Tape Speed Question - Akai GX-4000 D

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Eric Altizer

New member
I have open reel tapes recorded at 1 7/8 ips, 3 3/4 ips, 7 1/2 ips and 15 ips. When I play them some of the tapes sound fast and some sound slow when I play them on my Akai GX-4000 D ( I like my Akai! ). The tapes recorded at 3 3/4 ips sound just fine. Some of the others play too fast. Does anybody know what tape speeds I can play on this tape deck and how I can adjust the tape speed setting on this tape deck? Do I need a different deck for the tape recorded at 1 7/8 ips or can I adjust the speed of the recording "in the box" with some software program? :confused:
 
Eric Altizer said:
I have open reel tapes recorded at 1 7/8 ips, 3 3/4 ips, 7 1/2 ips and 15 ips. When I play them some of the tapes sound fast and some sound slow when I play them on my Akai GX-4000 D ( I like my Akai! ). The tapes recorded at 3 3/4 ips sound just fine. Some of the others play too fast. Does anybody know what tape speeds I can play on this tape deck and how I can adjust the tape speed setting on this tape deck? Do I need a different deck for the tape recorded at 1 7/8 ips or can I adjust the speed of the recording "in the box" with some software program? :confused:
Click to expand...
The Akai 4000s can run at 3.75 and 7.5 ips. This is achieved by adding a small collar to the capstan to change its diameter. If you don't have the collar, you might be able to get a replacement (I think someone was making them).

You can of course varispeed them in software, although you probably won't get quite as high a quality as playing them properly would do. Nearly all software that can record sound can do some kind of speed change (even Windows 3.1 sound recorder!)
 
1 7/8 ips

Sounds good. I will check into getting the capstan collar for the 7.5 ips. Some of my reels are marked that they were recorded at 1 7/8 ips. I know that this is the standard speed for 'cassette' recordings. How would I go about playing a 1/4" reel at this speed? Would I need to get an even older deck that plays at this speed or could I play it on a Tascam with speed control? I mean was there a time say pre-1980's that reels were recorded at 1 7/8 ips?? Or is that not possible?
 
Eric Altizer said:
Sounds good. I will check into getting the capstan collar for the 7.5 ips. Some of my reels are marked that they were recorded at 1 7/8 ips. I know that this is the standard speed for 'cassette' recordings. How would I go about playing a 1/4" reel at this speed? Would I need to get an even older deck that plays at this speed or could I play it on a Tascam with speed control? I mean was there a time say pre-1980's that reels were recorded at 1 7/8 ips?? Or is that not possible?
Click to expand...
Tascam varispeed is only usually +/- 15%, sometimes 10%. Unless you can
get a consumer deck with this speed (or perhaps a Tascam 34-L, which was
used for logging.. think the interrogation recorder in 'The Usual Suspects'),
you will probably have to play them back at 3.75 ips and halve the speed in
software.
For Windows, Goldwave is quite nice but it is shareware. Audacity is free and also works in MacOS and Linux, but is a tad ugly and tends to save as useless .aup files unless you remember to use 'Export' instead of Save.

Pretty much anything that can edit audio should be able to change the sample rate.


*EDIT*
My Uher Report 4000L can run at the following speeds:
7 1/2, 3 3/4, 1 7/8 and 15/16 ips. (That's fifteen sixteenths, not 15ips).
This particular machine is mono half-track, but there was also a 2-track
stereo machine, the 4200, and I believe the 4400 was 4-track stereo, like
the Akai. You haven't actually mentioned the track format of the tapes. When playing them on the Akai, do the tapes have two sides, or only one?
If they can be turned over, you'll be needing a 4-track stereo machine.
 
Yes the tapes have two sides and my Akai GX-4000 is a 4 track which can play them just fine. I use Audacity for sound editing so I will try to adjust the speed down to the slower rate and see if the playback sounds right. I also have access to an old Roberts tape deck which may play the slower speed 1 7/8 but I am not sure if it is in good operating condition. I will look into it this weekend.

Thank you for sharing your knowledge with me! :)
 
When dropping the speed in software the best way would be to sample at 88.2 or 96 kHz and then drop the sample rate to 44.1 or 48 kHz. (sampling at 88.2 and then dropping to 44.1 would be cleanest).

Sampling at 44.1 and halving the speed would be roughly the equivalent of sampling (at the correct speed) at 22.05 kHz - not the best!

I've seen a handful of pages selling the capstan sleeve used for 7.5 ips if you can't find yours. http://www.grandcanyontuberadio.com/capstan bushing/capstan_sleeve.htm is one that came up in Google.

A great resource for Akai is Steven Bender's Akai pages at http://slbender.exactpages.com - he has history, specs, photos etc.
 
I am considering buying a Sony TC-366 or 377 which plays at 1 7/8, 3.75 and 7.5 ips. Does anyone have any experience with these decks?

Thanks for the tip on halving the speed in software. I will give it a try. :)

Right now I am thinking that I will use the Akai for 3.75 and 7.5 ips transfers to digital and the Sony TC-377 for the 1-7/8 ips tranfers. But I will try the software approach first and see if that works.
 
I know this is some years into the future since the question was posted but here is a tip for anyone else with a similar problem.

If you have tapes speeded at 1.7/8 and your machine plays at 7.5 & 3.3/4. try obtaining another machine that plays at 3.3/4. set to record from that machine onto the 7.5 and record the 3.3.4 tape at 1.7/8 onto the 7.5, after recording at 7.5, rewind then play as normal at 3.3/4.

It works both ways, the only problem being, the quality may be well down if recording at the slower speed.

Anyone got a spare speed sleeve for a Akai 4000ds? With top nut if possible, but just the sleeve if no nut available. reasonable price and postage met.

Also seeking reel retainers for the same machine.
 
Has this machine got a selector or optional drive pulley for swapping between 50Hz and 60Hz power supplies? I remember when I first bought a TEAC 3340S many years ago the previous owner had the belt on the 60Hz pulley, (we have 240V 50 Hz here) and some of my old tapes would play at the wrong speed (20% out?) I found the pulley problem then while looking for a adjusting pot on the circuit board.

Alan.
 
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