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30 ips. Cassette Recorder

Increase capstan drivespeed, via increasing motor pulley circumference, twenty times
  (+6, -4)
(+6, -4)
  [vote for,

Purchase a twin cassette portable tape cassette recorder/boom box, used, for $2-5. Select a model with the slightly larger diameter capstan, there only seems to be two regular sizes.

Take it apart and remove the capstan flywheel from the 'player' deck and replace the motor drive pulley with it. Take the larger rubber drive belt from the player and use it to drive the recorder capstan pulley/flywheel from the motor pulley/flywheel.

The record equalization electronics will to be changed from emphasizing so much high end, NAB curve, so the bass trap filter should have increased resistance in it.

A 120 minute cassette will now last 3 minutes one side but you have a studio quality recorder for $5. I have eight of these in parts and it is tempting to funrun them syncronously to make a 16 track recorder. The heads would wear out in a couple of months, no doubt.

mensmaximus, Jan 12 2005

(?) Low-cost digital recording http://www.musician...il/base_pid/240390/
[csea, Jan 13 2005]

(?) Perpetual Tape Head Power? http://www.theveryl...oulos/questions.htm
Many claims on this site about running tape fast over tapeheads. Who knew? [mensmaximus, Jan 15 2005]

(?) Frippertronics/Soundscaping http://www.loopers-...frippertronics.html
"Andre LaFosse contributes this fine article on Frippertronics, the system used by Robert Fripp in his pioneering forays into looping. Enjoy..." [Ian Tindale, Jan 16 2005]


       Not only will the heads wear out, but you won't gain much fidelity from the faster tape speed unless you record 16x the magnetic flux through the head (I think I recall normal cassette tape "0" level is around 200nW/m fluxivity, and since you are passing 16x the tape, you should bump up the record current to match.) Unfortunately, this will cause major crosstalk, unless you only record one channel / head.   

       In theory, you should be able to increase the record bias / record current by 12dB to take advantage of the increased tape speed.   

       I think you will see some of the infrasonic wobbles of the transport, and some head scrape noise moved up 4 octaves (e.g. 10 Hz will show up as 160Hz, 15Hz at 240Hz) and become annoying.   

       Overall, you'd be far better off going digital to a PC; it's pretty cheap these days, and much better fidelity than you are likely to achieve by mucking around with cassettes.   

       Anyway, good luck with your "funrun" to build a 16tk.
csea, Jan 12 2005

       Isn't digital @$400 a channel? Thank you for the info. i was fishing around for a comment like yours to see where the flaw was. The bias frequency may have to change to help with the magnetic flux transfer. I like electro-mechanical devices in general. It may keep my hand/eye/brain co-ordination skills tuned longer, better than PC.
mensmaximus, Jan 13 2005

       There are high-quality sound cards at all price points, here is a 2-channel card for $99.95 [link]   

       Yes, you would need a PC, but I'm guessing you have one, as you are posting here...
csea, Jan 13 2005

       Some people post from the public library.
robinism, Jan 13 2005

       Thanks Csea for the 404 info. I'm using a pentium one on the internet; I'm infected right now, Norton won't load, i can't play dig. imported; it stalls every twelve seconds but at least I have a house to myself with the rent paid; lots more than many I know right now. The 404s need a pentium three or better. I will buy a used computer dedicated to audio, four track minimum. I really need twelve tracks to record 10:2 sound. Dream...dream. i made my own holophone eliptical mic out of wax but it needs senheisser condenser capsules. See Ling's 360° x 360° Spherical LED Monitor and link to men's guitar picture. There's LED stuff i'm supposed to be working on there but I thought the cassettes would look cool on the guitar; maybe not but i need tape effects. See the exotic guitar site for a motorcycle miniature rear-end as part of a guitar. i just timed my cassette. It is running at 7 3/4 ips with low belting. I may stay with that if i have probs at the next tests of higher speeds.
mensmaximus, Jan 13 2005

       This is fantastic, [mens]! Of course it won't work well for the reasons outlined, but I would love to know how you get on with it.
wagster, Jan 13 2005

       I'm sure that there is already something like this on the market...
DaveW-H, Jan 13 2005

       There's an assembly line of two kinds of cassette decks here. I have to swap motor mounts on some of the decks because there isn't enough clearance to install the flywheels on their shafts but the motors may have to stay with the original decks because of wiring. So there are about thirty things working themselves out through the project. I found a dual drive, reversing, four track head deck that should go on the guitar, seperate from this.   

       The cassette decks are modular I noticed and could be attached in a line with their universal hinges. The parts I found in a $5 scanner the other day! Four thin front surface mirrors and a one quarter inch thick fluorescent light ten inches long runs on twelve volts. The guitar runs on twelve volts, many amps to run its motors and lights.   

       The fellow with the one piece gyroscope: I'll attach one around a guitar string and pick up the signal.
mensmaximus, Jan 13 2005

       How are 300 amps generated out of a VHS tape head pick-up? See link.
mensmaximus, Jan 15 2005

       Wow [mens], that's one insane site.
wagster, Jan 15 2005

       [wagster], I don't agree with his politics if that's what it's called but he's running things at one metre a second towards five, DC bias, one MHz, interesting. i have to find forty Hz on the net or use bell tone to set the bias current on my cassette project. I have the corners cut off two cassettes so that the tape can run from one deck to another. One head will record and the other will play back to check the 40 Hz. As I have twenty of these cassette decks here, I can see making a kinetic art piece out of them with bits of mirrors bouncing control lights at each other. If i can frame it, it will sell in this world.
mensmaximus, Jan 15 2005

       mensmaximus, - are you familiar with the term "Frippertronics"?
Ian Tindale, Jan 15 2005

       [Ian], thank you, I didn't know the name for it. I have strung 35 mm. mag from the recorder through seven consecutive playback dubbers with old type mag, run them in interlock, brought each dubber up to a fader on a mixing board. I remember doing it late one night in a studio while I was checking tape head alignement from head to head. I think I can remember it as being an unsettling sound montage. The new mag won't break and it is dangerous to try this if something goes wrong.
mensmaximus, Jan 15 2005

       If you could find a used Reel-to-Reel machine, it'd probably sound almost as good as the basic idea you've proposed. 7IPs (and it'll be configured to handle it), thicker tape, and if used properly, studio fidelity that'll rival most cheaper soundcards. Qudos on the idea though, I'd always asked my father why someone didn't just do that... And if you got one of the newer cassette tape-decks that searches for the next track (listens for a blank space), it'd be designed so as to ensure that having the head touch the tape as it fast-forwarded wouldn't wear it out. Also; getting an auto-reverse cassette deck would yield 4 tracks of usable audio per-tape, if 'reconfigured'. Just a note though, I had a cheap Microcassette dictaphone, and since it was cheap, it let you fast-forward while you recorded. The quality was actually pretty impressive, all things considering, but since it didn't use its capstan (which was pretty shoddy in the first place), you had to play it back with the batteries the same level as when you recorded it at, or it didn't sound quite right.
{WhiteFang}, Jun 19 2005

       I don't remember who manufactured it, but around late 80's, early 90's there was a really cheap video camera/recorder system avail. that put video on conventional audio cassettes, running the tape around 14 ips. Each tape was good for about seven minutes. It was marketed to kids.   

       It eventually got pulled; not enough interest.
elhigh, Jun 27 2005

       It's not like I forgot this project. I have a Hi 8 camcorder completely apart here. The idler arm positioning mechanism seems to be the weakest link. It's such a mess I went back to soldering rows of LEDs instead. I'm waiting for three DOA camcorders to arrive from an Internet auction site, all the same model. I'm recording on three of them at the same time. Six track audio, CD quality. Actually this is only possible off the shelf with Canon XL2s in free-run time code mode. They are are all started with the same remote control and will all stay locked to the same frame.   

       The world awaits shipment of the new Panasonic AG-HVX200, a tapeless HD camera for under $10,000, anytime soon...soon.
mensmaximus, Jun 28 2005

       [elhigh] The Fisher-Price Pixelvision toy camcorder put anything *but* conventional video on audio tape - the video was black and white, 15 fps, and less than 100 lines of resolution - I'm guessing a bandwidth of around 100KHz tops. Used a stero head, recording "video" on one channel, audio on the other.
TolpuddleSartre, Jun 28 2005

       I remember it. The Watergate security camera.
mensmaximus, Jun 28 2005

       15 FEET per sec? Oy!
elhigh, Jun 28 2005


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