Recovering 144 Cassette Tapes

RogerStevens

New member
I now record on my computer. But from the mid 80s until 2000 I recorded on a Teac 144 Portastudio.
My portastudio no longer works. I tried to get it repaired, but the expert gave up on it, I've tried to find and buy an old one with no luck. So here's my dilemma.
How do I get the tracks off my old cassettes, and transferred to my computer. Would any other older machines do the job?
They are four tracks and recorded at a much faster speed of course.
 
I now record on my computer. But from the mid 80s until 2000 I recorded on a Teac 144 Portastudio.
My portastudio no longer works. I tried to get it repaired, but the expert gave up on it, I've tried to find and buy an old one with no luck. So here's my dilemma.
How do I get the tracks off my old cassettes, and transferred to my computer. Would any other older machines do the job?
They are four tracks and recorded at a much faster speed of course.

you would need a 4 track cassette for sure. the speed could be fixed in the DAW if necessary.

is there no other place that could repair your device? what exactly is wrong with it ?
 
you would need a 4 track cassette for sure. the speed could be fixed in the DAW if necessary.

Mmm...it won't work changing the speed in the DAW.
If you used a different deck at a different speed, you would also change the pitch, and then trying to fix that would be a mess...but I think maybe with those decks, there was also more to it than just the speed. There might have been some type of noise-reduction used, which would then be tied to the speed also.

Anyway...here's 3 Teac 144 Portastudio decks for sale right now...a couple for parts and one looks to be working.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=teac+144+portastudio&_sacat=0

I also wonder which of Teac's later models would be able to run those tapes...I'm sure there has to be a couple of others besides the 144, but I'm not familiar with the 144 specs to make any comparisons to other Teac models...something the OP should be able to do if he has that info.
 
Mmm...it won't work changing the speed in the DAW.
If you used a different deck at a different speed, you would also change the pitch, and then trying to fix that would be a mess...but I think maybe with those decks, there was also more to it than just the speed. There might have been some type of noise-reduction used, which would then be tied to the speed also.

Anyway...here's 3 Teac 144 Portastudio decks for sale right now:

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=teac+144+portastudio&_sacat=0


well if there were noise reduction then maybe if it were tied to the speed. but that would seem strange if it were. pitch maybe, speed no.

my DAW can change the time of duration so that you can adjust for any speed differences.
This is not changing pitch. this is strictly changing duration so that the pitch comes out the same as if the deck were at the right speed.

if he can buy a working deck he would be better off. transfer the tapes to HD then get rid of the old equipment before he is tempted to use it again with more problems.
 
well if there were noise reduction then maybe if it were tied to the speed. but that would seem strange if it were. pitch maybe, speed no.

my DAW can change the time of duration so that you can adjust for any speed differences.
This is not changing pitch. this is strictly changing duration so that the pitch comes out the same as if the deck were at the right speed.

if he can buy a working deck he would be better off. transfer the tapes to HD then get rid of the old equipment before he is tempted to use it again with more problems.

His problem is not the DAW speed change...but a deck speed change.
IOW, he needs to transfer...so if some other deck is at a different speed, then the pitch will change before it ever gets to the DAW.

Also speed change without pitch change in the DAW is not without a price.
If there is a phrasing that requires 3 seconds...and you now use the DAW to change the speed so that the same phrasing occurs across 5 seconds...it won't be the same.
 
His problem is not the DAW speed change...but a deck speed change.
IOW, he needs to transfer...so if some other deck is at a different speed, then the pitch will change before it ever gets to the DAW.

Also speed change without pitch change in the DAW is not without a price.
If there is a phrasing that requires 3 seconds...and you now use the DAW to change the speed so that the same phrasing occurs across 5 seconds...it won't be the same.

exactly

if the deck runs 2x as fast as the regular cassette the pitch will be higher

but if you slow it down 1/2x the speed will be correct as will be the pitch

the phrasing works out just fine too.
as long as the daw fixes it to play at the correct speed it will have the same length pitch phrasing everything
the only risk might be digital errors do to interpolation or extrapolation so be sure to make the copy at at least 192 and 24 or32 deep

believe me this does work fine if you dont overthink a lot of irrelevant issues and try to fix them needlessly so as to end up screwing thing up
 
Mmm...again, he needs to find a deck, and it's the deck that will mess up the pitch if it is a different speed.
So at a different speed/pitch...the formants and timbre will be changed.
I'm not sure how easy it would be to fix those things in the DAW...and I've messed with them enough to know it's one thing with a single source, never mind with multiple sources.

AFA the time stretch...there's a point where it doesn't really work. All depends on how much. If you have 4 notes that are exactly 1/4 second apart when played normally, which mean they use up 1 second total...and now you stretch them to play across 2 seconds...it doesn't work, even if their pitch is constant.

I know you're saying that whatever the changes, they can be "reversed" back to correct in the DAW...but I'm not very optimistic.

But all this is quesstimation until the OP finds a deck that can play back those tapes...at any speed. :D
 
Mmm...again, he needs to find a deck, and it's the deck that will mess up the pitch if it is a different speed.
So at a different speed/pitch...the formants and timbre will be changed.
I'm not sure how easy it would be to fix those things in the DAW...and I've messed with them enough to know it's one thing with a single source, never mind with multiple sources.

AFA the time stretch...there's a point where it doesn't really work. All depends on how much. If you have 4 notes that are exactly 1/4 second apart when played normally, which mean they use up 1 second total...and now you stretch them to play across 2 seconds...it doesn't work, even if their pitch is constant.

I know you're saying that whatever the changes, they can be "reversed" back to correct in the DAW...but I'm not very optimistic.

But all this is quesstimation until the OP finds a deck that can play back those tapes...at any speed. :D




any 4 head deck even one that messes up the speed will fix the problem of getting the tapes into digital form on a DAW
hopefully he finds the same deck with the same speed and avoids it completely.

either i wasted 5 years of my life in graduate school or you can fix the time problem in a DAW without any issues except sample based errors if you have to up/down sample with too few. imho you are drastically overthinking the problem.
 
Yeah I’m not seeing what the issue is with using any 4-track Teac machine even if it is double speed. Assuming the OP has a 4-channel audio interface to get the tracks into the DAW simultaneously (and a multitracker with individual track outs for each track is used), at double speed the pitch will be up an octave. Cut the speed in half using the DAW and the pitch will be back down to normal. Ideally a standard speed machine is found and used...that will offer the best resolution potential, but honestly even if the interface only does 96kHz sample rate, if it was me, if I could only find a double speed multitrack machine I’d transfer at the max sample rate, and then convert the tracks to half that sample rate...done. If the interface is 24-bit, really, even transferring at 88.2kHz and converting to 44.1kHz is no sort of crime.

I need to look at the 144...I can’t recall if there is onboard n/r and if so what kind. Maybe the OP can share? Because even if there IS onboard n/r there is still the factor of whether or not it was used on the material she/he wishes to transfer. If it is dbx and it was engaged, you should be able to reproduce with any dbx equipped machine assuming the 144 was relatively in spec at the time of tracking and the reproduce machine is relatively in spec. If some other n/r was used (such as Dolby B), that will make it a little harder to find but not at all impossible...jut wasn’t as common on the 4-track cassette machines.

And outside of ALL the above I too am curious about what the problem was that could not be fixed on the 144. To the OP what is wrong with the 144?
 
at double speed the pitch will be up an octave. Cut the speed in half using the DAW and the pitch will be back down to normal.

Additionally, recording at double the speed will, as you say, raise the pitch an octave and halving the speed in the DAW will return it to the correct speed, but this will also give you the original formant.
 
I think the potential issue at hand is that some Dolby NR schemes are based on companding different frequency bands. So, if you encode something at one speed and attempt to decode it at another speed, with everything shifted an octave up or down, it's liable to end up in a different filter circuit than was intended.
I'm not sure if Dolby C or S work that way, though - 'C' is supposed to be based around two 'B' decoders, but whether they're in series, or parallel with different frequency bands I have no clue. Obviously if this is B or DBX encoded it's kind of moot anyway because they have a single band anyhow. In any case, the effects can't be that bad or you wouldn't have varispeed controls on the decks.
 
any 4 head deck even one that messes up the speed will fix the problem of getting the tapes into digital form on a DAW
hopefully he finds the same deck with the same speed and avoids it completely.

either i wasted 5 years of my life in graduate school or you can fix the time problem in a DAW without any issues except sample based errors if you have to up/down sample with too few. imho you are drastically overthinking the problem.

I'm not overthinking anything...and I didn't have to go to graduate school to know that you can do all kinds of numerical crunching with a DAW. ;)
I'm concerned about the mechanical aspects of the original deck and the yet-to-be decided upon surrogate deck, operating at a yet-to-be disclosed speed.
Do we even know at what speed the original deck operated...?

I'm curious...besides the theoretical considerations...how many times has anyone here taken a cassette tape that was recorded on a high speed deck...played it back at a different speed on a different deck...transferred that into a DAW...and then used the DAW's time stretch and pitch correction to make it sound exactly like it did when it was played on the original deck that it was recorded on...?

But that really wasn't even what I was talking about.
I know that if you just focus on the numbers, it's all basic math...but time stretching the audio in the DAW is not the same thing as doubling or halving the original tape speed, and you can only stretch an audio track to a point before it doesn't sound right.
Again...this is non-graduate school, simple stuff... :) ...if you record 4 notes played at a tempo with each note 1/4 second apart...and then you want that stretched to last for 2 seconds...it won't sound the same, even if the notes stay on pitch.

At any rate...I'm a simple guy, I want to see it to believe it, because too much theory sounds good, and then you find out that the audio doesn't sound quite right after it's been sped up, slowed down, time stretched and pitch-shifted into submission...but we are so far ahead of the reality here that starts with first finding an appropriate playback machine or at least trying to figure out what's wrong with the current machine.
So I'm not really the one overthinking it...let's start with Step 1. :D
 
Per Teac 144 manual...it runs at double-speed 3 3/4 ips..and it uses Dolby B-type NR...and they even tell you that if you use the provided pitch-shift option of the deck, you can mess with the Dolby.

TBH...I actually think the first consideration will be...are these cassette tapes from 35 years ago even playable....?...but without a deck, can't know that.
 
I'm not overthinking anything...and I didn't have to go to graduate school to know that you can do all kinds of numerical crunching with a DAW. ;)
I'm concerned about the mechanical aspects of the original deck and the yet-to-be decided upon surrogate deck, operating at a yet-to-be disclosed speed.
Do we even know at what speed the original deck operated...?

I'm curious...besides the theoretical considerations...how many times has anyone here taken a cassette tape that was recorded on a high speed deck...played it back at a different speed on a different deck...transferred that into a DAW...and then used the DAW's time stretch and pitch correction to make it sound exactly like it did when it was played on the original deck that it was recorded on...?

But that really wasn't even what I was talking about.
I know that if you just focus on the numbers, it's all basic math...but time stretching the audio in the DAW is not the same thing as doubling or halving the original tape speed, and you can only stretch an audio track to a point before it doesn't sound right.
Again...this is non-graduate school, simple stuff... :) ...if you record 4 notes played at a tempo with each note 1/4 second apart...and then you want that stretched to last for 2 seconds...it won't sound the same, even if the notes stay on pitch.

At any rate...I'm a simple guy, I want to see it to believe it, because too much theory sounds good, and then you find out that the audio doesn't sound quite right after it's been sped up, slowed down, time stretched and pitch-shifted into submission...but we are so far ahead of the reality here that starts with first finding an appropriate playback machine or at least trying to figure out what's wrong with the current machine.
So I'm not really the one overthinking it...let's start with Step 1. :D

he should know what speed the original was at
or even what the new deck runs at -- although that would help a lot
but still irrelevant
if he knows how long the original track was
that is sufficient to restore the proper speed

as long as the heads track the right tracks then the speed is irrelevant
there is NO PITCH CORRECTION! at all
when you fix the speed it all comes out in the wash less any digital up/downsample artifacts
and possibly the high end response based on different tape speeds

when the tape plays it back at the wrong speed
the DAW does not care about the speed
you set the start and stop point to be the same as the original would have been
this has NOTHING TO DO WITH TEMPO OR PITCH
you set the length the same and then play it normally
a close analogy would be compression and decompression of zip files


i have done it
it works
try it for yourself and see
it works
it sounds right after it has been put back to the correct speed
this has nothing to do with time stretching pitch or anything else
of course playing it at the wrong speed will sound different
 
Additionally, recording at double the speed will, as you say, raise the pitch an octave and halving the speed in the DAW will return it to the correct speed, but this will also give you the original formant.

exactly

you dont to mess with pitch correction or worry about tempo or anything else
 
Again...you're proving the math works...which is not what I'm even debating, other than when you brought up time stretching.
I mean, it's basic math, like I said.

What I'm talking about are the "if" and the "should" and the "as long as"...and the differences in tape deck transport functionality between the original deck and whatever other deck will be used...never mind any DAW resampling artifacts.

The other consideration is what's the intent of the OP with this...to simply get anything he can salvage off the old tapes, in which case quality may not be a real issue if he plans to rerecord the material but needs the old tape tracks for reference...
...or is it to do a perfect transfer without any degradation of any type so he can use them....and would the OP even understand the whole process?

Oh...and there actually IS pitch correction/adjustment happening...because when you play a high speed tape on a normal speed deck, it will play back slower, which is a different pitch....then you have to get it back to the original pitch in the DAW. So you are in fact manipulating the pitch twice.

But we are again going well ahead of where the OP is at....so let's wait for him, and then do Step 1. :)
I also doubt he knows the *exact* length of each track/song on these tapes to be able to set the start/end points in the DAW after transfer.

I know that you and I both understand the fundamental math and process...but we are also looking at the whole thing from two different perspectives.
 
Again...you're proving the math works...which is not what I'm even debating, other than when you brought up time stretching.
I mean, it's basic math, like I said.

What I'm talking about are the "if" and the "should" and the "as long as"...and the differences in tape deck transport functionality between the original deck and whatever other deck will be used...never mind any DAW resampling artifacts.

The other consideration is what's the intent of the OP with this...to simply get anything he can salvage off the old tapes, in which case quality may not be a real issue if he plans to rerecord the material but needs the old tape tracks for reference...
...or is it to do a perfect transfer without any degradation of any type so he can use them....and would the OP even understand the whole process?

Oh...and there actually IS pitch correction/adjustment happening...because when you play a high speed tape on a normal speed deck, it will play back slower, which is a different pitch....then you have to get it back to the original pitch in the DAW. So you are in fact manipulating the pitch twice.

But we are again going well ahead of where the OP is at....so let's wait for him, and then do Step 1. :)
I also doubt he knows the *exact* length of each track/song on these tapes to be able to set the start/end points in the DAW after transfer.

I know that you and I both understand the fundamental math and process...but we are also looking at the whole thing from two different perspectives.



you are quibbling whether digital really equals the analog again

any pitch correction that happens is incidental to the speed change
i am not manipulating the pitch but changing the speed twice
you can , at least my DAW and gear can, change the pitch at the same speed

if he does not know the exact length there might be some trial and error
or else he can spot a note he knows and see what happened to it to figure out what to change to undo that

 
you are quibbling whether digital really equals the analog again

Nope...not at all.
I'm talking mostly about the analog side...which you've sorta left hanging with the "if", "should", "as long as"...and you're just restating the math capability of the digital side, as though it will magically fix all the analog side potential issues using simple math.

When you have all the known quantities in front of you...it's easy to compute...but when much of it is dependent on "something" you don't know yet...I'm not one to just assume it will al be perfect anyway, and if it's not, we can just massage it and fudge it into perfection because a DAW can do anything.
 
Nope...not at all.
I'm talking mostly about the analog side...which you've sorta left hanging with the "if", "should", "as long as"...and you're just restating the math capability of the digital side, as though it will magically fix all the analog side potential issues using simple math.

When you have all the known quantities in front of you...it's easy to compute...but when much of it is dependent on "something" you don't know yet...I'm not one to just assume it will al be perfect anyway, and if it's not, we can just massage it and fudge it into perfection because a DAW can do anything.

let me just say that i have done it
others have done it
it is not that big a deal to do it

perfection is not possible
tape is very imperfect
changing speed will cause issues with tape if the new deck is different from the original
up/down sampling will cause minor changes

he wants his old recordings back
so as you note he needs to find some 4 track cassette to play them with
then i claim the rest is not hard to do and he wont tell the difference unless he is a golden ear type
and he wont care unless after cassette he suddenly got religion about shortcomings in the audio
 
let me just say that i have done it
others have done it
it is not that big a deal to do it

Never said it was.
I'm also pretty sure your situation didn't have as many "unkowns" as the OP's...which makes things a lot easier.

perfection is not possible
tape is very imperfect
changing speed will cause issues with tape if the new deck is different from the original
up/down sampling will cause minor changes

That is what I was talking about. You can't fix that shit in the DAW...it doesn't posses magic powers.

he wants his old recordings back
so as you note he needs to find some 4 track cassette to play them with
then i claim the rest is not hard to do and he wont tell the difference unless he is a golden ear type
and he wont care unless after cassette he suddenly got religion about shortcomings in the audio

We can only assume what his intent is and how critical any of this needs to be.
Will he ever come back and tell us what the problems are with his deck and what's he planning to do with the tracks....?
I'm still betting the tapes don't even play all that well after 35 years. I've seen it happen all to often with cassettes, because as you say, they have a lot of shortcomings.

So what high-speed deck did you have tapes from that you had no choice but to play on a different speed deck into a DAW...?
 
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