OK gents...now here's a weird one...

I just finished dubbing nearly 200 7-1/2-inch tapes onto fresh, sealed cassettes with marvelous results. After much contemplation and research I decided to archive all those reel tapes onto analog cassettes instead of worshipping at the Alter of the Much Overrated CD. ANYWAY...one of the tapes I found was an audition I made as a 13 year kid trying to get a job at a local radio station. It's hilarious and I don't want to lose it because IT IS SO AWFUL. Unfortunately, the reel-to-reel recorder I had as a kid was of poor quality and recorded the original tape of the audition slow, less than 7.5 ips (maybe 15 or 20% slow) ...so on my good deck it plays very fast. (Yeah, yeah, I know...my voice was a kid's voice so I concede it was higher...but the recording is closer to Alvin of the Chipmunks and the 45 RPMS sound like perhaps 50 RPM).

I've tried digital software to modify pitch and speed and it ends up sounding like crap, largely because digital makes every nuance on the tape a sound onto itself; wow and flutter from the tape is exacerbated with lots of phasing distortion.

Other than changing the size of the capstans and pinch rollers does anyone have a suggestion as to how I might slow up my good recorder to get a reasonable dub of this
(to me) priceless tape?

LONG LIVE ANALOG. LONG LIVE TAPE!

Thanks.

There's no 3-3/4 speed on this RTR deck?
If so, a temporary "fix" could be made of scotch tape carefully added to the capstan to get the right speed, whereafter it can be removed.

Just a suggestion.

I had a couple of Sony dual cassette decks that had a variable speed control on the playback only section. Once I had something I felt played back too fast, so I copied it to a cassette, put it in the playback section and diddled with the speed until it sounded ok, then copied it to another cassette. That gave me the result I was looking for. These were standard consumer grade cassette decks from the mid 80s/early 90s.

You could operate your RR machine capstan motor, or the whole machine on 50 Hz.

There are some places with 50 Hz power. Hard to find them , though.

A 200 watt amplifier connected to a suitable transformer, a 100 Watt 8 ohm
to 70 volt volt line transformer, or even two of them , might work.

Or you could make an induction generator set with the right pulleys ro change
60 Hz to 50 Hz.

Here is the setup I used in electric motor class I taught years ago. It is a
1/2 HP motor driving an old dryer motor. It put out about 90 watts and
the pulleys set the frequency. Capacitors were ripped from old light
fixtures.

Thank you radiotechnician for the incredible (!!!) (albeit Rube Goldberg) arrangement. Gee I wish I had been in your class! Seriously.

I might start accumulating parts for radiotechician's scheme although I am concerned that, at 50 cycles, it might not create an accurate emulation of my voice at the age of 13 years old. (I am determining that point by how the records I played sound on the tape sound...when Andy Williams' voice sounds correct, I'll know I have my own 13 year old voice pretty close.

I am grateful for all the suggestions I've received. Last night I tried severing the leads to a DC motor in an old cassette deck and inserted resistors but could only slow it a little before the motor dropped out. Next I will try the "tape on capstan" trick (which is what the rock stations did in the 60s and 70s to play more music than their competition during an hour...45 RPMs records were upped to 50 or 53 RPM which made more time for...well...COMMERCIALS.) I am sure they actually had their turntable capstans re-machined even though most of them dubbed everything onto tape cartridge in those days.

Anyway, I'll keep plugging away. I appreciate all you guys' helpful advice.

There are reel-to-reel machines with variable speed. The Pioneer RT-707 will vary pitch through a full step in either direction.

The last time I had a chore like this, I used a Sony TC366 with a 50-cycle motor pulley, which is much larger than the 60-cycle pulley. With the machine on 60-cycle AC, it had the effect of raising the pitch nearly two full steps. Depending on the machine you're using, you may be able to get (or contrive) a motor pulley that would do your job for you.

Hope this helps.

Larry

I had a tape of us kids on a Florida trip, made on a Lafayette portable recorder around 1960 with rim drive to the reel (so the speed varied continuously as the takeup reel filled). I solved the problem of transcribing it by using the very same machine (which I still have) to play the tape.

As a kid, I had a little Commodore rim-drive machine; I didn't think anything about the rim drive, and truthfully I didn't even notice it until I tried playing a Commodore-recorded tape on my old Ampro 731, which has a capstan drive. THEN I noticed !.

L

Many years ago, I had to copy a cassette tape recorded when the batteries were so weak that the tape slowed even further when people spoke loudly! I copied it onto a reel to reel Lafayette tape recorder that used a simple AC induction motor. To vary the speed, I just wired a dimmer switch (the type used for a wall switch) in series with the motor lead. I could turn the dimmer knob to slow the speed of the reel to reel recorder to match the slow original tape, so now it sounded correct. (This would not work with a synchronous motor). The output was recorded onto another cassette, which is what you want to do.
You need to slow down your tape recorder, but putting tape on the capstan would make the playback faster.
Don

Doing this in the digital domain is the best way, and is how the professionals do it. Audacity (freeware) has a nice speed correction feature. I've used it very successfully. I don't know why you are having trouble with encoding, maybe a level or impedance problem (PC sound card input impedance is fairly low, 10-20k ohms, may not work well with some tube equipment).

-David

If, the machine has 3.75IPS, carefully wound scotch tape on the capstan to get the proper 7.xxIPS speed needed is a simple task.
Cheap & dirty - and removable.

Plug the deck into a variac and power down from 120 volts until the speed is correct.

That won't work if the deck has a synchronous motor or a regulated DC capstan motor, as many of the newer ones do. I'm not sure I'd try it with an induction motor, 2-pole or 4-pole, for any significant length of time. As I understand it, they tend to overheat when undervolted.

Larry

This a bit cumbersome, but nothing like Rube Goldbergs setup!
Try to calculate how sharp the pitch on the playback is, so you can determine what the speed error is. If you figure its a 3rd sharp, well that's a known ratio. We'll call that the "over pitch ratio".
Measure the decks flywheel diameter and motor pulley diameters. Divide the flywheel diameter into the pulley diameter to get the drive ratio. Divide the over pitch ratio into the drive ratio to get the desired drive ratio. Calculate the needed pulley diameter to achieve the desired drive ratio. Snugly wrap black sticky tape around the motor pulley until the overall diameter is about 1/16" less than desired and shrink a layer of low temperature heat shrink tubing over the tape. If you were consistent with tension when wrapping the tape, speed should be pretty steady, with a minimum of flutter. This wouldn't be good forever, but it should work long enough for your one recording.

On second thought. Buy a better deck with a pitch control and save your time and effort.

TG

Oops. ERROR:
divide the motor pulley diameter into the flywheel diameter. I hit the wrong button and posted before proof reading.

TG

If your capstan motor is a synchronous type, an audio sig gen, set to the desired frequency, into a suitable audio amplifier, and transformer can slow (or speed up), the capstan motor slightly.

Charlie

Didn't notice that this was such an old thread.

C

I don't understand the ongoing complexity here to do a one-time copy of an off-speed tape.
A one-time copy.

My *simple* and quite effective use of using scotch tape carefully wound on the capstan and using the 3.75IPS speed is all it takes.

You wind it on the spindle and adjust the amount till the tempo is sounding right.
Afterwards, you simply peel it off and clean any residue from the capstan.
Done.
I've done it.
It works.

Certainly more simple than complex speed-regulating contraptions talked about on here.

Scotch tape !
I fixed so many tape recorders in the early days all that is left is the hellish thought about
what happened when a splice caused the tape to wind up on the capstan, pulling tape
from the take up and feed side. Jammed up so tight, had to be cut off. Then fix what got
bent or broken.

I'm sure that situation was messy.
But it's not what I was dicussing.

You didn’t mention trying to salvage tape from the tangled mess on the floor after a scotch tape splice wound up on the capstan. An unattended background music tape player with 14” reels could make an impressive pile of tape if the splice was near the beginning of the reel.

The outfit I worked for rented reels of music from RCA and the tapes were quite expensive if not returned. The boss said that it didn’t matter what shape the tape was in, just so RCA got back a full reel of their tape. Had something to do with licensing fees of the music on the tapes. Of course the boss got as much use out of a rental tape as possible by moving it from city to city. Some of those tapes came back spliced with every kind of sticky tape imaginable. Black cloth friction tape was not unheard of!