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[quote author="matthias"]hmmm...


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mat[/quote]


Vhere ist de iron??? Vhy ist dist unit hav no iron but still sounds good?

Sorry not trying to open a can of worm but just very curious.........iron facktor??
 
Well, this unit does not have any iron and sounds marvellous.

Many transformerless units are like this.

Cranesong, Forsselltech, Millenia, all make high quality transformerless units.

What about the SSl compressor clone everybody likes in here?

This GML is said to be the most transparent compressor of all times, so iron would not be a good thing in here, for a transparent sound, unless very hight quality, big Lundahls with high level handling were used, but why not to go transformerless then?
 
Hi and welcome Mr.Massenburg!

Great to have so many respected designers around here.

I sincerely hope that all knowledge shared and learnt on this board is not exploited by anyone - lurkers or regulars.

Regards Tom
 
[quote author="StDomingo"]There's a very strong case that all "clean" audio designs should avoid transformers except where absolutely neccessary[/quote]
...And most audio designers seem to avoid me... unless there's no choice.

...perhaps I'm a transformer...

bibble.

Keef
 
> all dedicated to the continuation of excellence in audio electronics and who have a healthy interest in historic designs.

Well, not quite "all". Didn't this thread start with "I would love to reverse one of those..."? Maybe it was just respect, or maybe he thinks he can DIY it cheaper than $30 (unlikely to be "equal" without a LOT more effort than a $31 eBay bid).

And there are in fact people here who realize that the guts of some current $2,000 boxes are $200 in parts, and clone them. Since the final box has a proven (people pay) $2,000 value, and there is considerable design labor (and yes, marketing) to bring it to that state, cloning such boxes is obviously ripping-off the originator, just as much as ripping copies of CDs for your friends. (oh, we don't do that... sure.) And a superficial copy of something as subtly detailed as fine audio equipment is likely to NOT be as good as the original. Sometimes very small changes, even millmeters of layout, make the difference between fine wine and piss. The ear is a very sensitive instrument.

GM> there's something about this idea that's provocative and imaginative.

More to the point: the art of analog design, and especially audio design, good clean producable predictable design, is being lost. In my youth, any senior technician could sketch and build about any box in a radio or recording studio, from general knowledge, and it would work. Fewer and fewer people have that skill any more. Fewer people work in the field, publish less, the knowledge is held by a few designers.

My interest is in new designs. To be frank: I live not on the fruit of my brain, but by being at work 35 hours a week and being paid a salary. So my real interest is gizmos that let me do my job and put in the hours without actually working too hard. Like combining 70 pounds of preamps and limiters and cables into a 3-pound 6"x6" all-in-one box. With 2-stage limiting so if I doze off, it will look after my levels without gross distortion, thumping, pumping. While I look at the designs of others for knowledge, nothing is quite right so the design is as original as anything in audio can be.

But what is original? Nearly every good idea in audio arose by 1930, modestly modified by transistor maturity in the 1950s, with economic shift as chips swallowed dozens of transistors. In My Humble Opinion, "progress" since the 1970s has been modest. Mostly weeding-out the worst of the New Ideas (often old ideas once rejected and later re-accepted). And refinements of "old ideas", which can be a real art in itself. And of course seeing what you can do with newly-developed parts.

> I sincerely hope that all knowledge shared and learnt on this board is not exploited by anyone - lurkers or regulars.

Me too... but that's not human nature. Why are we here except to learn things we can "exploit" to our own good? There may be a moral difference between imitating an old design no longer sold, and copying a current design because we are too cheap to buy it. But as a practical thing, there's no difference. And "hoping" that nobody loses in the knowledge exchange is naive.

Even so: I think there are many things that George and Gyraf and Winston can teach us, without undercutting their own intellectual property and income. Some rather basic things that become "obvious" if you study and work in the field daily, that take a long time to grasp when designing as a hobby or on the side from a recording business. So I hope they share what they can.
 
This has been brought up in the past but I think its pertinent to this discussion-

I dont think there are any boxes that anyone here makes that are EXACT clones of anything that is currently commercially available that would thus result in a loss of revenue for a manufacturer. Please correct me if I am wrong. Take the popular things people make- 1176, SSL quad, API whatever, Neve whatever, etc. In the case of the Gyraf projects, the 1176 for instance is spec'd for lundahl transformers or a transformerless input, two things that you are definitely not going to get by purchasing the UA "reissue". This may seem like splitting hairs to some people, but Im sorry, if you want the classic 1176 sound, you arent gonna get it with a lundahl output transformer and also, the gyraf is a version of the 1176 (with the 1109 output) that if you wanted that output stage, you'd have to buy used anyway- the UA "reissue" uses the 1108 class A output stage. So, while you can look at it as a loss of sale, I think thats silly since youve built a box that is similar in name only. The same can be said for the gyraf SSL project, which has a different sidechain, different VCA's. There is also someone ALREADY cloning this to the same degree of "different" commercially. The same can be said of API preamps in the case of OSA and take your pick ad naseum with people cloning Neve circuits commercially.

The bottom line I have always thought and feel now more than ever is that any sale that a company claims to have "lost to DIY" was a sale they were never going to get, plain and simple. It does not save me a dime to make something myself than it does to go buy the thing pre assembled, I have built more than half of my input in my studio and can say with confidence that I have not saved one half of one cent by doing this shit myself. I DIY the stuff so that the only thing I have to answer to is the sound that comes out of the box, not the bottom line that an accountant referenced when approving parts selection for transformers and capacitors. I can put expensive parts in there that make me happpy and thats the end of it. Its not that Im too cheap to buy some commercial product, please adjust your ego and realize that I DONT WANT your commercial product that is full of Xicon caps and cheap pots and cheap switches. If a company either copied an old defunct classic companies design or a company built something based off a reccomended data sheet applicaiton or ressurected something cool from the pages of a radio engineer's handbook from the 50's- if someone can copy another's designs and capitalize on it, certainly I can copy that exact same design and build one for my own use with out having to worry about public opinion.

This certainly does not apply to everyone out there, as we all know, there are amazing people *designing* amazing stuff out there. Whats real wierd to note is that these guys that are busy desinging NEW designs and implementations are the dudes who participate here and are completely forthcoming with trying to help a newbie like myself pull up his bootstraps with electronics. Its generally the companies that dont have designers at the helm and are using widely published designs as their "own" who gripe about us building our own gear.

I dont know, perhaps my view on things is a little askew, but I just dont see how people like us appear to be points of loss of sale for manufacturers. I think anyone claiming that really doesnt understand the motivation behind this at all. Im not trying to build something because Im too cheap to go buy somebodys product. Im building something because somebody's product is too cheap to buy. Please try to understand this perspective. Im a recording engineer, Im a complete control freak and I like to know that the coupling cap that all my sound has to go through is in there not because I got a good deal on 10,000 parts that month but because I thought it sounded good, per MY taste compared to the six other caps I tried there. I built a box that is completely custom to MY tastes, what I thought sound good and all of this works with my business plan, people come to my studio because they know its filled with shit they can only use HERE because much of it is hand built and tweaked. Anyone can go anywhere and record on whatever commercial gear and get the same sound again and again.

Another perspective to consider is the fact that I actually ENJOY doing this. Yes, I really like putting the parts through the holes in the board, soldering them in, doing the wiring and reveling in a great feeling of accomplishment when I turn the thing on and it works. The problem that I have, unfortunately for now, is that while Im a smart guy, Im just an assembler and I couldnt design boo on halloween. If I want to build something for my zen hobby, Im more or less forced to build something that is proven to work, just so I know that when Im done, if it doesnt work, then Ive done something wrong because the design was proven to work. Believe me, I cant WAIT to have the knowledge to design my own stuff, if it wasnt for my ability to build and learn from others designs, I wouldnt be halfway down the road in that process.

Now, when I DO design something, if I intend to profit from that design and not give it away to the public domain, the last thing I think I would do would be to share it here, or anywhere else online. Posting something on the internet does constitute publication... Im not afraid of anyone HERE building my designs, theres actually nothing Id love more than to give back something concrete to all the folks here who have helped me so much, no, if I was intending to profit from my design, I wouldnt publish it online in fear of my competitors using something like it in THEIR designs and that is really the bottom line here- the people from commercial entities are not really concerned with guys like me building their shit, they are concerned about their designs floating around online so that their competitors can see what they are doing. As if to suggest that their competitors have purchased their products and back designed them anyway, but thats a different conversation... If more people would be more straight with this group, when this exact issue has come up in the past, I think more people would have more respect but screaming and yelling that WE are the problem is beyond absurd and shows a real lack of not understanding the TRUE economics of this situation, not the extrapolated and hypothesized economics coming from an accounting department.

What would really be a good poll would be a show of hands as to how many people here have built something for themselves that is commercially available in the first place. I think ultimately this is nearly a %100 non-conflict with any company that might be upset with the DIY community as the grapevine might suggest if you listen closely. There are VERY few things discussed here that you can roll out to the store and purchase in the form that we discuss them. As mentioned, the gyraf 1176 and SSL are different. The gyraf pultec is different and you cant go buy a new pultec anyway, anyone who is selling a new pultec is just cloning someone else's design in the first place. You cant go and buy an api 312. You can buy a 512, but I dont like the sound of that circuit at all with a 1:10 jensen, I dont want a 512. I want a 312.... You cant buy any melcor gear. You cant buy any Quad Eight gear. You cant buy a gyraf microphone, if its based on an old transformer balanced neumann design, you cant buy one of those from neumann, all the neumann tube mics are transformerless. You can buy a clone of a neumann design from a handful of manufacturers, but now we are back to that catch 22 once again. People are currently discussing FF's optical limiter which by the time we get done throwing ideas around will be unlike any optical limiter you can go and purchase today. Just about the only thing I can think of in regards to this group cloning a commercially available product would be a neve 1081. For the amount of time it will take me to build one of those, it woudl be cheaper to buy one....

I dont know, have I made my point? Am I completely off my rocker? We arent doing anything that screws with anyone's business outside of making DIY popular. Oh boo hoo to that. And the few occasions where someone has posted a schematic of something that was intensely proprietary it was immediately taken off this group accompanied with mass scolding and hysteria.

You know, there's only 7 notes in western music. There's only so much you can do with that. Thank god we dont have old blues guys crying from the rafters about nobody being able to use a 12 bar format or paul mccartney threatening to sue because you put a D chord after an A.

dave
 
I've been mulling the idea of a group DIY branching out into true DIY for a while. Rather than simply cloning & "ripping-off", we certainly have enough combined talent here to design, develop, share & build original, enlightening and edifying stuff.

Jakob has done a little of that for us, but the most fruitful true Group DIY that I recall has been the PRR 12AU7 compressor, which (with the help of Kent) has evolved into a highly-buildable project, and I would encourage those amongst us making boards for projects to concentrate future offerings on this sort of thing.

I might have something to offer the group on this: A while ago I built a working PWM "chopper" gain element with fairly accurate gain reduction indication on a regularly marked VU meter. -If anyone would like to take the cigarette-packet sketch that I made of how I saw it evolving into a compressor, I might be talked into 'donating' it into a group project, as long as there was reasonable sincerity in seeing it through... I'd hate to unveil it and have it "die on the vine" as it were.

Anyone else?

Keith
 
You know, there's only 7 notes in western music

I have to disagree with this statement. Ther is acctually 12 notes in western music. And I´ll not discuss it.

But good point about DIY and it´s implications with the commercial pro audio market.
 
I can definitely see and understand all the points being made here.

I think PRR hit it right on the head. I have often wondered why, with all the incredible talent we have here, there aren't more original designs being proposed. Maybe with this new board and the recent changes, we can also start with the new idea of creating original designs, like they're our own special brand. Why not?

I'm no designer myself, but I got into this with the intention of ultimately creating some unique designs of my own. Like PRR, I do not want to see analog design skills die out.

So what would help us accomplish this goal? Does anyone have any ideas for web applications or anything like that that would help? If there is one thing I can do now, it's code up some PHP and design databases.
 
When is something not based from something else?

The c800g type microphone was built because a friend needed a high headroom microphone for a opera singer, when I got done with the microphone it was no longer needed. I also built it because it used a 6au6 a tube not known for being good in a microphone. On the way we learned it was not a real 6au6 but a russian close to 6au6. We learned about noise and grid R. And underheating. The IR pictures were used to see the heat buildup at different heater voltages. Heat can cause outgassing in glass and in tube microphones extra noise.

Keiths posts about the neve IC based great having an offset to keep the electros in good shape. This is clone stuff that we learn from.

Zebra posted for me a schematic of a tube microphone using a fixed led bias and var sensitivity and pattern. Kind of a blend of u67 without feedback mixed with the fixed bias of a u47 but instead of a resistor and a dropping resistor from the 105V. I used a led and some "helper" current from the heater supply. The led having a somewhat "fixed" voltage drop allows the heater voltage to be changed without changing the bias voltage(note it is now red not amber). This allows underheating and maybe the cooler thing allows the B+ to be dropped to change the heatroom etc. It also has rear skin disconnect switch. It is about 1/2 done need to build the power supply and the body the body and tube are going to look a little different. Is this a hybid clone or a new design?

If I was to build a LA2 it would have a SS side chain and maybe a different gain makeup stage. I liked PRRs idea for a tube and solid state fairchild.

I read in a mastering book that someone uses a modded la2 no output transformers unbalanced for mastering this might be a cool DIY project.

I think some off us are not just building clones. But to learn clones can be a very good thing.
 
I read in a mastering book that someone uses a modded la2 no output transformers unbalanced for mastering this might be a cool DIY project.
I believe that might be the "Mastering Lab". Those mods might possibly be the work of either mr. Robert Neil, or perhaps the venerable mr. Bud Wyatt. -I've met them both several times, and often at the same time. -I seem to remember that it was one of them that told me they did that, but I can't remember which of the "Bob 'n' Bud Twins" it was! :green:

Actually Bud is someone who I have an immense amount of respect for. I spoke to him on the phone last week, and I think I might see if I can talk him into lurking or possibly even sharing some ideas here. -While it would be unreasonable to expect anyone who makes his living designing and selling the fruits of his wisdom to freely share that which is dear and precious to him, it would be fantastic if he were able to occasionally enlighten us with his thoughts, experience and/or suggestions.

Keith
 
[quote author="Winston O'Boogie"]So, where were we now?...Oh yes :idea: I remember---GML OP-AMPs
I just received, in the mail today, a pair of GML 8802 Op-Amps (a big thank you to you know who you are) These are coated in green epoxy and have the little 'GML Discrete OP-AMP' sticker on them. When I get some time I'll build up a jig to see what's what, 'what-what!'
While I'm at it, does anyone want the Schematic, BOM and the testing/matching procedure when I'm all done?... anyone? I'm just pulling your leg George :wink: but it will be nice to see how they compare to other types. That, and I felt like having a bit of a gloat, for what it was worth.

John aka W.O'B.[/quote]

John,

Obviously George doesn't want ti to happen, but if you do reverse those, I'd love to see the schematic. I'm not going to make a product out of it or anything, I just wanna know. ;)

Mark
 
[quote author="SSLtech"]I've been mulling the idea of a group DIY branching out into true DIY for a while. Rather than simply cloning & "ripping-off", we certainly have enough combined talent here to design, develop, share & build original, enlightening and edifying stuff.

Jakob has done a little of that for us, but the most fruitful true Group DIY that I recall has been the PRR 12AU7 compressor, which (with the help of Kent) has evolved into a highly-buildable project, and I would encourage those amongst us making boards for projects to concentrate future offerings on this sort of thing.

I might have something to offer the group on this: A while ago I built a working PWM "chopper" gain element with fairly accurate gain reduction indication on a regularly marked VU meter. -If anyone would like to take the cigarette-packet sketch that I made of how I saw it evolving into a compressor, I might be talked into 'donating' it into a group project, as long as there was reasonable sincerity in seeing it through... I'd hate to unveil it and have it "die on the vine" as it were.

Anyone else?

Keith[/quote]

This is absolutely why I'm into DIY! That's how I am with my guitar amps, I like new ideas. For me I'm less into compressors and EQs as so much of this can be done in DAW these days, (though I'll probably build an LA2A clone). But I'd really get into a group DIY design from scratch mic pre, if it was transformer in and out with either tube or discrete solid state design, that of an original microphone idea. You know, probably the most usefull would be to design our own discrete opamp, we could use it in everything!

Kelley
 
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