

And I don't think distortion is overrated.  Why else try to make classic circuits?  Accuracy is overrated.

[Oh! My Sea Captain!]

The problem I have with techs these days is that they won't teach me.


A Typical Conversation:

"Gee, sir, I'd really love to learn more about this stuff."

"You don't know what you're getting into, kid."

Anyone in Philadelphia want to hire me?    

[RMoore]

Oliver Archut wrote on Tue, 05 December 2006 17:36

Hello Barry, please do not understand me wrong, I hear you on what you say, and you are lucky to have Mr. Steward to you disposal, but my point is that in general good audio techs are quite rare. Without the DIY and radio/ham areas nearly missing it is hard for young guys that are looking to find a way into the repair/design field. Lets hope to hear back from some guys.... Best regards,

I think its definitely an issue - most of the techs I've encountered are getting on in years,with few or no youngsters moving up in the ranks,
There is however, one young tech at Funky Junk in London who seems very on the ball & in his 20's..
But like Oliver says, competent techs who have a lot of expertise with component level repair of studio audio gear are going to become very rare in the coming years as people retire, leave the Earthly plane etc,

[Barry Hufker]

The decline here was obvious when Heathkit went out of business.  For decades you could order one of their kits with numbered and illustrated instructions.  But devices became too complex in a sense and became cheaper/easier to buy than build.

I'm not sure what there is to excite someone about this area of electronics.

Barry

[Gold]

I am learning the Neumann lathe repair business. I spend a lot of time with an oldtimer who has been doing this from before I was born. The only problem is that I'm not a great tech. I'm more of an operator. I have learned a tremendous amount about it. I also love it. But this isn't general tech knowledge. I just know these machines very well.

[maxdimario]

Quote:

And I don't think distortion is overrated. Why else try to make classic circuits? Accuracy is overrated.

try and record a km56 or similar mic in a large reflective area as you strike a drum.

use a 'classic circuit' such as v72 or discrete..

now use a modern 'accurate' preamp..

listen..

chances are that the classic circuit will let you hear the room depth and reflections better than a modern, 'clinical' amp..

[Oliver Archut]

Hello Sea Captain,

before asking to get hired my advise is to learn as much about electronics as you can. The basics that apply to all fields are easy to pick up and DIY project (with the idea in mind becoming a repair tech) is still today very valuable today.
As I pointed out getting your hands dirty with radios or amplifiers (you can get great basic tube amp as a starter on ebay for $10 or so).
It would be great finding someone that can guide you in your quest, but applying somewhere without knowledge is pretty difficult because guys that can help you don't want to start at Ohms or Kirchhoffs law...

[mullytron]

Full-on noob here.  First post, but been making records, playing music, and fixing gear for 20 years.  Oliver, I met you and Josh at the TAB booth at AES-NY last year.  Howzit?

I know for a fact there are skilled techs out there, but I think the ones that are really "getting it" as far as working on and/or developing analog circuits in the digital age are not going to be tech's only.  They are likely musicians, studio owners, producers, modders, or a combination, who got lucky enough at some point to have a chance to learn and practice the art, to the point where they got skilled.

Which is great, but it's not the sort of broad-based skill set as it was before.  It's a similar situation as learning to play jazz, where it used to be a popular music that was in the air, and people learned how to play it because it was the dominant musical language of the day, not because it was a historical art form.  Does that make sense?  You can still generate very talented folks, geniuses even, but it's different approach now, when it's a conscious goal, as opposed to when analog electronics was simply the "way it gets done."

[Oliver Archut]

Hello Mullytron,

I know there are some great techs out there, but seven out of ten have their own company making new gear because there are so little companies left that make incredible gear. The other three are locked up in some studio/producer or corporate setting.

I do not agree with your Jazz thought, maybe it works for tube electronics, but there are hardly any techs that you can find their way through a solid state thing... Everytime my TV or another thing says goodbye I have a hard time finding someone that can fix it. Mostly everybody charges me for their time but the problem is always still there. My last Sony TV I finally threw out because none was able to fix it and after changing $250 worth of PCB I finally gave up and it went. Same with most of my "Modern" equipment that I do not have the time for to repair.

I still think it is a sign of the times and the little reflection we get here in the audio world is just a minor part of it. I still hope that some DIY guys will post their projects and maybe question here...

[mullytron]

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...

[James Craft]

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.

[Oliver Archut]

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,

[Martin Kantola]

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

[Oliver Archut]

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,

[Martin Kantola]

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...  




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

[synthi]

nice work!!  

Synthi

[Gustav]

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

[James Craft]

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.

[Oliver Archut]

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,

[gevermil]

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 ?

[Oliver Archut]

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,

[maxdimario]

Interesting that you chose 6k7's

what is the output circuit like on your compressor??