Vinyylikaivertimen käyttöönotto / Rebirth of a vinyl lathe machine beginning from 2021.

Now some most of it in English, too

Most recent <<HERE>> (It's all in this same page though)

Kyseessä on saksalainen Souri - vinylrecorder (Facebook), ( kotisivu), joka hankittiin porukalla n. 2010. Laite on jäänyt aikalailla käyttämättä, mutta nyt ajattelin kokeilla saisiko siitä tolkkua. Edellinen kokeilu muutamaa vuotta aiemmin johti palaneeseen kaiverrinneulaan. Herra Souri ei myy osia muille kuin rekisteröityneille käyttäjille ja rekisteröityminen vaatisi muutaman päivän omakustanteisen käyttökurssin jossain päin Saksaa, ei kiitos. Onneksi löytyi ranskalainen MyShank, josta löytyi uusi neula myös tähän malliin.

19.4.2021 Koeajoa

Pyyhin pölyt laitteesta ja kytkin piuhat paikoilleen. RCA-johdot olivat aika huonon tuntuisia, mutta sain homman valmiiksi. Aloin ottamaan aikaa, mikä kaiverruspäällä menee 10" levyn laidalta keskelle. 2 min 40 sek, ei kovin paljon. Huomasin, että nopeuden säätö ei toimi taikka on koko ajn täysillä. Lopputuloksena olisi hyvin lyhyitä levyjä. Aukaistiin laite ja tutkittiin.

Kaikista komponenteista oli viilattu tyyppimerkinnät pois! Nopeudensäätöpiirissä oli vain yksi transistori ja joka paikassa aina käyttöjännite 12V. Piiriin tuli johdot myös laitteen takaseinässä olevalta RCA-liittimeltä, jota en muista koskaan käytetyn mihinkään, eikä sitä ohjeissakaan ole. Otin laitteen kotiin tutkittavaksi.

21.4.2021 Kaiverrusyritys

Yritin siinä piirrellä jonkinmoista piiriä Groove Motor Distance systeemin toteutukselle. Osoittautui, että takapaneelin RCA-liitätäntä olisi pakko olla oikosulussa, tai ei ainakaan avoin, jotta kytkennässä olisi mitään järkeä. VR:n pääyksikkö tulikn kuntoon laittamalla oikosulku-rca takapaneelin liittimeen.

Huomasin kuitenkin, että oikeassa kanavassa oli pahoja häröääniä. Tarkistin piuhat ja ilmeni, että tämäkin vika on samaisessa pääyksikössä. EQ:n middle-säädössä ehkä, se piti väännellessä pahaa ääntä. En oikein ymmärtänyt myöskään 'Vinyl Optmizer'-modulin toimintalogiikkaa. Yritin silti kaivertaa levyä. Säädöt eivät ole kohdallaan, lopputuloksena oli levy, jossa neula ei oikein pysy urassa.

22.4.2021 Pääyksikkö kunnossa

Aukaisin pääyksikön, yhdistin dat nauhurin inputtiin ja mikserin outputtiin ja laitoin Kämmäreitten vanhan demon soimaan. Oikea kanava tuli hiljaa ja tummana. Tökin piirilevyä meisselillä ja yhdistin piuhalla outputtiin sieltä ja täältä. Kun ohitin oikean kanavan inputin ensimmäisen elkon kytkemällä sen meisselin kärjellä oikosulkuun, tuli oikea kanava kuntoon. Yllätyksekseni se myös pysyi kunnossa vaikka poistin meisselin elkon napojen päältä. Joka tapauksessa se on nyt kunnossa. Pitänee ostaa 8 kpl 22 uF ja 2 kpl 100 uF 25 V elkoja kuitenkin.

Tutkin vähän kaverrusneulaa mikroskoopilla ja yritin asentaa sen suorempaan. todo:

26.4.2021 Lisää osia

Tilasin Amazonista lämpölampun levyn lämmittämiseksi ja mikroskoopin kaiverrusneulan tarkastelua varten. Tarkistin toki kotimaisenkin tarjonnan, mutta tällöin olisin joutunut tyytymään kanalan riippulamppuun ja lasten mikroskooppiin. (A reviewer from future: Oops, I overwrited the picture of el cheapo USB-microscope with something else.)

29.4.2021 Manuaali

osia odotellessa skannasin laitteen mukana tulleen QuickStart-oppaan.

7.5.2021 Posti kulki

Tilaamani mikroskooppi ja lamput tulivatkin jo postissa ja päästiin eteenpäin. Testasin huokeilla IR-mittareilla, että lisälampulla vinyylin lämpötila saadaan helposti 42 C asteeseen, mikä on quick start-oppaassa mainittu lukema. Tutkin kaiverrinneulaa mikroskoopilla ja neula näytti olevan kunnossa.

Mietin tuolla aiemmin, että mitenhän tuon neulan saa puhtaaksi. Näköjään mukana tulleilla litkuilla. Kaikki näyttää hyvältä. Ajattelin, että kirjoitan quick-start oppaan puhtaaksi. Siellä on pikkujuttuja itsensäselvyyksien seassa mitkä pitää ottaa huomioon ja undo-nappia ei ole. Saappaat nähdä. Kesäkuulle asti kuitenkin pitänee tehdä leipätöitä 24/7.

28.7.2021 Back in the business!

Mittailin signaaliketjua yrittäen löytää jonkinlaisen unity gainin, missä mikään laite ei vaimentaisi tai vahvistaisi signaalia ennen päätevahvistinta ja vasen/oikea balanssi olisi tasoissa. Jonkinlaisen kompromissin löysinkin, mikä olisi syytä dokumentoida esim. tänne ihan omaa etua ajatellen. Noh, jotakin hämärää siellä on, mutta close enough for rock and roll ja teippasin osan potikoista juntturaan.

3.8.2021 Lastut lentää tai ei lennä

Tehtiin koekaiverruksia hra Ruokankaan kanssa. Jazzikansa jo hieman odottaa tulevia vinyylipienpainoksia. Säädöissä ja lastunpoistossa olisi vielä hiomista. Elektroniikka ei ole myöskään ihankaan ok, epäbalanssia ja häiriöitä. Ajattelin seuraavaksi lainata Livepaletti oy:ltä dsp:llä varustettua päätevahvistinta, jolla korvaan ns. main unitin. Dsp:llä olisi tarkoitus tehdä RIAA-korjaus. Ylipäästösuodin 20kHz kohdalla -6dB/oktaavi pitäisi olla aika lähellä. Paketin mukana tullut DJ-mikseri joutaisi kanssa esim. johonkin diskoon.

5.8.2021 Käänteinen RIAA-korjain

Tuumin että pitäisiköhän tehdä 'oikea' käänteis-RIAA-korjain eikä yrittää jäljitellä käppyrää eq:lla. Netti on ainakin pullollaan kaikenlaisia kytkentöjä. Ajattelin tuollaista kuvan kytkentää, Ltspice-simuloinniin mukaan voisi olla ainakin taajuusvasteeltaan ihan ok, muistuttaa kovasti esim. Wikipedian antamaa kuvaa RIAA-korjauksesta. Tuosta vaihesiirtokäyrästä (mutkaisempi) en osaa juuri muuta sanoa kuin että virta ja jännite ovat paljolti eri vaiheessa, kuten odottaa sopiikin ja hälläväliä kukaan tiedä mitä siellä kaikkea tapahtuu ennen kuin ura on muoville taikka jonkinlaiselle muovi/etyleeni/vinyyli pinnalle hakattu.

Vaikka työpöytä ja laatikot tuntuvat olevan pullollaan elektroniikan komponentteja, vaatimattomasta varastonhallinnasta johtuen tilasin osat Oulun SP Elektroniikasta

• Kotelo
• RCA-runkoliittimet 4 kpl (Laitan ehkä 1/4" jakit rinnalle, niitä sentään löysin)
• (1k5, 6k8, 75k, 1M) x 2 metallikalvovastukset
• (1n, 3n3) x 2 tarkkuuskondensaattorit

6.8.2021 Hieman konkretiaa

..Kuvan muodossa. Käänteis RIAA kasaamista vailla keittiön vahakangasliinalla. Siinä ei kannata tinata, kokemusta on. Eikä reikiäkään porailla keskellä yötä edes täällä synkässä korvessa, huomisiin jos ruoja suo. Ajattelin kutsua kytkentää vastaisuudessa AAIЯ-korjaimeksi, lyhyempi nimi kuin käänteinen RIAA-korjain ainakin.

8.8.2021 Meiltähän tämä käy

Tuli porailtua reiät lootaan ja tinailtua AAIЯ-korjain kasaan. Kuten kuvista näkyy, maadoitus vaan helposti rungon kautta. Lieneekö ongelma kun 40 dB:tä bassoakin myöhemmin houkutellaan ylös? Testaillaan myöhemmin, voinen laittaa taajuusvastekuviakin, luulisin.

14.8.2021 Proof of concept

Laitoin härvelin kotona tietovehkeeseen ja Voxengo Span näytti seuraavaa!

Aikasen täytellistä. 16.8. jatkamme taas. Vien muassani sinne Arcamin hifi-vahvistimen. Laskeskelin että sillä voi korvata dj-mikserin.

17.8.2021 Voihan taajuusvaste

No niin, DJ-mikseri tuli korvattua Hifi-vahvistimella ja AAIR-korjain paikalleen asennettuna kuunteluelämys oli korviahivelevän täydellinen!

No ei ihan. Lopputuloksena saatiin bassottomia, riipivän kuuloisia levyjä jotka tulivat kuin lankapuhelimesta konsanaan. Jälkeenpäin ajatellen on selvää, että myös kaivertimella on oma siirtofunktionsa taikka taajuusvasteensa, mitä pitää kompensoida.

Suunnitelma: Taajuusgeneraattori kainaloon, kaiverretaan siitä ilman mitään korjaimia oktaavin välein taajuuksia 63 - 16 000 Hz. Sitten kuunnellaan vinyyliä graafisen EQ:n kautta ja tehdään tasomittarin avulla korjaava EQ-käyrä. Sitten siirretään EQ signaaliketjuun ennen kaiverrinta ja katsotaan mitä tapahtuu.

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20.8.2021 Overcoming language barrier, last season recap, and a new visit into studio

From now on I will write in English. Things started to look too cohesive here. By rolling upwards this page you can see some pics taken earlier even if you don't understand the language.

What happened thus far, shortly:

We bought a vinyl lathe, a machine that allows you to cut vinyl records. It collected dust for many years. In the spring of 2021 I finally started to really study the machine. There have been some trouble like failing electronics, rotten cords etc. But first and foremost I think, one has to learn this kind of machine, vinyl cutting is very different from any other media transform method that I can think of.

Current hurdle is that the unit containing cutting equalizer (inverse RIAA in documentation) gives me continuous trouble. As soon as I think it is ok, it starts act strangely again. Signal goes like this:

source audio -> eq/inverse RIAA -> power amp -> cutter head

I jumped into conclusion that rolling my own inverse RIAA, slamming it between the source and power amp should do the trick. Well it did not. The cutting system has it's own non-flat frequency response, very much so. Formally speaking we need a correction that is a convolution of the transfer functions of inverse RIAA and cutter itself.
In practice we can f*k all that and experiment:

1. Take your favourite pink noise generator
2. Cut some noise to vinyl
3. play the vinyl through some amp with a proper phono input
4. Take your favourite FFT plugin and freeze/save/print/memorize that frequency response
5. Invert the frequency response and dial it into EQ that will be between the source and power amp.

I did not have a pink noise generator or laptop computer handy. Instead a hardware sine wave generator was used to generate tones between 31-16 000 Hz with octave interval. That kind of reminded me of the days of my early middle-ages, teaching entry level physics and doing any Fourier transform would take hours if not days ...

By measuring playback in different frequencies, following table was obtained.

By inverting the dB values and normalizing between +/-12 dB, and being quite conservative with high frequencies that might not be reproduced anyway, I ended up with a correction curve like this (source -> eq -> power amp -> cutter: original "main unit" abandoned altogether)

That is quite different from the correction I assumed before:

If anyone needs a box to convert hifi amplifier phono input to line input I have one! [this line occupied for humorous content do not overwrite]

24.8.2021 The Devil is in the details or the cords

Heikki Ruokangas arrived with his laptop loaded with avant garde jazz music. We did proceed with cutting a 10'' blank. It went well. Only when we listened to recording we noticed a strong 50Hz buzz on left side. We did quite a lot troubleshooting.. It appeared to be a bad cord between EQ and power amp. I think it was due to wrong termination in balanced-unbalanced connection, but I trashed that self-made adaptor cord already so I can't tell really.

We solved the cord problem and cutted side B, and that sounded quite nice! We can do it! Sometimes anyways, quite often really woohoo!

As soon as I get my act together there will be only high quality wires that never fails. Occasionally there might be some low quality wires though.

4.9.2021 An Interview?

I was contacted by a journalist who wants to write an article into local paper about this vinyl cutter. I am not sure at all if I need that kind of publicity right now. Propably I will tell people to contact Royal Mint Records. When it comes to get things done, Cameron knows this stuff. Fear is a strong feeling (Hiding behind the st

10.9.2021 An Interview

It was only today I finally realised there might be some other people too, who should be heard concerning the newspaper article. Fortunately one of the owners, Mikko Heikkinen and my brother in arms making those last cuts, Heikki Ruokangas were able to attend in such a short notice of two hours. The other half of shareholders Antti Sutela and Antti Tukio were not able to participate this time, my bad.

The interviewing journalist Arto Kiuru rang the doorbell at 5pm sharp. We've known each other for many years. He has written gig reviews for the local newspaper from eighties till today. I have played in some of those bands. No hard feelings. I'm ok by now.
He took like a thousand of photos. As a natural scientist I understand that increases the probability of good ones by factor of N.

And we talked for an hour or two. I am pretty technically minded with this and it was nice to have some people with a common sense around.

After all it was pretty refreshing to talk about all this with all these people. I think we should do more interviews. If they give us the courtesy we'll cut the interview onto vinyl!

Plans for the next week and some notes to self:

17.9.2021 Nothing done

We have done nothing. I am a farmer. It is harvest time. I try very hard to take it easy but sheesh, summer is short around here. Then again I found the way to handle ground loops! There is some nasty nasty ground loop in the system and this neat little transformer fixes it. I think it is manufactured for automotive.HiFi-people. I'll connect monitoring side through this. No hum any more, I am quite sure it will work beautifully..

9.10.2021 Off Topic

I think David Dowie's album Diamond dogs has the coolest ending of all the records ever made. The song 'Chant of the Ever Circling Skeletal Family' ends with stuck needle effect. An early loop in fact. I bought that record in 1975. Now it seems I just cannot find it any more. Very strange. I think Bowie played guitar surprisingly good on that record too, but not Mick Ronson-good.

11.11.2021 Housekeeping stuff

I put all the stuff in a more spacey rack. From up to down .

• Four band fixed bandwidth parametric equalizer (Arsenal audio by API, EQ-R24)
• Level meter
• Stereo amplifier (Arcam A72, or A52 can't recall)
• Original Main Unit (bypassed, except for stylus heating and movement)
• Vinyl Optimizer (original unit, some passive electronics for stereo width, balance, bass, treble and 'vertical treble' = mono treble, I think)
• monitor select device (L,R,L+R,L-R)
• 15 band mono/30 band stereo graphic equalizer (not connected)
• System Eq (LA audio, see above about RIAA corrections)
• Power Amp (T-amp, nothing fancy)

Also, an order of six records arrived! They want them for xmas. We will do our best and see how it goes.

Ordered 50 black blanks 1.5 and 2.0 mm thick (25/25) and 25 transparent blanks. And 100 labels. 300+ euro, yikes! The transformer I mentioned above absolutely killed any hum in monitoring system. High hopes!

The newspaper article was published too. It is great. The headline goes like "It takes patience to cut your vinyl records at home". So true!

Here are some todos I put onto myself earlier

• Wash a blank with distilled water before cutting
  • I really should try that, Heikki bought 5 litres of distilled water for us.
• Find some mic cords to insert Arsenal R24 for an 'artistic' equalizer.
  • It is done.
• Take that 2mm hexagonal key that you bought with you already
  • That key was too short to be really helpful. It should be about 170 mm long.

25.11.2021 Wow! ... and flutter

The blanks arrived. There is 75 12" blank records now for cutting. Everything seems fine except that turntable won't roll steadily. If there is slighest deviation in the blank record it will sound terribly wobbly. For what I gathered in internet forums I should check the cutting head damper, dashpot. And maybe have a turntable with more torque. I'll be looking for better turntables, but it should be possible make this Technics 1200 work, too. Maybe bearing is bad. Further investigating..

One thing I learned from lathetrolls forum is that cutter head weight should be 40-45 g without dashpot and 15-20g with dashpot engaged. I am not sure if I can trust that wimpy spring scale and my shaking hand. We'll see.

4.12.2021 The Good and The Bad

Good:

• Dashpot is adjusted. I replaced old oil with glycerine.
• Counterweight (50g) and cutterweight (~18g) are ok
• Adjusting cutterhead position allowed much more clearance for suction tube; Now the PVC-thread actually goes into vacuum
• Wov problem mostly away
• I made some really good recordings

Bad:

• Wov problem can still ruin records and I have no idea why it choosed to wov this time
• Static electricity can stop PVC thread from cutter going into vacuum and cutter drives over them -> needle skip
• I've ruined lots of blanks
• My audio interface (NI Komplete audio 6) died in the middle of the session. Replaced it with Yamaha mixer /w USB. Does not sound very good. Is it the DA converter or did I fuck up something else in between? It might be the levels. I must think of metering the wattage going into cutter.
• This takes more time than I thought it would. (Now that I think about it this could be in the 'Good'-department.)
• It is still a hit or miss, if I hit with side A, I'll miss with side B

11.12.2021 Now that is some microscope!

A jeweler friend of mine was kind enough to lend me his microscope. It is Russian device from KGB or some other local organization. Very good optics! Unfortunately, as it is not at all digital and there was no camera, no pics of grooves or stylus here. But the stylus is now in a good position as far as I can see. And I saw quite well!

Like I told you before my Komplete Audio 6 audio interface died last time. Verkkokauppa.com was able to deliver a new one in a timely manner though. The catch is that Mk2 version of Komplete Audio 6 does not work with Windows 7 anymore, Win10 only. On the other hand my Panasonic Toughbook CF-19 laptop does not work with Windows 10. Bummer! Fortunately a non-jeweler friend of mine lent me his SSL 2+ audio interface which has win7 drivers and works well. And it sounded better than Yamaha MG-XU to me (see preceding 4.12. entry). There is something in my screwed hearing system that does not like Yamaha at all. A differently screwed hearing may love Yamaha, no offense here.

• Found out that the 'artistic EQ' Arsenal audio by API is defective. This device is there to act as the tone shaping EQ in the system. L/R channels sound very different, left channel sounds dark weak as compared to right. Bypassed, repair attempt added to todo list (I'm not able to pronounce this last sentence anytime soon).
• Left/Right is not consistent from device to device. Mono would be so much easier in this regard.
• For a while thought that L/R from cutted vinyl is out of phase.
• It was not as judged from cutted 100Hz tone /w earphones.
• Called it a day eventually.

15.12.2021 Cutting some records

Instructions:

Power up everything. Put a blank onto player. Let it roll. Lights on. Wait until blank surface temperature is at 39 C. Suction on. Groove motor on. Cutterhead down. Some spindle at flywheel for initial grooves. Minimal amount of stylus heating on. Music on.

Turntable speed strobo is steady. No wov. All the thread from PVC disappears into vacuum. Between songs one turn at flywheel to make distinction between songs.

At the end some rapid turns at flyweel, stop groove motor and stylus heat. Cutterhead up.

There it is. Turn the record for other side.

Repeat till bedtime.

Here is a short video: cutting vinyl

It really works very nice once everything is set up close enough!

From now on I will show a little more love for our other project: All analog studio Vinylrecorder is not abandoned though.

15.1.2022

I bought an USB-microscope. Dino-lite something 4000-series. So much better than the el cheapo I bought before. That claimed 1000x magnification. Bullshit. This Dino thing is good albeit 10xprice (around 200 eur vs 20eur) I have no pics handy but I will post some in the future.

Soldered some cables. Souri machine is all-RCA, but in practice you have to interface with professional equipment. This fact was partly the problem with above mentioned case with Arsenal audio eq, too. In the picture below, I soldered the ones on the right side to replace the ones on left side. Bat out of adapter hell. These ones are pin 3 grounded BTW.

One has to be careful interfacing balanced and unbalanced gear. In the absence of real balanced i/o some gear needs pin 3 floated, some needs it to be grounded! In my eq case pin 3 was grounded in the left and floating in the right. Thanks for my fellow studio runner Matti Niemi for pointing this out for me. My understanding is: If if the output of balanced gear has an output transformer->pin3 to ground. If the output is electrically balanced->pin3 floating. I'll have to check this.

Nowadays the Arsenal audio EQ runs very nice just like it should.

I think I will give up some outboard gear. Like graphic EQs for inverse RIAA and Souri's Vinyl optimizer. All this is so much easier with computer. Measurements are being made, filters adjusted. More to come.

28.1.2022 Crash and Burn, oder Alles Kaputt

It wasn't much after last posting that the other day I was just minding my own business and cutting some pink noise to improve the pre-eq curve close to perfection. Suddenly other side is missing. What is this? Fuses are okay. Switching some cords with each other led into conclusion that another one of the cutterhead tweeters is gone! I took my knife and stabbed it, after all it was already dead.

Here is a closer look into voice coil seen by Dino-Lite microscope at moderate magnification level.

It is burnt ok. I must admit I've set the power amp volume by ear. My ears are quite sensitive, when they don't hurt everything is okay. Wrong hypothesis. And was there a 1A slow fuse instead of 1A fast that burnt before? Maybe. Flink ist fast, Trage ist slow. F = fast, T = slow. Fragen?

So, next project is to build cutterhead again with new tweeters. Surely it will go well and proves to be be a great learning experience. You'll be informed.

15.2.2022 Galactic cutter-head healer

What I was just saying? Build cutterhead again with new tweeters it says? Fortunately my internet searches were fruitful. Someone has done this before. This thread in Lathe Trolls encouraged me to get on with it.

Okay, I went on buying a pair of carhifi Hochtöner, Sinus Live NEO 25s. The one on the right side has its grille removed with pliers while the one on the left has its original appearance. The online store keeps spamming me about customer feedback for the product. Well somehow I kind of enjoyed breaking the product into parts and use it for entirely different purpose as intended, but surely there is other products that might do it for other people better or for less money, hard to say really:P These were around €40 for a pair and 3kHz HiPass filter boxes were included in the package, useless here.

Basically, there is a cone clued to tweeter dome. Basic trigonometry is of a great help here.

My new tweeters have much more depth than originals, so cones have to be less in depth.

There was some retrial, this geometry seemed to be the best in this case.

The new tweeters did not have a how-you-call-it-a-threaded-hole-in-the-back-dead-center so I had to add one (a rounded piece of 0.8 mm aluminium sheet + 4mm rivet nut + super glue). A 10mm hole had to drilled into back of the tweeter so that rivet nut shoulders fit in.

I prepared some paper cones and sinked them into epoxy resin to attain rigidity. Made four cones to have a chance to pick the best of the bunch. In the below photo is my factory. The epoxy resin is a 2-component stuff, containers are not shown in the picture. Loctite superglue was used for tweeter backplates and that Rapid tool for rivet nuts. Those blue vinyl gloves help you to not to glue your bodyparts together for good. Seriously: use disposable gloves and eye protection. Epoxy resin or super glue is not a nice substance to have anywhere near your eye or umm.. eyes, been there done T-shirt etc. :

It will be ok.

5.3.2022

This is how it looks like now. Ugly as hell I know. Obviously the other side should be replaced too, but I might try some cutting with this first.

6.5.2022 Gotta move

We are happy to announce we'll have yet another talent moving into our studio complex. And he will pay some of the rent, too!

Of course this means something's gotta give. This time it is our planned all-analog studio/vinyl cutting room. As of analog studio we'll fit our reel-to-reel recorder into existing control room. It will act just nicely with our Otari Status desk and computers no problem there.

Vinyl recorder moves into my house. It is nice too, now i don't have to drive 30 km or 20 miles to do something with it. Regarding to cutter head repair it is done but still not tested. Coward? Maybe.

Figure 1. random picture of 1.25kHz sine wave

• Email: ummagumma@mailbox.org