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Akai X-1800SD 15ips...

thebeez85

thebeez85

¯\_(ツ)_/¯
I recently aquired my first r2r deck and am interested in giving 15ips a go....but need the larger capstan (sourced) but understand I'll need a smaller (original) pinch roller(?)


All I have is the 7.5 ips sleeve and "regular"(?) pinch roller.

Any source on the smaller pinch roller?

Should/could I get another regular one and size it down?


First post BTW on r2r and haven't posted in a loooong while
 
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Anybody know the size of the "smaller" pinch roller? I always thought it only came with the larger normal one, that'd used for 7.5ips and slower speeds...o_O
 
I think that you could calculate the diameter of the smaller pinch roller if you know the diameters of the capstan shaft and pinch roller used for operation at 7.5 IPS. The outside diameter of the capstan sleeve used for 15 IPS operation should be double the diameter of the capstan shaft used for 7.5 IPS operation since the capstan shaft rotates at the same speed for both of these tape speeds and this together with the circumference of the capstan determine the actual tape speed assuming there is no tape slippage. The diameter of the pinch roller for 15 IPS operation should therefore be equal to the diameter of the 7.5 IPS pinch roller less the outside diameter of the 15 IPS capstan sleeve.
 
dhnash said:
I think that you could calculate the diameter of the smaller pinch roller if you know the diameters of the capstan shaft and pinch roller used for operation at 7.5 IPS. The outside diameter of the capstan sleeve used for 15 IPS operation should be double the diameter of the capstan shaft used for 7.5 IPS operation since the capstan shaft rotates at the same speed for both of these tape speeds and this together with the circumference of the capstan determine the actual tape speed assuming there is no tape slippage. The diameter of the pinch roller for 15 IPS operation should therefore be equal to the diameter of the 7.5 IPS pinch roller less the outside diameter of the 15 IPS capstan sleeve.
Click to expand...

My bad, totally meant this to be about 30ips speed.


With the capstan sleeve and the speed switch set to high, I'm nearly 100% positive it runs at 15ips.

I DO know it can do 30ips, but it takes a smaller pinch wheel, so it doesn't hit the capstan and a bigger capstan sleeve.


Guess the same rule applies huh?

Also, emailed Terry and he said he could make a custom roller, just needs to know the roller size
 
In looking over the user manual quickly I did not see any references to 30 IPS capability, only 15 IPS. As far as the mechanics are concerned the same rule applies but you will probably have other issues to address to operate the unit at higher speeds than it was designed for, equalization being one of these.
 
I have the same deck. It definitely cannot play at 30 ips. Only 15 ips is possible with the other capstan sleeve, which I don't have either.

P.S. If you read the oaktreevintage link closely, you won't find anything saying that the 1800SD specifically is able to do 30 ips.
 
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Dbxdx5 is correct. You may have misinterpreted the comments "Tapes were recorded at many different speeds. All the way from a very slow 15/16 ips thru 'blazing' 30ips" and "For the best recording quality, many recordists choose the faster writing speeds of 15ips or even 30ips. This was generally reserved for recordings where the absolute best quality sonics and sound were desired." These comments only describe the use of the higher recording speeds and do not mean that the X-1800SD can operate properly at 30 IPS.

Do you just have tapes recorded at 30 IPS that you need to play or do you also intend to use the unit to record at this speed? If your interest is in obtaining the best quality sonics and sound from your X-1800SD, using it at 15 IPS is probably your best solution.
 
And also, the Akai of this era was also kludged for 15 IPS. Not really designed for high grade 15 IPS use. 7 1/2 IPS is what the X-1800 SD in good order is really optimized for. And also optimized for low bias tapes.
 
There is an accessory kit that came with the AKAI 1800SD. It has a test demonstration tape, take up reel, mics, a blank 8 track tape and additional pinch roller.

Beware of the AKAI 1800SD tape decks! They made the play engage switch (cam) with pot metal and they crack and break and you need a donor deck part to replace the part. It is located under the face plate play function. I know this first hand I have about 6 parts units. No usable cams.
 
oh wow - thanks kent and davey! :D

I had wondered if it really did 30ips or not, for scientific purposes :idea: I'll defnitely get my hands on a better deck, once money permits! It was a free gift so It'd be silly not to tinker with it, right? It was given to me and pretty much everything is in good working order,

only REAL problem is some of the reels (all used, but new tapes on the way) kinda squeak and scrape the tape when the transport is in motion. I figure that's just due to old crummy reels, correct?


edit: have to say tho, I transferred my mono revolver LP to tape at 15ips and sounded even better!
 
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"only REAL problem is some of the reels (all used, but new tapes on the way) kinda squeak and scrape the tape when the transport is in motion. I figure that's just due to old crummy reels, correct?"

That could be the cause or the position of the reel tables may need to be adjusted so the tape winds onto the reel hubs in the center of the space between the reel flanges.
 
I'm not really sure. Attached is a table listing the various types of Ampex/Quantegy tape and some information about each of them. Here is a link to a discussion about Ampex/Quantegy tapes:

http://www.tapeheads.net/showthread.php?t=13748

Also attached is a data sheet for the Quantegy 600 Series tapes.
 

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Any idea on why the left channel would be crackling/hissing intermittently?

Happens when the unit is in idle and recording...


Of course, I'm using some oooood ass tapes till my 632 tapes get in...them again, it happens when the transport is in rec or play...:confused:
 
I got the Akai GX 1900 which does 15 IPS
The Akai X2000 has a similar arrangement.
Will have a look and provide you with a measurement.
 
You could perform a mod on those one-motor Akais to get 30ips...the three-point mount of the capstan idler is THE SAME on all the dual-lever models going back to 1957 (thru til the last GX-4000D in 1986):
Get an old tube Roberts 1055; where, the capstan adaptor is a thick/threaded barrel type and: mount that unit's capstan idler into an Akai with a two-speed electrically-switched motor (the old Roberts 1055 has only a one-speed induction motor). You'll lose the 8-track's function speed on a 1800 but, with the motor set to "fast" you'll get the reels to go 30 because the different capstan bearing will be 3x the size of the one Akai supplied with the two-speed motors.
 
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