I'm serious; what part doesn't exist that we'd need? 3D printing and laser cutting are the cheapest they've ever been (eg ponoko). Even the cheapest tape echo units here in the UK cost £150-odd for a working one and they're bigger than my laptop. You can get a hell of a lot for £150 DIYing, right; two cassette players (one to donate a record head), a nice sheet metal enclosure... Hell, you can get a cassette fourtrack for the price of a good cable these days. They have record heads.
Infinite loop cassettes are available cheaply in standard and micro sizes. That's easy enough and there'd be no need for rewinding.
The driving and recovery circuits can't be all that. Are there specialised ICs? Is there more to it than just impedance?
I have no idea how the motors work in a tape player. Is it geared or just hooked straight in to the rotating bit? Could you control the speed with PWM?
I'm picturing a plastic frame from a 3D printer etc. that sits in the enclosure and holds the rollers, motor and heads in place.
If I had £10k, nothing else to do and no plans for next year I'd apply for a patent (lol) but since I don't, do you think we here could come up with a project for the DIY community? It's not just guitarists, I'm sure the synth guys etc. would love something like this.
this is a great idea. other people have done it here, but it has been a while. if the info is in the archive , you might save some headaches in figuring out the details.
a good quality cassette would sound a ton clearer than some of the crap analog delays people covet around here. plus, you would have tape tone. let us know how it goes, please.
Actually, I'm not sure how long it would sound good. While it is/was possible to get fairly robust 1/4" tape, good sturdy cassette-sized tape that can live up to the rigors of a loop of decent length may be tricky. That thin stuff doesn't pack a whole lot of oxide on it. If you can live with answering-machine quality, great. Maybe I'm out to lunch, but I can't see it getting much better than that.
I've seen loops of several minutes, designed for waiting room muzak. How many passes do you think it would hold up?
I've opened up an old walkman here and it's geared with a drive belt. Guess the motors are too fast without. However, the whole assembly (motor, head and roller) came out as one. No room for a second head there though.
Here's a tape motor on ebay:
http://www.ebay.co.uk/itm/CCW-2400-RPW-DC-6V-Cassette-Tape-Recorder-Micro-Motor-/130559236956?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item1e65efdb5c
Is that 2400 revolutions per week I wonder!
Answering machine quality but with sound on sound and long record times would be awesome to me.
I don't have much DIY time these days, HHE, but I support the idea and would love to contribute whatever I can so I can have a DIY tape looper in a reasonable form factor. If you needed others to sign on to get costs lower for your Ponoko or other making projects, you can count me in.
But, I'm not positive that would be the easiest way to go about it unless you're heavily concerned with having it look slick. Standard parts that don't need o be hacked can sometimes make a project more doable, but in this case aligning the mechanical parts and heads properly and getting them set up may end up being such a massive amount of work that it's not worth it. Using ready-made cassette player/recorders, and hacking in the necessary electronics for driving them and doing sound on sound, would likely be a much simpler angle.
As far as driving them, the basic technique is dynamic high end boost in front of tape and dynamic high end cut or de-emphasis after tape. A simpler approach is simply to boost frequencies above 1k before the tape and then cut that same band by the same amount before going to the output, without the compression aspect.
Some experimentation would be good to determine whether the emphasis/de-emphasis works best as a wrapper around the delay, or in the feedback path so it happens each time around. Each would have unique and useful sounds.
I tend toward weird and junky sounds more than hi-fi stuff if I'm bothering about tape or analog, so a simple approach is cool with me.
When I was a teenager I was very into tape. I had a Teac 3 head cassette deck, which means that the playback head was immediately after the record head. I used to feed the output into a mixer and back into the input. very short delays with regen were possible, no control over delay time. Another thing I did was to take two cassettes apart, and have one spool in the first housing, the other spool in the second housing, put two cassette recorders side by side, on on record, the second on playback, run the output of the second back into the first via a mixer, stretch the tapa around the room. Seriously long delays were possible, like minutes. Cassette Frippertronics. I also abused WEM Copicats - by sticking bits of bent card over the record and/or erase heads you could create semi permanebt loops. A couple of years ago I picked up a cheap WEM Copicat and hacked in a DPDT to disable the record head, so you could 'save' a loop of whatever you'd recorded. I did try to control the motor speed with a pot, unsuccessfully - AC motor.
Anyways, the simplest way to go would be to get hold of a 3 head machine and cludge some control over the motor speed. I'm interested but not neccesarily in!
From the world of emulating vintage Meazzi type echoes - as used by The Shadows back in the 60's:
http://charliehall.proboards.com/index.cgi?board=project&action=display&thread=6155&page=1 (http://charliehall.proboards.com/index.cgi?board=project&action=display&thread=6155&page=1)
Erik
Quote from: Taylor on August 21, 2011, 10:16:40 PM
Answering machine quality but with sound on sound and long record times would be awesome to me.
I don't have much DIY time these days, HHE, but I support the idea and would love to contribute whatever I can so I can have a DIY tape looper in a reasonable form factor. If you needed others to sign on to get costs lower for your Ponoko or other making projects, you can count me in.
But, I'm not positive that would be the easiest way to go about it unless you're heavily concerned with having it look slick. Standard parts that don't need o be hacked can sometimes make a project more doable, but in this case aligning the mechanical parts and heads properly and getting them set up may end up being such a massive amount of work that it's not worth it. Using ready-made cassette player/recorders, and hacking in the necessary electronics for driving them and doing sound on sound, would likely be a much simpler angle.
As far as driving them, the basic technique is dynamic high end boost in front of tape and dynamic high end cut or de-emphasis after tape. A simpler approach is simply to boost frequencies above 1k before the tape and then cut that same band by the same amount before going to the output, without the compression aspect.
Some experimentation would be good to determine whether the emphasis/de-emphasis works best as a wrapper around the delay, or in the feedback path so it happens each time around. Each would have unique and useful sounds.
I tend toward weird and junky sounds more than hi-fi stuff if I'm bothering about tape or analog, so a simple approach is cool with me.
The later space echoes used an NE570 compander pre and post delay to do the noise reduction thing and that's pretty easy to add. I think this would be simpler and more durable to build using radio station carts, a dc motor to control speed, and 1/4" tape deck heads kinda like the Univox units. Personally I'm more fond of the open tray multi-head Space Echoes, but that might not be the way to go for a first try. I have an old ratted out consumer, but tube, Ampex deck with good heads that I've been meaning to do this to for years, but my house and more important projects always get in the way.
So a cassette has three access points like this:
(http://i.imgur.com/ewp23.jpg)
If I set it up to be a one head delay with electronic feedback feedback like this:
(http://i.imgur.com/NgYpi.jpg)
One could run the tape extremely slowly; using PWM and a DC motor. I don't know what kind of frequency you'd need but I'm sure a 555 could handle it?
Then the quality of the tape becomes much less of an issue at longer delay times.
You could also if you were feeling particularly clever run the thing in actual stereo. put the two in series for a half/fulltime switch or even have ping pong.
this has been done before but I think the problem you will have with the tape on the cassette is that you can't move the heads like a real tape echo. only one of the heads needs to move. you should make sure that they get as close as possible at one extreme so you can get ultra short delay times. you can still buy endless loop cassettes in 30 second on the web. there was everything from 30 seconds, 1 min, 2 min, up to 5 minutes. they are getting rare now since they are out of production and people throw them out. you might want to put a buffer so the guitar is going into a high z input. you can have a separate knob for saturation and feedback attenuation. you'll also want a clean blend or you wont hear the clean till it hits the playback head. its a good idea to get the right stuff for cleaning tape heads. they are old.
The way you have it labeled looks like it might work pretty well.
Most traditional tape delays use a mono head or stereo wired for mono and use the the whole 1/4" tape to get the limited fidelity that they do. I'm not saying that cassette based is going to sound like crap, but it's going to have extremely limited fidelity especially at longer delay times because slower speeds = more high frequency loss, that's why studio machines run at 30 ips or 15 ips if you want fat bass. Cassettes are extremely thin tape but can last a long time when used at a constant tension, start speeding up, slowing down, and stopping and you're looking for trouble, it may work, but it might not be as reliable as you would like, good thing is cassettes are cheap so it doesn't matter unless it quits in the middle of a song and wraps around the pinch roller. Even the more heavy duty machines are notorious for this behavior that's why the later Space Echoes like the 501 don't start and stop, the tape just runs continuously but that only solved the start/stop problem and not the speed up/slow down.
Don't get me wrong, I'm not trying to poop on your parade because I would love to see somebody get on of these cassette tape delays running someday. I'm just trying to share some knowledge from years of owning tape delays/repairing them for a living
Quote from: EATyourGuitar on August 22, 2011, 02:51:47 PM
this has been done before but I think the problem you will have with the tape on the cassette is that you can't move the heads like a real tape echo. only one of the heads needs to move.
Why? Easier to control the tape speed.
Quoteyou should make sure that they get as close as possible at one extreme so you can get ultra short delay times.
I'm not trying to make a flanger!? I don't care if it goes super short.
Quoteyou can have a separate knob for saturation and feedback attenuation.
"saturation" how?
Quote from: wavley on August 22, 2011, 02:51:57 PM
The way you have it labeled looks like it might work pretty well.
Most traditional tape delays use a mono head or stereo wired for mono and use the the whole 1/4" tape to get the limited fidelity that they do.
Heck, you could easily put a switch for long short that would let you choose between parallel for quality and serial for length!
QuoteI'm not saying that cassette based is going to sound like crap, but it's going to have extremely limited fidelity especially at longer delay times because slower speeds = more high frequency loss, that's why studio machines run at 30 ips or 15 ips if you want fat bass.
If it's not much worse than a PT2399 I wouldn't be arsed!
QuoteCassettes are extremely thin tape but can last a long time when used at a constant tension, start speeding up, slowing down, and stopping and you're looking for trouble, it may work, but it might not be as reliable as you would like
I didn't know that, but like you say they're cheap enough.
Quote, good thing is cassettes are cheap so it doesn't matter unless it quits in the middle of a song and wraps around the pinch roller. Even the more heavy duty machines are notorious for this behavior that's why the later Space Echoes like the 501 don't start and stop, the tape just runs continuously but that only solved the start/stop problem and not the speed up/slow down.
I'm not convinced tape ever has a place on stage tbh. I more see this as a novelty for those of us that think this weird way! I'm not trying to emulate anything, I'm trying to make something new based on an old idea. I'm not anticipating it replacing anything :)
QuoteDon't get me wrong, I'm not trying to poop on your parade because I would love to see somebody get on of these cassette tape delays running someday. I'm just trying to share some knowledge from years of owning tape delays/repairing them for a living
And it's much appreciated.
google is your friend...there are several different projects concerning this out there on the net that i've read several times...but, too lazy..
Lots involving 3 head equipment (usually massive AND requires guitar pandering circuitry in addition) or spliced tapes (god help me and my fat hands)
Can't find much about this particular direction we're looking at with the stock cassette.
oh wise men; how does a record head control the wiping? Is there a DC signal required on one of the pads or is it a bit more complex?
i wish i could remember what the keywords were, but basically i think it was like popular electronics or something, they used a double cassette deck and had an interface where it would feed back one side into the other..giving repeats and echoes...basically almost just literally patched together. if i find it, i'll try and post it.
Quote from: pinkjimiphoton on August 22, 2011, 06:00:06 PM
i wish i could remember what the keywords were, but basically i think it was like popular electronics or something, they used a double cassette deck and had an interface where it would feed back one side into the other..giving repeats and echoes...basically almost just literally patched together. if i find it, i'll try and post it.
I know the type. I'm looking at something a tenth of the size if I can get what I'm thinking working.
One year I got to make the soundtracks for different rooms in the haunted house I worked at. Being that it was 1999 I made the soundtracks in Acid but recorded them to 3 minute endless loop tapes in tape decks for each room. Those were then connected to a stereo system. Anyways, my point... the tapes held up good for a while... but by the end of the season they were pretty shot. Mind you, they were running for 6+ hours 3 nights a week for 5 weeks. Not sure how hard it is to find endless loop tapes now, let alone good quality ones. I'm also not sure how much you'll be using them. For all intents and purposes though they should be ok for your application. I'd be more concerned about using good record and playback heads, as well as good motors to cut down on wow and flutter.
Quote from: runmikeyrun on August 23, 2011, 12:38:25 AMcut down on wow and flutter.
I'm not sure I can speak for HHE here, but all the quirks like wow and flutter are precisely why I'd want to do this in the first place. Plain jane delays and even loopers are pretty cheap these days, so if you wanted something straightforward, a cassette tape delay would be completely the wrong way to go about it. :)
Yeah, if I wanted a digital delay I'd use a PT2399. Unpredictable wow and flutter would be a godsend, not a problem!
Quote from: Hides-His-Eyes on August 23, 2011, 05:16:40 AM
Yeah, if I wanted a digital delay I'd use a PT2399. Unpredictable wow and flutter would be a godsend, not a problem!
That is precisely the reason to own a tape delay.
If you're using a battery powered motor from a portable deck then I'm gonna guess that it's a DC motor already, just vary the voltage to change the speed. I think that the capstan/pinch roller might be a real problem when speeding up/slowing down because if it doesn't keep the exact same tension as your spindle then it will eat your tape. Speeding up/slowing down is the other reason to own a tape delay. Check out the schems for Tascam Portastudios, maybe they will have a clue as to how you might achieve a vari-speed.
Or you could ditch the whole cassette part, disassemble the cassette and take the loop out, ditch the spindle, drive the whole thing with just the capstan/pinch roller like a big machine, and use an open tray. Then you have the option of multiple fixed heads like a space echo or korg stage echo, or a single movable head (now you don't have to fuss with tape speed so much)
The Fender Tape Echo has a really simple path with a tensioned loop and a movable head, but the tape loop length needs to be fairly precise.
(http://static.flickr.com/49/163770865_e9620834f1.jpg)
The Space Echo uses an open tray and it doesn't really matter how long the loop is, you change time with head selection and tape speed.
(http://www.gearslutz.com/board/attachments/electronic-music-instruments-electronic-music-production/117329d1239177907-space-echo-heaven-re-501_1.jpg)
the cassette might work.....you could vary the motor speed to control your echo time. If you record and play at the same speed it should sound fine so changing the motor's speed should allow you to control the dwell time. :icon_mrgreen:
You can't reasonably move the heads in a cassette deck, but changing motor speed does the same thing, and would be easy. After all, the delay is time between record head and playback head. CAssette deck motors, at least anything remotely recent, will be DC motors, but they often are not simple motors. That is, they may not adjust by just changing voltage. Many have little support circuits inside that regulate speed. It would be hard but not impossible to crack one open and remote the speed trim, I guess. SOme do indeed operate on voltage/speed. One could remove the other type and replace with one of those.
Tape tension has nothing to do with motor speed or the pinch roller. Tape decks have back tension, to keep that taut against the head, and takeup tension to collect the tape as it spools past the capstan. Back tension is nothing more than a little drag, maybe a felt slip washer under the reel hub. Take up tension works similarly. Ther wil be a belt or idler tire spinning the takeup reel support, but another clutch disc means it slips over so much tension. SO it is a matter of drag on either end that keeps tape tight, not motor speed.
Fancy three motor reel to reel decks may have back and forward tensions determined by motor servo, but I think that is way past the scope of the original post.
Since the record head and playback heads are against the same tape, it is simple to maintain the same tape speed for both, in fact it is darn close to impossible to have different tape speds betwen the two unless you loop the tape out betwen them and feed it back through at some odd rate.
Audio doesn;t record directly to tape, it is combines with a high frequency "bias oscillator" signal, I forget now 50kHz? 100kHz? A plain old erase head uses the same oscillator without mixing in any audio. The HF bias oscillator scrambles the oxide particles in the tape coating, while the audio modulating it creates a pattern in it. So a missing bias can leave a tape deck able to playback but not record. Fancier decks, and mostly reel to reel have separate erase heads before the record heads. Smaller gear can have combined heads with an erase and a record head in the same "head." Tape is erased just as it is about to reach the record head. One can just bias the erase head to blank the tape. Erasing is the same as recording "nothing."
Tape speed determines the repeat rate, arrange whatever dry/wet balance you like, and feedback level of output signal to input determines the number of repeats.
The Fender delay reminded me of a project I saw where a guy had taken a turntable, glued a piece of 1/4" tape onto a disk, and then mounted the disk onto the turntable. He then attached the record and play heads on the circumference of the disk. One (or bothe) of the heads was movable.
The disk may have been made of foam.
I do not recall if the motor speed was variable other than 33/45/78 maybe a 16 1/2 on the low end with no 78. It was an old style portable school record player.
Food for thought. May be easier to kludge up than a hack into a cassette machine using standard tapes.
Sean
Quote from: beans_amps on August 29, 2011, 09:51:51 PM
The Fender delay reminded me of a project I saw where a guy had taken a turntable, glued a piece of 1/4" tape onto a disk, and then mounted the disk onto the turntable. He then attached the record and play heads on the circumference of the disk. One (or bothe) of the heads was movable.
The disk may have been made of foam.
I do not recall if the motor speed was variable other than 33/45/78 maybe a 16 1/2 on the low end with no 78. It was an old style portable school record player.
Food for thought. May be easier to kludge up than a hack into a cassette machine using standard tapes.
Sean
That's pretty much how the Binson works...
(http://www.hubinet.com/images/BINSON1.JPG)
Hey your right. ;D I guess the guy was trying to copy an Echorec. I had totally forgotten about the Binson. I have never seen one in person. That looks like an easier kludge up than trying to use a cassette recoder.
Sean
I have a sickness, I collect tape delays. I have a huge collection of Echoplexes, Space Echoes, Univox and Melos tape delays. I think I've got more than 20 but less than 30. If anyone needs any gut shots or voltage measurements etc PM me and I'll see what I can do.
Some quick Google-fu gave me this really neat nugget: "using some pretty basic electronics, to turn a regular floppy drive into a controllable tape-style delay and echo/reverb."
http://www.synthgear.com/2010/diy/diy-floppy-drive-echo-delay/
There's a similar thread over at FSB - search "Echo-Matic cassette deck tape delay"
googling brings up this thread: http://homerecording.com/bbs/general-discussions/analog-only/home-made-analog-cassette-tape-delay-project-157157/
and then on our own board here: http://www.diystompboxes.com/smfforum/index.php?topic=80091.0
Dan
Quote from: Hides-His-Eyes on August 21, 2011, 08:53:47 PM
I'm serious; what part doesn't exist that we'd need? 3D printing and laser cutting are the cheapest they've ever been (eg ponoko). Even the cheapest tape echo units here in the UK cost £150-odd for a working one and they're bigger than my laptop. You can get a hell of a lot for £150 DIYing, right; two cassette players (one to donate a record head), a nice sheet metal enclosure... Hell, you can get a cassette fourtrack for the price of a good cable these days. They have record heads.
Infinite loop cassettes are available cheaply in standard and micro sizes. That's easy enough and there'd be no need for rewinding.
The driving and recovery circuits can't be all that. Are there specialised ICs? Is there more to it than just impedance?
I have no idea how the motors work in a tape player. Is it geared or just hooked straight in to the rotating bit? Could you control the speed with PWM?
I'm picturing a plastic frame from a 3D printer etc. that sits in the enclosure and holds the rollers, motor and heads in place.
If I had £10k, nothing else to do and no plans for next year I'd apply for a patent (lol) but since I don't, do you think we here could come up with a project for the DIY community? It's not just guitarists, I'm sure the synth guys etc. would love something like this.
I managed to build a lo-fi tape delay based on two microcassette dictaphones some while ago. I love it, it works with a single playhead and feedback.
(http://3.bp.blogspot.com/-wClw7DxsiPc/UVSe88vthnI/AAAAAAAAAfE/RBm3T0pNU5w/s200/PICT9762.JPG) (http://www.dogenigt.com/2013/03/microcassette-tape-delay.html)
You can find more info, video/sound documentation and a description of how it works and was built on my site:
http://www.dogenigt.com/2013/03/microcassette-tape-delay.html
Brilliant!
Quote from: Mark Hammer on January 09, 2014, 09:35:06 AM
Brilliant!
Indeed! I've been contemplating how one might do this lately myself and I was hoping to figure out a cheap source of 1/8" full-track heads....
Nothing could be much cheaper than The Zone Of Broken Toys in my upstairs room. I have some microcassette stuff up there!
Quote from: tubegeek on January 09, 2014, 07:36:32 PM
Quote from: Mark Hammer on January 09, 2014, 09:35:06 AM
Brilliant!
Indeed! I've been contemplating how one might do this lately myself and I was hoping to figure out a cheap source of 1/8" full-track heads....
Nothing could be much cheaper than The Zone Of Broken Toys in my upstairs room. I have some microcassette stuff up there!
Space echo heads are stereo heads wired in series for mono so stereo heads are not out of the picture.
Quote from: wavley on January 10, 2014, 09:51:20 AM
Space echo heads are stereo heads wired in series for mono so stereo heads are not out of the picture.
I know, but generally stereo heads would be only 1/4 of the width of the tape (typical use is 2 tracks thataway and 2 tracks thisaway.) Mono full track could be a much better way to go.
Quote from: tubegeek on January 10, 2014, 08:04:59 PM
Quote from: wavley on January 10, 2014, 09:51:20 AM
Space echo heads are stereo heads wired in series for mono so stereo heads are not out of the picture.
I know, but generally stereo heads would be only 1/4 of the width of the tape (typical use is 2 tracks thataway and 2 tracks thisaway.) Mono full track could be a much better way to go.
I don't think those heads care which way they're going, I'm pretty sure that portastudio heads are just regular thisaway thataway heads wired to all go thisaway. Maybe a series parallel arrangement would work for any heads out of anything that has auto-reverse. Maybe we can find a use for the useless.
Direction does not matter.
Most consumer formats are "half width" so you can flip it over, use the other side, and double your time per tape-buck. (1/2tr mono, 1/4tr stereo, etc.)
Unless you can salvage some pro gear, you have to get by with half the tape width.
You can get back your S/N by doubling tape speed. In a loop, that only means you need twice as much loop storage. And must replace worn tape twice as often; unless you drop acid and play loopy 13 hours a night every night this is not an issue.
Or, since most of these half-width formats *were* "acceptable", just go with it.
My concern about anything cassette based would be the amount of moving parts making it pretty unreliable. The most classic and reliable tape echoes have a minimum of moving parts that need to be synchronized, the space echo is just an open tray and capstan/pinch roller and works brilliantly. With the number of neglected and useless consumer 1/4" reel to reels out there it just seems that the motors and heads are kind of the least of our worries making something like this, it's really fabricating the mechanical part that's the hard part.
This guy looks like he's on the right track http://www.ghostvibe.com/ (http://www.ghostvibe.com/) Once I was checking out a Shadows forum and there was a guy that had made a beautiful all tube Copicat clone with like 7 or 8 playback heads, I wish I could find it again. I actually have a couple of old decks sitting around waiting for me to take on this labor of love, I already have 101 and 501 space echoes so it keeps getting put on the back burner.
I certainly applaud the efforts to use all those cassette heads for something and saving them from the landfill, I have to say that it is hard enough to get 1/4" tape to behave. 1/4" tape is much less prone to stretching, tangling, and breaking. I'm just saying that in 25 years of owning a space echo I've had tape wrap around the pinch roller and break more than a few times, they are especially terribly behaved if it's really humid... the dozen years I lived in Tampa required almost constant cleaning and tape changing, you better learn to splice a tape and keep plenty of loops handy or you're going to be poor.
That said, there are a lot of microcassette recorders out there that are mono with auto reverse which probably equals a 1/2 track stereo head which can then be wired for mono use of the whole tape and will probably sound pretty good with guitar.
Has anyone tried to use the relatively large number of VHS video record / playback machines out there? You could put two of their heads together, one for record and one for playback and get something with excellent high frequency response. Reliability is one of the reasons they are available used for so little, but for just audio, they might be OK.
amptramp: VHS machines have a relatively complex tape path. Video record/playback happens with a rotating drum that spins at an angle to the tape, not a stationary head, and there is a loop of tape pulled away from the cassette when it loads if I remember correctly.
Having said that, I think the AUDIO track may actually be parallel to the tape, not at an angle - I'm off to google a bit....
EDIT:
Hi-fi audio on VHS tape is some crazy technology!
But it is as I said for the video track - helical scanning on a drum.
The parallel audio track is low fi and mono.
Check it out:
http://repairfaq.cis.upenn.edu/sam/icets/vcr.htm (http://repairfaq.cis.upenn.edu/sam/icets/vcr.htm)
Its cool that you guys are trying to make tape echos with post consumer gear. I really want to work up to that, but so far, all I have done is circuit bend tape players. Just this last week I was doing some recording to tape (there was a bunch "new" tapes in packaging at the Goodwill) and came up with some good results. VHS was just mentioned for its audio portion. Could one have good results recording just audio to VHS? Never thought of that before...
> Could one have good results recording just audio to VHS?
Some VHS recorders won't even record without sync-pulses (a real TV signal).
The Hi-Fi (embedded on video) audio tracks are not awful.
There once was a slick system which digitized audio and dressed it up as "video" so it would pass through the very wideband video channel, then decoded it for play. Target fidelity was comparable to CD. As it was several years before CR-R audio recorders existed, and far cheaper than the early DAT, this was the bees-knees of perfect/cheap audio in its day.
But the topic of this thread is "echo". For that you must record and playback the same tape at the same time. Consumer video decks do one OR the other, never both at once. We could try two decks and hacked-open cassettes to bring tape through one deck then the other. But with the complex VHS (or Beta or Umax) tape path, and slow speeds, it isn't so much an "echo" as "instant replay" (many seconds after the event).
The no-fooling way is a *3 head audio recorder*. Record at the record head, play at play head, the delay is about 100mS-200mS at 7.5ips. At high speed you can push the Haas Effect (well known before Hass from transcontinental telephone). For Seconds of delay you grub another playback head at an appropriate distance from the record head.
To keep going longer than one reel you make a tape-loop. Jigger the safeties so the deck will run, do something to keep slight tension on the loop for good head contact.
BTW, you don't have to use tape for looping. I had a mystery mechanism which looked like a 12" record turntable but with "tape heads" riding on the rim on spring-arms. It recorded on solid iron (like the first magnetic recorders, or later "metal" tape). You'd capture a second and then repeat it over and over. The rest of the contraption tuned a variable filter leading to a stylus which rubbed on wet fax paper wrapped around a cylinder mounted on the turntable. There's an iPod app for that now. But anyway.... you could probably record on a brake drum or disk if you are handy enough.
Quote from: timd on January 13, 2014, 09:41:22 PMCould one have good results recording just audio to VHS?
If the question is about just straight recording, a VHS Hi-Fi deck does have some significant merits: long record times, good quality, cheap media, cheaply available machines, just for a few. As PRR and I have pointed out, the mechanicals would be tricky as hell to try to do an echo unit with a helical-scan video machine.
Back on subject:
Quote from: PRR on January 14, 2014, 03:10:51 AM
I had a mystery mechanism which looked like a 12" record turntable but with "tape heads" riding on the rim on spring-arms. It recorded on solid iron (like the first magnetic recorders, or later "metal" tape). You'd capture a second and then repeat it over and over. The rest of the contraption tuned a variable filter leading to a stylus which rubbed on wet fax paper wrapped around a cylinder mounted on the turntable. There's an iPod app for that now. But anyway.... you could probably record on a brake drum or disk if you are handy enough.
PRR: you lost me at the last turn. What did the stylus/fax paper/cylinder part do?
There is another older technology for echo called an "oil can delay," and there is a bunch of info guess where? Yup, GEOFEX, check it out. Recording is done on a special oil on the surface of a rotating drum, sounds crazy to me but I'm told they can be persuaded to work with some TLC.
Quote from: tubegeek on January 14, 2014, 09:26:32 AM
Quote from: timd on January 13, 2014, 09:41:22 PMCould one have good results recording just audio to VHS?
If the question is about just straight recording, a VHS Hi-Fi deck does have some significant merits: long record times, good quality, cheap media, cheaply available machines, just for a few. As PRR and I have pointed out, the mechanicals would be tricky as hell to try to do an echo unit with a helical-scan video machine.
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Quote from: PRR on January 14, 2014, 03:10:51 AM
I had a mystery mechanism which looked like a 12" record turntable but with "tape heads" riding on the rim on spring-arms. It recorded on solid iron (like the first magnetic recorders, or later "metal" tape). You'd capture a second and then repeat it over and over. The rest of the contraption tuned a variable filter leading to a stylus which rubbed on wet fax paper wrapped around a cylinder mounted on the turntable. There's an iPod app for that now. But anyway.... you could probably record on a brake drum or disk if you are handy enough.
PRR: you lost me at the last turn. What did the stylus/fax paper/cylinder part do?
There is another older technology for echo called an "oil can delay," and there is a bunch of info guess where? Yup, GEOFEX, check it out. Recording is done on a special oil on the surface of a rotating drum, sounds crazy to me but I'm told they can be persuaded to work with some TLC.
I believe the VHS format you're speaking of is called S-VHS, a lot of guys used to master to S-VHS back in the ADAT days, also an S-VHS tape will work in an ADAT. I honestly don't miss either one of those machines, although S-VHS masters can sound pretty good, I hated ADAT's. I wish I could find a blackface one just because I have some tapes that never got mixed down, but geez a lot of the problems of tape and all of the not good of early digital!
These guys http://telrayoilcanaddicts.yuku.com/ (http://telrayoilcanaddicts.yuku.com/) have all you need to know about the Tel-Ray Oil Can stuff. They're actually quite good sounding, but if you think 1/4" heads are hard to source imagine how hard it is to source the rubber heads that are in the oil can.
PRR's mystery machine brings us back to the Binson Echorec, if it's good enough for Syd Barrett, David Gilmore, and Hank Marvin... I'm gonna guess it's good enough for me. Here is a nice description of the drum and flywheel arrangement http://www.effectrode.com/binson-echorec-memory-system/ (http://www.effectrode.com/binson-echorec-memory-system/)
Plenty Alesis adats on fleebay, here is a blackface. Only problem with these is you have no idea how well worn out they are.
http://www.ebay.co.uk/itm/Alesis-ADAT-Blackface-Recorder-w-LRC-remote-MIDI-Sync-Box-8-Track-Machine-/321295822286?pt=UK_Recorders_Rewriters&hash=item4aceb92dce (http://www.ebay.co.uk/itm/Alesis-ADAT-Blackface-Recorder-w-LRC-remote-MIDI-Sync-Box-8-Track-Machine-/321295822286?pt=UK_Recorders_Rewriters&hash=item4aceb92dce)
> S-VHS
No, this was an external audio-only converter for a bog-standard video deck. Never common in the US.
> the Tel-Ray Oil Can
Have one here.
You can also put audio down a pipe. Ma Bell even used that for some testing. Cooper Time Cube is a studio box.
Thought I'd hop in here and share this. There was an old thread on here that I got a lot of useful information from in making this project, but that thread's been dead since 2010 so I figured I'd just leave this here.
I know this is a very old thread but just thought I'd post this as a reference for people...
Here's what I managed to achieve within a Technics Hifi Cassette Deck which uses standard unmodified cassettes:
http://atomicanalog.blogspot.ie/p/flu.html (http://atomicanalog.blogspot.ie/p/flu.html)
Will finish the write-up very soon and do some better sound samples, but it gives an idea of how I did it.
I am also looking into making a more compact unit which could even fit onto a pedal board as a stomp box. There will be a swell pedal to control tape speed/feedback. Just did the first tests this evening:
:D