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PostPosted: Sat Dec 13, 2008 4:46 am
by soundbrigade
I could specify the subject better but this can allow for various discussions on the matter of "stone cakes" as 78rpm records are called in Swedish.
A friend asked me about a simple correcting amp for his heap of old records. When I looked at the graphs I noticed that they looked very much like a RIAA-curve but without the drop in frequency above 1kHz (the curve went horistontal).
I have started to look at the various projects that can be found in Audio Anthology.

PostPosted: Sat Dec 13, 2008 4:09 pm
by Shannon Parks
I bet both John Broskie at Tube Cad Journal and Jim Hagerman at Hagtech have useful info on their websites regarding the non-RIAA eq methods. Just was looking at some of the oddball ones recently but I forget where at at. Yellow_Light_Colorz_PDT_14

Groove Grinders and Stone Cakes

PostPosted: Tue Dec 16, 2008 9:16 am
by EWBrown
A lot of those 78s had some weird, or even, none, equilazation, these go back to the purely mechanical "Victrola" days with wind-up turntables, and the big "flower" horn, and those wonderful steel spikes or cactus spine needles vibrating the thin diaphragm, whch the "horn" then (sort of) amplified, with a frequency response between 200 Hz and 3 KHz, most likely.Most of that would be covered up by the frictional noise, anyway...

schrch, schrch, schrch.......

Use of a decent modern cartridge and stylus on a "stone cake" would probably present a serious hazard to the stylus's well being... :o

"Stone Cakes", I like that Yellow_Light_Colorz_PDT_04 Yellow_Light_Colorz_PDT_03 Perfect description for those things.

Then there were the 16 RPM records, usualy recorded speech, rather than music, as the frequency response wouldn't reach too high, maybe OK for the Warsaw All-Tuba Polka and Marching Band, perhaps Yellow_Light_Colorz_PDT_04

I have some glass 16 RPMs of an economics lecture at Harvard University, made back in the late 1930s or 1940s, the weird part is that they start in the center and work out towards the edge. Truly riveting listening.... Yellow_Light_Colorz_PDT_50 Yellow_Light_Colorz_PDT_26 Yellow_Light_Colorz_PDT_27 Yellow_Light_Colorz_PDT_22

Then there were the smaller diameter yellow plastic "kid's music" 78s which usually wore out about the same time that the heavy tracking steel "dart" needle did. :o

/ed B

PostPosted: Tue Feb 24, 2009 1:06 pm
by dhuebert
From my reading, I understand that for most of the lifespan of 78 Steinkaaken there were really no industry wide standards for either recording speed or EQ. A couple of years ago I started collecting 78s and recording them onto my Mac. Every one of them required different EQing and gain. I wouldn't worry about trying to build a tone shaped amp for them, but rather record them into your computer and use the tools there or build an amp with a good tone stack to modify for each record.


PostPosted: Tue Feb 24, 2009 11:11 pm
by nyazzip
there is a thrift shop about a mile away from me that is full of moldy old '78s...i have nothing to play them on so i never consider they are mostly "classical/orchestral/chamber" type music which ain't my cuppa.
a month ago at the same place they had some monster '60s zenith console desk-radio there, and damned if i couldn't tell if it was tube or solid state. it was too dark to peer through the perf-grating in back. i suspected it was tube, because it didn't advertise "solid state" anywhere, and it was from the early '60s.
i went back the next week with a flashlight in my pocket to look and it was gone

PostPosted: Wed Feb 25, 2009 6:21 am
by EWBrown
Early '60s, most likely tubes. Solid State power was still in its infancy, and the quality was generally abysmal at best...

It was OK for those ubiquitous "six transistor" pocket radios, and some AM car radios, which in that era, used space charge tubes which then drove a large germanium transistor in a Class A SET (Single Ended Transistor) output stage, capable of about 2 watts out. This eliminated the HV supply, transformer and vibrator of inverter, so everything could run off the 12V battery voltage.

When Solid State finally hit the market big time, the manufacturers generally bragged about it, and made it abundantly clear that "tubes were dead" in their opinions Yellow_Light_Colorz_PDT_09 :o Yellow_Light_Colorz_PDT_21

The claimed quantity of transistors was always a bragging feature, and those "14 transistor" radios were still basically six functional transistors, and the remaining 8 transistors were simply used as diodes.
Cheap marketing hype of the day Yellow_Light_Colorz_PDT_09 Yellow_Light_Colorz_PDT_04

/ed B

PostPosted: Mon Mar 02, 2009 7:33 pm
by Ty_Bower
How would I know a 78 when I saw one? I've got about forty of these "albums", with each album containing anywhere from three to eight platters each. The things are about twice as thick as a regular LP, very heavy, and seem to have no flex at all. They don't seem to indicate any playback speed on them anywhere, and it looks like each side has only one track. Are these 78s?

Image Image Image

PostPosted: Mon Mar 02, 2009 8:22 pm
by TomMcNally
Are they 10" as opposed to 12" ?
78's were almost always 10" ...

They look like 78's.

ahhhh ... play them and see ?

PostPosted: Mon Mar 02, 2009 8:31 pm
by Geek
Ty_Bower wrote:How would I know a 78 when I saw one?

Groove width. They are wider.

Something we all forgot about until now... 78's have a much larger groove. A 33/45 stylus will destroy (by cutting into) a 78. A 78 stylus is required.


PostPosted: Tue Mar 03, 2009 8:39 pm
by dhuebert
78's can be alot of fun to collect. What you find tells a story of musical tastes in the past. I imagine that no matter where you are in North America you will find the likes of Bing Crosby and Elvis but there were some local stars as well as big stars who didn't appeal to some demographics too. Where I live, I can find lots of Don Messer, ever heard of him? An important Canadian. On the other hand I have seen no blues at all except for some big band stuff. Interestingly (or maybe not) there was a big craze hereabouts for Boogie Woogie. I have a beautiful complete set of Pete Johnson and Albert Ammons "8 To The Bar". I have never yet seen a Ray Charles! (boo hoo)

Anyone heard of Spade Cooley? King of country swing until he got drunk one night...

Alvino Ray?

The Girls of the Golden West?

Hank Snow, another important Canadian. Some times "The Yodeling Ranger" sometimes "The Singing Ranger"

What about Gale Storm? Had her own TV show. Why Do Fools Fall in Love and all that.

Wonderful stuff.

Etc, etc


PostPosted: Tue Mar 03, 2009 8:41 pm
by dhuebert
Post 497

PostPosted: Tue Mar 03, 2009 8:41 pm
by dhuebert
post 498

PostPosted: Tue Mar 03, 2009 8:42 pm
by dhuebert
Post 499

497, 498, 499....

PostPosted: Wed Mar 04, 2009 7:27 am
by EWBrown
Hey, that's cheating Yellow_Light_Colorz_PDT_08 Yellow_Light_Colorz_PDT_04 :o

/ed B

PostPosted: Wed Mar 04, 2009 9:03 am
by lynxx
Let him have some fun Ed. I have a longer way to go than he did??!!! Yellow_Light_Colorz_PDT_05