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Author Topic: How to get that 40’s sound?  (Read 7395 times)
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WA2SQQ
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« on: January 14, 2018, 08:10:30 PM »

So during the holidays I heard a lot of the old radio programs, like Crosby and Sinatra. All of those recordings had the same unique sound, mostly mid range. I’m wondering if it was the ribbon mics or the sound recording (wire recorders?) they used? I’d like to get that 40’s sound on the air. Any suggestions?
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N1BCG
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« Reply #1 on: January 14, 2018, 10:17:58 PM »

You can certainly equalize your audio however you like within the limits of the transmitter. Whatever you decide on, you're not going to hear it, but everyone else will.
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KD6VXI
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« Reply #2 on: January 14, 2018, 11:05:46 PM »

I have a plug in (vst) that accomplishes this very thing.

It's by Izotope.  I can look it up if you are interested.  I use the same plug in, but have the talk radio preset in use.

--Shane
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WB4AIO
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« Reply #3 on: January 15, 2018, 12:43:56 PM »

So during the holidays I heard a lot of the old radio programs, like Crosby and Sinatra. All of those recordings had the same unique sound, mostly mid range. I’m wondering if it was the ribbon mics or the sound recording (wire recorders?) they used? I’d like to get that 40’s sound on the air. Any suggestions?

I wasn't around in the 40s, but my work in broadcasting in the 70s had me using some of this old gear from time to time, and talking to people who had. In those days, broadcast microphones and preamps were already very high fidelity, comparable to what we have now (though with the distinctive sound of vacuum tubes).

Ribbon mikes were the most common, so start by using one. The old 1960s "Reslo" brand ribbon microphones have a great sound, but are much, much cheaper on the used market than the more famous RCA ribbons.

Ribbons had very slight extreme high end rolloff, middling transient response, and a lot of proximity bass boost effect -- though most commonly they were placed a foot or more distant from the performers to alleviate the latter, in very quiet and echo-free (through padding or acoustic treatments on the floors and walls) rooms. This gave them a very smooth and detailed midrange, unsmeared by reflections. That midrange was often emphasized by later processing such as transmitter or disk lathe peak limiters -- not because of any equalization, but just because lower-level details were brought out. Some of the ribbon mics had a "voice" setting, too, which rolled off gently below 200 Hz or so, while still allowing response down to 30 or 40 Hz to come through -- a totally different sound than a high pass filter that eliminates the low bass.

The processing used was almost always transformer-coupled peak limiters or compressors, tube types of course. These probably contributed a lot to the sound you're seeking. Building something based on an old RCA BA-6 compressor, or GE Unilevel, or the old Armed Forces Radio AM-864/U peak limiter would capture that sound, I think.

73,

Kevin.
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VE3ELQ
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« Reply #4 on: January 15, 2018, 02:55:58 PM »

There is some good info on the old stuff on the site linked below including details of the Fairchild 670. Interesting how it can now be done on a credit card size PCB with some op amps and a 9V battery.

73s Nigel

https://www.historyofrecording.com/fairchild670.html
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Jim, W5JO
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« Reply #5 on: January 15, 2018, 03:59:10 PM »

If you want to hear that sound at your QTH, get a SX-42 with the reproducer speaker.  I just finished restoring one and it reminds me of the sound of radio in the late 40s and 50s.  Yes, I am that old.
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WD4DMZ
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« Reply #6 on: January 15, 2018, 05:19:06 PM »

Agree on the SX42 and bass reflex reproducer. I also have the SX62 and reproducer in my shack. When on AM I'll often use the SX42, as I did this morning, for the receiver. The audio quality of the AM transmissions really comes through. Both will extend into the FM broadcast band. Not stereo but still very good.

My son even notes just how good the FM sound is.

Unfortunately, the D104 I usually use on the Viking 2 does not compare to some of the audio I hear on the bands. Someday I need to acquire an old ribbon mic but the prices they command is discouraging.

Rich
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WA2SQQ
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« Reply #7 on: January 15, 2018, 07:07:24 PM »

I got lots of reading - thanks
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WBear2GCR
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« Reply #8 on: January 17, 2018, 04:58:39 PM »


The 40's sound?

It was a combination of the technology.

Essentially band limited, high 2nd & 3rd harmonic and low (nil) higher order harmonics.

You can get that today by using transformers, wax & paper caps, carbon comp resistors, tubes, (of course), best to use
DHT (Directly Heated Triodes), speakers with field coils and paper cones, no tweeters, no super low bass.

Essentially you can just buy and repair an old floor standing console radio from the late 1940s, and pipe in a
modern source. It's been done, and at least someone I've seen on the web sells just this trick, but with either
a bluetooth interface or a USB (MP3 usually) input added on...



* PHILCO 1941.JPG (662.26 KB, 1587x1600 - viewed 198 times.)
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WZ8J
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« Reply #9 on: January 19, 2018, 10:02:59 AM »

Just use a stock Valiant...oops sorry, that's 1920's sound  Grin
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W3NE
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« Reply #10 on: January 19, 2018, 12:35:15 PM »

The quest for '40s sound is interesting. I was there then, and believe me, we did not think it was so wonderful! There was always an effort to produce better quality but severe limitations were introduced by even the best disc recording lathes, schellac 78 rpm pressings and speaker quality (among other things in the chain). Wire recorders were not used for broadcast audio because of their horrendously poor quality except for rare field pickups. Networks' major music and drama originations were pretty good, although often distributed over 5 kc. lines lines to affiliates. Late at night big bands picked up from remote venues like hotels and ballrooms also suffered from narrow bandwidth transmission lines and selective fading of RF transmissions. Fortunately, many local stations had their own studio bands (WFIL, WIP and WCAU in Philadelphia), who played two or three times during the day, and their quality was excellent. Schellac record pressings of the time, however, produced distortion and had rapid groove wear due to tracing error toward the center of the record but they had reasonable quality at their outer edges -- until wear from use increased surface noise! The best commercial 78 rpm discs, before CBS introduced the LP, were ffRR recordings from England ca. 1948 but there were no domestic recordings to match them.

It was not until after the war, when a "liberated" German Magnetophone was brought to the U.S. that our engineers caught on to tape recording but even then there was a learning curve to be conquered before broadcast quality machines were produced. Compounding all of this in AM broadcast was continued use of transmission lines of marginal (5 kc.) quality; a treat was when a program was transferred over an 8kc. line!

Restoration of old record quality by computer analysis is what has saved those old recordings and made them listenable again today. Noise reduction and elimintion of pops and scratches have enabled re-release of most old disc recordings that in a sense, are better than the originals.

I am not personally interested in going back 75 years but that doesn't matter because now I can't hear anything above 6 kc anyway. It is definitely reassuring, though, to know there are still some who appreciate -- and want to emulate -- entertainment from back then. Good luck with your experiments!

Bob - NE
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N1BCG
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« Reply #11 on: January 19, 2018, 01:56:47 PM »

What a fascinating lesson in recording and broadcast history!
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W3NE
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« Reply #12 on: January 20, 2018, 03:36:57 PM »

One of the best chronologies of audio developments in the U.S. is Audio Engineering magazine. It was an outgrowth of that terrific West Coast ham magazine Radio (which exceeded the value of QST in many respects), and attracted technical articles by many of the luminaries in audio technology of the time. It is available on-line at:
http://www.americanradiohistory.com/Audio-Magazine.htm

Bob - NE

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WB5IRI
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« Reply #13 on: January 22, 2018, 04:04:28 PM »

Unfortunately, the D104 I usually use on the Viking 2 does not compare to some of the audio I hear on the bands. Someday I need to acquire an old ribbon mic but the prices they command is discouraging.

Rich

There are inexpensive ribbon mics out there that sound quite good, especially if you are going to use them for voice communication rather than high end studio recording: http://recordinghacks.com/2008/11/01/chinese-ribbon-microphone-designs/

In addition, if you have an old microphone with enough room inside (NOT a D104!) that needs reworking, Michael Farabee of RestoMod Mics, http://restomodmics.com/, will custom build a ribbon element for you. He put one in an old Astatic 77 for me, and it sounds great -- I use it for amateur radio, of course, but also for studio work -- beautiful in both application, warm, mellow sound. Like I said, you have to have a mic head large enough for the element -- check with him first about suitability.

And finally, you want to use a pop filter with a ribbon mic, and never, ever blow into a ribbon to "test" it. That can actually tear the ribbon, thus ruining the element. Don't drop one, either -- they are wonderful devices, and fascinating the way they work, but they are fragile and take reasonable care.

Doug
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WD4DMZ
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« Reply #14 on: January 22, 2018, 04:24:50 PM »

Good info. Thanks.

Rich
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WB5IRI
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« Reply #15 on: January 23, 2018, 10:48:56 AM »

Restomod Mics test recording of the Astatic 77 they did for me: https://www.youtube.com/watch?v=kBrSPuNcVHs
A really great job.
Doug
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WA2SQQ
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« Reply #16 on: January 23, 2018, 04:36:58 PM »

Heard about this place. How are they prices?
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WB5IRI
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« Reply #17 on: January 24, 2018, 05:14:20 PM »

Reasonable, I think. Depends on what you want him to do. My ribbon element installation in the Astatic 77 shell (remember, Mike built the element himself) was $165. That was in 2014. If you are going for a full restore of an antique mic to original specs, then it might be more. Give him a call, 912-265-2872, tell him what you want to do, and he'll give you a quote. The man does good work. He also sells microphones out of his stock, both new and rebuilt. Last email I have for him is michaelfarabeeproductions@yahoo.com .
Doug
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