Recording 78 rpm records at 33 or 45 rpm

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rec78
Posts: 15
Joined: Thu Dec 24, 2009 3:14 am

Recording 78 rpm records at 33 or 45 rpm

Post by rec78 »

Hello, First of all I am a registered user for about 2 months and I love this software. I am have a lot of fun with it. I purchased Goldwave because I have many (5000-6000) 78 rpm records and plan to buy more if I find them at the right prices. A lot of times I get them for free. A lot of them should have been thrown away many years ago.but you know how it is when you collect stuff-somehow you just can't let go. Well I am glad i kept all of them now, because even if they just have one more play left (no matter how bad it is)-Goldwave can usually rescue it. After I record them and save them to the internet archives and CD's, I give them away. (the 78's not the CD's)
The following I have learned mostly through trial and error. The reasons for recording 78's at lower speeds is because most of the modern record players do not have the 78 speed on them. You can also record slightly warped 78's that no longer can be played at 78rpm, BUT may still be playable at lower speeds. (I have many of these).
Here is what I do:
First i set the record volume at 70 % but with 78's this can vary greatly -- most of the later 78's(those recorded in the 1950's should probably be recorded around 40 %). Some of the very early ones 1900-1910 era may have to be recorded at 100 % volume. My records are mostly from the 1910's thru the 1930's and 70 % recording volume works fine for most but again some have to be recorded at different volume levels.

1. Click on the new button- Set the number of channels to (2 stereo)
Sampling rate ( 44100 )
Initial length (10:00) I have never seen a 78rpm record last more than 10 minutes even when recorded at 33 rpm. Click Ok (These settings will stay the same so if you do a bunch in a row you just have to click OK).(However this initial setting does not matter because it will just keep recording even if longer than 10 minutes)
2. Record the phonograph record.
3. The first thing I do after the record is recorded is use the Time warp. I have added a pre-set of 234.8 for 78's recorded at 33 rpm ( using direct mathematics 78.26/33.33=234.8 for 33 rpm) and 174.8 for records recorded at 45 rpm (78.26/44.77 =174.8 for 45 rpm) I do not know if any other algorithm or number should be used the the above numbers work just fine for me.
4. I now just click the pop/click and use the default setting ( just click the OK button)
5. Now i do the noise reduction (usually on the default setting-this can be trickier and take some patience-sometimes you have to move the cues but usually the default setting works great.
6.Volume -again usually the default setting works fine-but sometimes you may need some adjustments as 78 rpm records recorded before 1950 were not recorded at standardized volume levels.
I have set the order of buttons from the lower right to left: 1.time warp 2.pop/click 3. noise reduction 4. volume (these are basically all i need. I like to leave a lead-in of silence of 1-2 seconds( I just zero out all the early noises with the max volume control) also i found that when i send the recordings to the internet archives it is best to use 3-4 seconds silence at the end of the recording - seems that sometimes the archives does not play the last few seconds).

Despite all of this there are still some records I recorded that i cannot seem to get the grinding noises out of no matter what I do. If anyone has any suggestions I would greatly appreciate them. And thanks in advance.

Summary for recording 78rpm records at 33 or 45rpm:
1.Click new-set parameters-click OK
2. Record
3. Time warp
4. pop/click
5. noise reduction
6. volume
7. any other editing.
I hope this helps someone-I wrote it because i could not find any information like this on the internet or in the instructions. Also I would appreciate any suggestions to help me make better recordings. By the way-did I say that I love this product? Thanks, Bob

JackH
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by JackH »

Sounds like you've developed a pretty good system! One problem though is you're not really getting the equalization right this way. I assume that your phono preamp is applying eq (if not, you can ignore all of this!), but it's doing so to the slowed-down record. This means that all the frequencies have been shifted downward when the eq is applied, which applies the eq to the wrong frequencies. Here are two steps I recommend adding to your procedure:

2.5. Apply the "Inverse RIAA curve" preset in GW's spectrum filter.

3.5. Apply the"RIAA equalization curve" in GW's spectrum filter.

This should give you the sound as intended, and will probably reduce the surface noise, since it will place the treble cut at a lower point, below where a lot of the noise will be.

BTW, this assumes that your records are mastered with RIAA equalization. This became standard in the '50s; older records used various different eq curves, which also can be done in the spectrum filter, though I don't believe there are any presets for them.

Another thing I'd definitely do is mix the recording to mono at some point, if you're using a stereo catridge. This alone will eliminate a lot of surface noise.

I know this can be a lot of fun... I did my 78 recording setup a few years ago. I tried the speed shift trick similar to yours, then ended up modifying an old turntable to run at 78. I had treated myself to a new turntable and needed a use for the old one! It was actually quite easy, and required changing only one resistor in the speed control circuit. I got a cartridge designed for 78s, which helped the quality also. I then went all-out, and bulit a phono preamp from plans I found on the internet. That was enough to keep me occupied for quite a while, to borrow a quote from the late Don Adams "And, loving it!"

donrandall
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by donrandall »

I am always interested in seeing how many different people find so many different ways to use Goldwave. You guys ROCK!

DewDude420
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DewDude420 »

It's great to see someone do the math required to convert 33/45 to 78.

This interests me very much because, as many people on this forum may have figured out. I've spent a great deal of time honing my skills in digital audio so I can preserve and restore the analog. I also got in to vinyl because of the sound quality improvement...the nice warm analog. However, in the process I found I really had to learn the format I'm going from...knowing a lot about the format I'm going from just made things better...and well, it answered a lot of those odd questions I had.

I've done a lot of vinyl. I thought I knew a lot about vinyl, but it's been only recently that I got so deep in to it that I realized...I knew nothing about it. I never knew there was a complex setup procedure required with overhang and vertical height and tracking force because a lot of the tables i owned in the past were cheap models that had no adjustments, or were a T4P system that was designed to eliminate all of those complicated setups. When I got a table that took a standard mount cartridge, I had no idea how complicated the stuff was, and most of the time I wound up with a horrible sounding misaligned cart. There's only maybe one or two LP's I did on that table that I was able to get anything decent sounding out of, even new vinyl sounded bad. Then I learned about all that lovely stuff...smacked myself in the face....and bought a linear tracking table with a tangential arm. I'm waiting for delivery of a brand new grado green cart for it so i can really start goin to town. I've wanted to get in to 78 transfers...but I can't modify my table to do 78...well, it might be possible...but if it is...i am NOT attempting it, this table is entirely too complex of a machine for me to even want to attempt to take it apart...plus it's the most expensive piece of audio gear I own. So...I've given serious thought to transfering 78's at 45rpm and adjusting speed, just never figured out how to put the math together.

First of all, I don't really find much wrong with your current method. The one thing I might try doing is running a pop/click BEFORE you run time-warp...since some of the popping/scratching you'll get will be at "33/45" speed. What I mean is even though the record is recorded at 78rpm, and yes, some of the scratches will only be "scratches" at 78rpm speed..there's also likely some additional crackling and noise that, when sped up, well...they might not show up after the speed up...and you might not hear them...they might not even affect the final waveform...but as someone who's dedicated to keeping the waveform as clean as possible. Honestly, I've NEVER had the chance to play with 78 audio that hasn't somehow already been modified..so I can't really say what would work best. (On a side note, if you'd be willing to send me a FLAC of some straight 78 transfers to play with, I could make not only better comments on the process to help you, but figure out the best way to tackle audio like that. Most of what I've been given to play with is so horrible there is no hope for it).

As far as volume. The first thing I will tell you is 24-bit is your friend! I'm not just talking about the floating point percision done in goldwave, but if you record in 24-bit, the amount of resolution you have for lower amplitudes means you don't have to worry about having any audio you'd want to keep dangerously close to the extreme low end. Therefore, you could record with even an extremely low amplitude and safely bring it up. 16-bit's lower end is -96dbFS, 24-bit's lower end is -120dbFS...it's approximately the same dynamic range of human hearing. Mind you, I don't get anymore technical than that. I know how dB relates to amplifier output..and speaker efficiency..but it can get pretty complex when it comes to just where on the scale 0dbFS is (because it, itself, is a relative term to where a digital-to-analog converter will clip). With that being said...the more you have...the better, so you don't have to worry as much if should say...one 78 records peaking at -6 and another one only peaks at -24....if recorded at 24-bit, you can boost the levels after recording without losing anything...to be honest, i've never played around with 16-bit to see just at what level in an analog recording would this happen. Most of what I can do is look at the early analog-to-digital transfers for CD's that were done in an era before digital post-processing was very uncommon...and 0dB on analog masters were genrally calibrated to be somewhere around -18 or -15dbFS...a far far quieter cry from todays modern CD's which are so hot they tend look almost like a solid brick in an overall envelope view in goldwave. So I'd find a good level for a more modern cut 78 and then not touch that level..leaving older 78's recording at level. the amount of noise you'll bring in changing the recording volume will increase...and to be honest...if a 78 is THAT noisy...nothing is going to matter.

That's the other thing...a quick-n-dirty-n-long thing about 78's...going on the assumption you might know a little and I for some reason feel I know more...however, since you asked about the grinding noise...that started a chain in my head while i was typing the rest up (actually, i did take breaks to check out the TV).

The thing to remember about 78's, especially OLD 78's....is the technology. Electric recording methods weren't around till the 20's....so it's pretty safe to assume that most discs prior to maybe even 1930 are acoustically recorded. This resulted in I'm sure a pretty low mixed fidelity...and might explain some of the grinding noise. The more probable cause of the grinding noise...especially if it exists on later discs...is that they were played on a victrola or some very old player a few times..or a lot..or maybe even once. they were also made of shellac...which is a brittle substance and seems like it would scratch pretty easily when that steel needle runs in the groove. You might not notice it on a virctrola because of the lousy frequency response..but you would with modern pickups. Another issue...unless you're using a 78 stylus....you're going to get bad sound. 78's used a larger groove..and there is still some 78's being cut...but my source tells me they CAN put microgroove on 78...and do stereo (which he's sending me soon)...but that generally they're cutting mono old groove width for reproduction purposes. Since both the 33 and 45 use the same size groove, much smaller than the 78...the needle not only barely fits in the groove...but sits really low, and if you're using an elliptical or some more exotic finer cut diamond...you're likely touching less of the groove wall and getting a lot of the very bottom of the groove...which is likely really worn out. If you use the poper stylus, you'll contact the proper area of the groove wall...i'm not sure if you are..you didn't mention it.

As JackH tried to explain...RIAA mastering wasn't done till the 50's..and I have some very early 33's that are non-equalized at all. Different labels had different curves for mastering...which might explain why some record companies sold players...either way...RIAA is either too strong or just plain wrong. I used to have a chart that went to a preamp that had all the various known (at the time) EQ curves and what settings you needed to use. It was designed as both a phono preamp and tape-head preamp...so it had all kinds of stuff. At the time it seemed (at least to me) like a goldmine for possible starting points for various EQ's, and if I find it..i'll send it to you. If you knew the actual curve...then ideally you should run the inverse RIAA EQ and then apply the proper one...but..even this is somewhat inaccurate as the digital EQ is more accurate than whatever your preamp uses...so it'll be a good approximation, but not exact.

In reality...the final result depends on you. I tend to EQ my vinyl transfers to, at least what I, think sounds good...I also try to play mastering engineer after doing restoration. So I wouldn't really care a whole lot about how accurate the inital curve is because I'm going to be modifying it later on...so i'd likely adjust out any incorrectness. However...I do personally have that anal-retentive part of me that actually wants to build a purely flat phono preamp and do RIAA digitally becuase I could adjust the curve...but I also have some interesting theories about noise-reduction and such.

The overall sound quality will also change sometime in the 40's when magnetic recording media started becoming in use and things moved away from electric direct-to-disc transcriptions...but that doesn't mean a 78 cut in the early 50's wasn't at some point abused and mistreated. I'd be surprised (and up to the challenge) to see if one could get anything from a 78 from the teens.

Oh...and on how long a 78 is time wise...it was generally considered that the standard 10 inch gave 3 minutes of audio..maybe 3 and a half...going to 12 inches only took it up to 4...5 max. Most classical in the era was issued on 12 inch, where popular music continued to be issued in 10.

rec78
Posts: 15
Joined: Thu Dec 24, 2009 3:14 am

Re: Recording 78 rpm records at 33 or 45 rpm

Post by rec78 »

Wow ! many thanks Jack H and Jay Moore for the responses !! Thanks, Don also!

I have modified the system as follows per your advice and it does make better sounding recordings!

Summary for recording 78rpm records at 33 or 45rpm:

1.Click new-set parameters-click OK
2. Record
2.5 Apply the "Inverse RIAA curve" preset in GW's spectrum filter
3. Time warp
3.5. Apply the"RIAA equalization curve" in GW's spectrum filter.
4. pop/click
4.5 use the channel mix and mix to mono mix
5. noise reduction
6. volume
7. any other editing.

I do not know if this is the proper sequence for best results but it seems to work fairly well. I will try other configurations. I don't know if putting the mono mix where i put it is the correct place for it. Jay-you suggested putting the pop/click before the time warp-should i put it before or after applying the inverse RIAA curve? I guess i could just experiment but i will welcome any suggestions and try them out. Thanks again ! Bob

Jay, most of my records are from the 1910-1938 time frame. Most of the columbia blue labels and victor black labels record well. The ones that record the best (at least in my limited experience) are the columbia black labels. I don't know much, if anything, about RIAA curves - I just try to follow your instructions. Electric recordings were started in 1925 by Columbia with other companies soon following suit.However they still made acoustic records on their cheaper labels until 1929. I like acoustic records.
I used to use an old school record player when i started and now have a new audio-technicha that works great. I use a stereo 3-mil needle.(yes there are 3mil needles around) I got this needle because a lot of my records are very worn and i figured it would play them better than a 2.5 or 2.8 mil needle.( I don't know if it does but i am very happy with it.)
Jay-I don't know how to record and send a FLAC file. There is a set for 24 bit on the goldwave but i haven't figured out how to use it yet. - Bob

DewDude420
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DewDude420 »

I don't know much about how blue or black labels were recorded. However, the one thing I do know is in that time frame...each record label did thier own thing...so the levels being different label to label, even record to record, is normal. Each recording engineer (because remember, a lot of things were still trial-and-error and far from a science back then) had their own idea of how to cut the record. Nothing was standardized...not even speed till synchronous motors came in to play.

As far as RIAA curves..let me see if I can explain it. Originally, records were cut full bandwidth to a disc. This worked...to a degree...however, the fidelity still lacked. They discovered that if they EQ'd the audio BEFORE cutting it to the disc...and applied an "inverse" EQ of the same curve during playback, they could actually increase the fidelity of the record...but you had to have this playback EQ pretty close. In the old days, each company, as i stated, had their own standard. In the 50's the RIAA stepped in and set a standard playback EQ that was to be used by all record labels. This was back when the RIAA was more about setting standards than suing people.

In an RIAA EQ, and most of them....the bass and treble are adjusted...usually the bass is cut about 10db or more when the record is cut and the high-end is boosted about 12db or so. This reduces the amount of space a groove takes up since the bass modulation isn't making the thing larger...and it also preserves more of the high-frequencies. It wound up just being a good thing..and it's actually the basis of "mastering". Granted today, mastering is an important part...the original job of a mastering engineer was to take the original source and cut records. This grew in to a science and artform over the years as people learned more about it.

Now, my point on RIAA..is not to get too hung up on it. The worst that's going to happen is your low end is going to be REALLY boosted and the top-end will be reduced..and, to be honest, you should be adjusting the EQ levels to how YOU like them...not how a curve says it should be.

Not to put down Jack's suggestion, but steps 2.5 and 3.5 are useless and redundant. There is no real reason one needs to inverse before speed warp just to reapply it again. I can't see the logic. Better logic would include JUST the inverse curve without the second curve....but the first is kind of...redundant. You should worry about doing a final EQ to make it sound how you want it rather than getting hung up n curves if you don't understand them fully.

If you don't know how to do anything witha FLAC file....that's fine. I thought maybe you did. FLAC is mostly just a lossless compression. It's optimized to compress PCM audio down to something a bit smaller without modifying the audio itself. 24-bit actually is more than just a setting in goldwave, you need to have special hardware to record in 24-bit to begin with. It's a nice idea if you've got it, however, I don't think it'll be a requirement.

The biggest thing is to experiment. Keep copies of the raw transfers around so you don't trash those. I'm sure you figured out it's not something you get the hang of overnight...and can take YEARS to get good.

I do believe you have a 3mil stereo needle...becuase I've seen them. Most acoustically cut 78s had grooves up to 4 or 5 mil wide...but MOST electrically cut 78's had a 3 mil groove width. However, while using too small a stylus is a problem, using to large a stylus can ALSO cause excessive noise. The point is to get the stylus to ride either above or below the older main wear points...where there's better audio. This is one of the reasons elliptical cut styli sound better on microgroove stereo than spherical/conical styli...it rides lower in the groove and contacts more of the unharmed groovewall.

http://www.auldworks.com/articles/dtrans2.htm is a great little page you should read. Most everything I want to cover is already there...it's an EXCELLENT primer for anyone doing anything with 78's. It discusses in more detail things like groove width...and why you should and shouldn't do this or that. A highly recommended read. I will tell you if you read the part about vertical cut discs...when it mentions about how to wire a cartridge properly...you don't really need to do that. Basically what it's telling you to do is invert a channel before summing it to mono. Stereo LP's use the 45/45 method actually invented by EMI in 1935...each side of the groove wall, cut at 45 degrees is each channel. When you play a mono lateral cut LP, as the majority from that era are...it works out...and I can't remember exactly how...provided your overhang is set up right...if not then you get a slight time difference in the channels....and to the same extent, you CAN play a vertical cut LP with a standard cartridge....it's just the channels will be out of phase....but easier to fix digitally than rewire your turntable.

Gord
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by Gord »

>There is no real reason one needs to inverse before speed warp
>just to reapply it again. I can't see the logic.

Those additional steps make sense, at least in theory. If RIAA-like recording EQ was applied to the original recording it was presumably applied at normal speed. Playing back at a lower speed shifts the entire frequency spectrum downward (the opposite of the "chipmunk effect") so when playing back at that speed the playback EQ was effectively applied to a different set of frequencies in the original recording: high-end frequencies that would have been EQ'd when played back at normal speed could get missed if they are below the cutoff when played back at the slower speed. The EQ before the time warp will undo that, then the EQ after will apply the playback EQ to the frequencies that would have been affected if the record had been played back at normal speed.

>Better logic would include JUST the inverse curve without the
>second curve....but the first is kind of...redundant. You should
>worry about doing a final EQ to make it sound how you want it

I have taken the opposite approach when converting my vinyl. I don't presume to have better ears than the professional producers, sound engineers, and masterers (?) who created the recording in the first place. I just try to make my digital copy as close to the original as I can. My personal EQ preferences (or compensation for my aging eardrums) can be made at playback time, and in any case those adjustments will depend on the playback equipment and the listening environment.

DewDude420
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DewDude420 »

the biggest problem with all of this lies with the RIAA curve itself.

here's something people don't realize...just becuase you apply a curve digitally...DOES NOT MEAN it's going to be 100% accurate with the analog method. There's a TON of different methods of applying RIAA EQ to the phono signal...different methods have different results. when dealing with analog electronic components no two components are EXACTLY alike...there is always variances between units as far as EQ goes. sure..it's the same basic curve...but the exact values will be different preamp to preamp...so the exact gain and width will vary. Also, there are SEVERAL variances on RIAA curves that have been more or less adopted by various designers and engineers. they're all close enough to be "compatible".

the inverse RIAA curve in Goldwave, for example, does not accurately match what my preamp is...the difference is barely noticable...and i can modify the goldwave EQ to match...but the point is...the standard spec doesn't mean every EQ is going to have the exact same EQ curve....

for the most part, RIAA only affects the low end and top end of the recording...basically even after you speed it up, everything above 500hz is unaffected and everything above 20 will be attenuated. when dealing with 78's, this little bit of shift has no real difference in the recording...the recordings generally don't respond THAT well.

if you really want to get anal on technical quality...then you should do all your restortaion BEFORE apply inverse RIAA and speeding up..i mean, you may need an additional step...but all the low level noise from the preamp...along with the speed and duration of static clicks...will be shifted up....in reality..most 78's are too noisy to notice.

i didn't say it didn't make any logical sense at all.....just not for this application. i mean, there's a difference between being EXACT...and wasting time. the fidelity of most 78's isn't enough to warrent extra RIAA adjusting steps...it's better to just try to adjust that later.

I'm also not talking about applying your personal EQ likeing to the file....no no no. I for one have an EQ curve on my hardware EQ...I spent many many months listening to a lot of stuff until i found the sweet spot. i consider it my reference curve...whenever I master...I'm mastering through my curve till it sounds the way I want to...yes, that sounds kooky....but the idea is if I have a personal EQ curve I'm used to listening to...that the majority of my "reference" recordings sound right in....if it sounds off...then it's in the original source....i can hear mastering differences through my EQ...i don't know about most people...i've been told by quite a few knowledgable people that my ability to use timbre to identify sounds is far far beyond people who have worked at it...

but really...to begin with the EQ on acoustical recordings wasn't always precise...you had what modifications the horn made...and those might not be true-to-life when played electrically.

so, my whole comment about the riaa curve being unnecessary only applied to THIS scenario, like i said, by applying your restortion effects after speed up, you're greatly "damaging the integrity" of the recording by some standards. if the dude's got thousands of LP's to do...then he needs to save as many steps as possible...one final EQ step is less than two.

that's all.

Kummel
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by Kummel »

On 78rpm's, there were no RIAA curve applied, so only the inverse RIAA curve is needed. I try always to verify the real bandwidth of the recorded signal, and in most of the cases the upper limit is at 4 kHz very coarse. That is ^probably because the engineers expected the 78rpm's to be played with mechanical devices, or with electrical devices having about the same bandwith.
So, in most of the cases, I apply a 50-4000 bandpass filter at the end of the process, all the rest beeing distorsion and hiss.
:D

DougDbug
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DougDbug »

Your porcedure looks good.

If I had over 5000 records to digitize, I'd look for a 78RPM turntable. It will save recording time, and it will help to get the equalization right (or at least the EQ will be closer). I wouldn't worry too much about getting the EQ exactly right. There is a good chance that you'll want to adjust the EQ for better sound anyway. A lot of older LPs have weak rolled-off highs, and I often boost the high frequencies. I'm sure the situation is worse with 78's. (Of course with 78's, you can benefit from reducing the highest frequencies where there is only noise.)

As far as recording levels, you can adjust by ear after recording, or you can simply Maximize. I usually run maximize after recording to check for clipping (distortion). If it reports 0dB before maximizing, I assume the file is clipped, and I re-record. I also run maximize after processing and before saving. (GoldWave can temporarily go over 0dB, but most formats will be clipped if you save a file over 0dB.)

You should not need 24-bit recording. 78's and LPs don't have that much dynamic range and most soundcards are 16-bit. Unless you have a professional 24-bit soundcard, you are simply putting 16-bits of data into a 24-bit format, which gains you nothing.

I don't think there is anything you can do about the "grinding" noise. For clicks, ticks & pops I use Wave Repair. It generally works very well, and it has one method where you can cover-up a defect in one channel with the signal from the other channel. This can work well with most stereo records (it's not noticeable if you loose stereo for a few milliseconds), and it works very well with stereo recordins of mono records. The downside to Wave Repair is that it's time-consuming... Too time consuming for 5000 records. See this page for some other (more-automated) click-removal software.

DewDude420
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DewDude420 »

Kummel wrote:On 78rpm's, there were no RIAA curve applied, so only the inverse RIAA curve is needed. I try always to verify the real bandwidth of the recorded signal, and in most of the cases the upper limit is at 4 kHz very coarse. That is ^probably because the engineers expected the 78rpm's to be played with mechanical devices, or with electrical devices having about the same bandwith.
So, in most of the cases, I apply a 50-4000 bandpass filter at the end of the process, all the rest beeing distorsion and hiss.
78's themselves didn't have a whole lot of bandwidth...there is not enough bandwidth...on either end...to worry about what RIAA is doing...end of story. Acoustical 78's indeed were designed for mechanical/acoustical playback as it was the only technology at the time. When electrical recording was used...most electrically recorded discs were engineered for electical playback. This is evident from the RCA Orthophonic players. They were acoustical players that had the necessary modifications to play electrically recorded discs...the fidelity of an electrically recorded disc being much much more than the acoustical variety and were often considered as "harsh" sounding when played back with a traditional mechanical method. Even then, thats not to say they weren't applying some form of EQ that was designed as a "pressing only" EQ. The advantages of pre-emphesis and de-emphesis were realized later...with several curves existing before the RIAA curve was standardized.

Basically...back then...the engineers weren't thinking about limiting frequency response...they were doing EVERYTHING in their power to improve fidelity...not limit it because of mechanical/acoustical playback systems. If they had, then electical playback of discs would of NEVER gone anywhere.

With that being said...some of the later 78's that are in GOOD condition will respond sometimes up to 8 or 9 khz....it wasn't an exact science back then nor were they really had a method of measuring it.

Really, in his case, he should just ignore the fact he's applied RIAA from the pre-amp and go about business. I know...that's techncially not right and as many people know, i'm sometimes pretty anal about doing things the proper way...but when you've got a LOT of LP's and a big project...you tend to focus more on the overall fidelity than what's proper. The extra RIAA isn't hurting things....at all...ok, things MIGHT be a little boomy..just turn the bass down in an EQ.

I also would NOT be so quick to run the same bandlimiting filter each time. One really needs to listen and look at the spectral readout and find out just where the HF starts becoming nothing but noise. Generalizing all 78's in to the same 50 - 4000 category is, in my book, a larger sin than leaving the RIAA in the process.

I mean, think about it, you got 8000 78's sitting around...that's not a pile...that's a ton...that's many many many many many many many months (not hours, months) of time invested in transfer, restortaion and output. If you can shave a minute or two off the total time by skipping an EQ step if you don't find anything noticably wrong with the result...then fine. But, really, it's a 78....the amount of EQ that's going to be applied by RIAA is not going to have ANY.

If it was my project, I'd work it like this.

Transfer and cut audio to remove silence (but not lead-in/out)
Run a pop/click
run gentle basic NR
time warp
another pop/click to get rid of the "78" clicks and scratches that got missed because they took up too many samples (from being slow)
maybe another NR process to rid of additional noise...slightly more aggressive than the first, but still gentle. remember, it's REDUCTION, not elimination.
examine the HF portion spectrally and audibly to see how bad the distortion is.
run a band-pass filter, keeping only the frequencies deemed needed (but not cutting them off prematurely because of the format)
run a harmonic exciter after restoration to "brighten up" any HF that's lost. this merely excites the harmonics of sound and shifts them up to the higher frequencies. this can give dull sounding recordings just the boost they need...provided you don't go overboard.

Would doug is right about getting the 78RPM table...it would save time (it wouldn't affect the EQ deal...really...it would make sure RIAA is in the right area at proper speed, but it'd still be there)...I am from a camp that believes when recording from an analog-source, the slower the source, the more accurate the speed...it's like when I do reel tapes at half-speed...sure..it takes FOREVER, but it sounds nice.

chsiegel
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by chsiegel »

Thank you all so very much. I googled this topic and came up with this site. I've applied the instructions from various posters, and attended to the nuances of different posts. This is just great. I came out with exactly the results I wanted. Thank you again, all of you who posted on this topic.

chsiegel

rec78
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by rec78 »

Hello all and thanks for the response chsiegel, it is appreciated. I had been intending to update this thread.

First of all - I do have a 78 rpm player--my reason for recording them at slower speeds is that some of them are warped and the needle bops at fast speeds so i record some of them at 33rpm when i need to.
I have spent the last year and a half experimenting with goldwave and trying a lot of different things. I now use the following system which is much different than i started with listed above, and they sound great after using the following editing system.

1. I now record the record as low a volume as possible without losing any sounds. This is usually 17-25%, just so that the top of the recorded waveform goes about to the .3 level. That is the 3rd line above center line just below the .4 on the graph. The lower the volume level that you record at, the less noise you will have to get rid of-also it is easier to use the spectrum filter or equalizer.
1.a. Time warp (if recorded at 33rpm-I have set the default here to 234.8 ) If recorded at 78rpm simply skip this step.
2. after recording the 78, i use the mono-mix setting in the channel mixer. (I only use this setting so this is now my default setting).
3. next is pop/click set at 3000 (i set this as the default setting)
4. Now i take a noise print and use the clipboard noise setting at 30% (again i set this as the default setting-sometimes this has to be increased if the record is not in great shape.)
5. next i do a hiss removal of 30 to 35%.
5.a. At this point i remove all noise from the lead-in and exit silences and trim the lead-in to about 1/2 second.
6.next i use the spectrum filter - I have programmed many pre-sets into the spectrum filter but mainly use the equalization curves--Decca, Brunswick, Columbia (early electrics, i.e.) records all sound great after i use this filter.
i bring the master frequency bar to +9db. Sometimes this is too much and sometimes it is not enough so i have to redo this last step sometimes but it only takes a few seconds.
7. i manually remove any unwanted noises.
This whole editing process takes less than 3 minutes. (not counting step 7 which can take some time if a lot of unwanted pops exist.) If the record is excellent or better condition this last step may not be necessary.

Here is where i got the numbers from.
http://users.hal-pc.org/~clement/Restor ... Appendix_B

My question is: how do you calculate the figures in appendix B ? Anyone know how this is done? I have rolloff and turnover frequencies for other record labels but, i would like the numbers to as exact as possible. The closer you get to the the exact numbers, the better the sound.
If anyone knows of any other curve (exact numbers as shown in Appendix B above,please let me know-i will greatly appreciate it, especially for Okeh, Pathe, Victor (I do have some victor curves but i am not convinced that they are precise.) Thanks, Bob

DougDbug
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DougDbug »

That's a great website! I've saved the link.
My question is: how do you calculate the figures in appendix B ? Anyone know how this is done?
Those numbers were not calculated, they were researched:
These curves were taken from two sources on the web. First a set of equalization curves were given at http://www.vadlyd.dk/English/RIAA_and_7 ... reamp.html for a commercially available preamp. The second set was given at http://shellac.org/wams/wequal.html which were taken from an issue of High Fidelity published in the early 1950s. Both of these articles can be used to help you restore old recordings.
The numbers cannot be "calculated" (unless you have the research data), and the only way to measured the various curves would be to have a test record (with calibrated test-tones) from each manufacturer/series. The manufactureres may have had test records for internal use, but I'd guess not. There may have been consumer test records later when they started making "high fidelity" 78's.

For unknown records, I guess you could use a "popular" setting which would attempt to mimic the average/popular record player for a particular era. That would approximate what most listener's were hearing at the time (assuming the listeners had a really good system, which is a bad assumption.)

I understand that you want to be accurate, but if it were me I'd use these curves as a "starting point" and adjust for taste. Many LPs from the 60s & 70s I've digitized have rather dull high-ends, and I'll sometimes give them a little boost. It might not be "authentic", but that's the way it was in the "vinyl days"... Most LPs had rather mediocre sound... As far as I can tell, not much attention was given to sound quality... Once in a while you'd run into a gem, but these were the exception. So, I don't feel too guilty about altering the sound. I'm sure the situation was even worse in the 78 era, and if the EQ sounds wrong I'd attempt to improve it.

DewDude420
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Re: Recording 78 rpm records at 33 or 45 rpm

Post by DewDude420 »

There were no "high-fidelity" 78's. The term High-Fidelity didn't come in to use till sometime in the 50's..and it was a genericzed term to refer to the advancements in audio reproduction/recording.

The RIAA curve was standardized in 1954, adoption took longer.

While people say most 78's had no pre-emephesis, that's not true. They discovered early on, around 1926, that it was necessary to boost or atteenuate frequencies due to new recording methods.

The thing is, research shows that it wasn't till the 40's that there was an attempt to standardize...as each record company was using their own curves. http://en.wikipedia.org/wiki/RIAA_equalization gives a detailed breakdown.

Therefore, when doing 78's, it's more important to EQ the final result to sound right, rather than attempt to figure out the curve.

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