Tuesday, February 17, 2009

In a galaxy far, far away...before Pro Tools....

“Every console, I don't give a damn if it's analog or digital-hell, every mixing situation today-is the brainchild of Bill Putnam.” -Bruce Swedien



There are many arguments both for and against the home recording, digital recording revolution. I've heard most of them and they both have their points, though every opinion is just that, because ultimately music is music and a recording is just the style of documenting music. A crappy recording will still convey information almost as well as a great recording.
And with the onslaught of everyone, and their mother, having Pro Tools and booking time in the spare bedroom, I continue to try and learn about what makes a recording great.

Before the days of digital compression, internet forum interns, MP3s going to the mastering house and assistants who refuse to patch in a real 1176 because "the plugin sounds just as good". In the days when you actually had to KNOW about electrical engineering to engineer. Even before the rise of the cassette tape...

All the way back to where the modern recording studio started.
People like Bill Putnam Sr. were running the show.

As the founder of Universal Audio, UREI and other successful companies, his studio circuit designs AND recordings as engineer are still among the most highly regarded.
This story is one inspiration I found to build my own studio gear.

Here is some excerpts from the History of Universal Audio:

..."We had gone in to record with Bill, and Bill had everything set up" recalls Murray Allen, then a member of Kenton's band and the man who would one day own
Universal Recording. "Kenton called in to Bill, 'Bill, how's everything in there?' and Bill replied, 'Everything's perfect until the music starts.'"

Thus began an association that would last until Kenton's death. These two mavericks were perfectly suited for each other. For these sessions, Putnam wanted the sound to be as fresh and bold as Kenton's arrangements. So he began to address several aspects that would have profound effects on how records sound.

Putnam devised a band shell for strings that was a mainstay for almost two decades. In addition, he built a drum shed for the isolation of drums to be used for the Kenton recordings. He conducted the first 8-track experiments, which featured a staggered head with a signal-to-noise ratio of 30 dB. But most significantly, perhaps, was the creation of another "home brew": a custom console, complete with rotary faders, 12 inputs, preamps and dedicated echo sends....

....Putnam, who had been recently divorced from his first wife, was suddenly in sync on every level of his new West Coast life. Demonstrating how a recording facility could be built and run, he'd gone head-to-head with Radio Recorders, the biggest independent studio in Los Angeles, and won. He finally found a woman who "understood what my business was about and what I was about." (They married and produced two children, Bill Jr. and Jim, both of whom would continue the Universal brand to the present day.) And, he was making cool records. Examples of Putnam and Sinatra collaborations at United/Western include Sinatra: Basie and Sinatra & Strings. They're textbooks on how strings, horns, brass, rhythm and vocal should be laid down....

...Talk about shrewd. In the early '60s, stereo was roughly at the same evolutionary spot where 5.1 is today. Label owners finally got hip to marketing and releasing stereo product, except that they had none. Or did they? Like Swedien, Ramone and Tom Dowd, Putnam had surreptitiously been running simultaneous stereo mixes along with the expected mono masters for a couple of years. When the labels got wind of this, they offered to pay for the tape. No dice, said Putnam. "However, I will let you pay me for the studio time."...

For more on Bill Putnam Sr. and the history of Universal Audio, check out these links:
Bill Putnam Story 1
Bill Putnam Story 2

Monday, February 16, 2009

12A*7 Vacuum Tubes



I've been compiling a list of the different dual triode 12A*7 preamp tubes and the different versions for use for pro-audio equipment: specifically for mics, micpres and compressors. Of course I screw around with occasional guitar amp as well...
Since 1947, with the introduction of the 12AX7 vacuum tube, there have been lots of interesting variations that can be tried in tube preamp circuits. This list is by no means complete but will provide some quality alternatives to the "Sovtek, Ruby or EH" tube choice that guitar center has.
Most of the below tube types spec close enough to be drop-in replacements (with circuit specification, a certain Mu value tube will be more in focus than other Mu value tubes) but a quick looks at the data sheets is always a good idea for specific biasing, etc..:

Tube Types
Gain (mu) 19
12au7
ECC82
E82CC
ECC802S
5814A
6189
13D5 (brimar)
CV4003 (Mullard)
M8136 (Mullard)

Gain (mu) 41
12av7

Gain (mu) 45
12ay7
6072
7062 (48)
5965 (48)

Gain (mu) 60
12at7
CV455
CV4024
ECC81
6201
E180CC
E81CC
ECC801S

Gain (mu) 70
5751

Gain (mu) 100
12ax7
12ax7a
12ax7WA
12ad7
12dt7
12df7
7025
7729
ECC83
ECC803S
E83CC
CV4004

Some of my favorite are the cleartop Black plate RCA's, Telefunken, Amperex (especially the PQ series), Mullard, GE 5-star, and NOS JAN (joint army/navy- military spec) tubes will be of significant quality. Brimar is still a sleeper...

Sunday, February 15, 2009

Audio Erratum Vol.1 Pt.1 - The Dual La2a




This is an interesting project: a remake of the Teletronix La2a tube opto compressor...in stereo.
Board design is courtesy of [Silent:Arts] via the ProdigyPro forum. Many thanks to the Prodigy community for this one!

I decided to give my version a little taste of the original Teletronix La2a by using UTC A-10 and A-24 transformers. I'm still looking into original T4Bs but, for now, have a pair of clones done by DripElectronics. In my opinion, transformer Lams will have more of an effect on the sonics than the opto circuit anyways.

So far (with no test for power up as of yet) I have the PCB populated, power toroidal, power wiring, all front panel switches and pots and right channel audio wired.
Left to do is left channel audio, meters, power indicator lamp and get some nice tubes!
Here's a sourcing tip: find parts from the Ham radio crowd as opposed to broadcast or pro-audio people: way better deals.

Something to consider: these things have TONS of gain, use a 12AT7 or 12AY7 in the first stage as opposed to the higher gain 12AX7/ECC83.
Variants of the 12AT7 include the Amperex PQ 7062 series (a pin to pin replacement for a 12AT7) which I am looking for now. 5-star 6201's are also worth checking out. Any NOS GE 5-star is good by me as are Telefunken tubes.

I've been putting this together piece by piece over a matter of many months due to the expensive nature of quality parts. Still need to get: one set of UTCs, meters and tubes. Pretty much all the parts that give the comp soul...besides the circuit design of course.
Hopefully it will be finished soon, I have vocals to squash!