Acquiring Ampex 102

awsmone

Well-Known Member
Apr 6, 2014
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Canberra Australia
I have the opportunity to acquire a full functioning Ampex 102

This is pretty rare in Australia

It comes with 1/2 heads which I intend to use for recording

I was planning on fitting 1/4 inch heads for prerecorded tapes playback

Will there be any issue swapping them over?

I will need to buy some calibration tapes for the two heads

Someone had mentioned a good tape Repro pre at reasonable price was it from De Havilland ?.

Any other tips and tricks be grateful to receive

I have about forty recordings already live of jazz in storage

Thx

A
 

tapepath

Well-Known Member
Feb 19, 2014
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Congratulations on the Ampex 102. Matching the tape playback head characteristics to the electronics is very important to the final sound. Do you know which heads you're going to use?
I've been buying 2-track and 4-track calibration tapes from a supplier in Denmark who is on eBay his username is: nielsfup2010. He will make a tape of whatever test frequencies you want at whatever flux density you require. There's also Magnetic Reference Library which have produced reference test tapes for decades, they can be found online.
 

kodomo

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Apr 26, 2017
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I recently bought an ATR-102 too. I ordered the parts from ATR Services along the calibration tape. They get the tapes form Magnetic Reference Lab (MRL).

Why look for a tape repro, start with stock electronics, that is one thing ATR-102 is well known for. Further than that, there is always the Aria system built for ATR 102, or famous bottlehead pre or the doshi tape pre too which is well regarded in this forum.
 

Bruce B

WBF Founding Member, Pro Audio Production Member
Apr 25, 2010
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I recently bought an ATR-102 too. I ordered the parts from ATR Services along the calibration tape. They get the tapes form Magnetic Reference Lab (MRL).

Why look for a tape repro, start with stock electronics, that is one thing ATR-102 is well known for. Further than that, there is always the Aria system built for ATR 102, or famous bottlehead pre or the doshi tape pre too which is well regarded in this forum.

I did not like the Aria system on my ATR-102. I felt it took away all the characteristics of what we listen to tape for in the first place. Made it sound sterile and digital.
 

awsmone

Well-Known Member
Apr 6, 2014
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Canberra Australia
I recently bought an ATR-102 too. I ordered the parts from ATR Services along the calibration tape. They get the tapes form Magnetic Reference Lab (MRL).

Why look for a tape repro, start with stock electronics, that is one thing ATR-102 is well known for. Further than that, there is always the Aria system built for ATR 102, or famous bottlehead pre or the doshi tape pre too which is well regarded in this forum.

Thanks that’s a big help

I will start with Stock and see how I go

Are you running 1/4 Stock heads ?

What calibrations are you using for prerecorded tapes eg opus etc
 

kodomo

Well-Known Member
Apr 26, 2017
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Thanks that’s a big help

I will start with Stock and see how I go

Are you running 1/4 Stock heads ?

What calibrations are you using for prerecorded tapes eg opus etc

You use the calibration tape in according to what eq the tape you will listen was printed with. If it is a 1/4" (tape width) 15ips (tape speed) with NAB (tape eq), and 355 nWb/m (reference fluxivity), than you will use 1/4" 15ips NAB calibration tape with 355 nWb/m for a perfect calibration. Generally you can specify which EQ you prefer to the sellers.

So if you have one calibration tape, or do not want to calibrate every time you change a tape, there are two choices. One is buying the prerecorded tapes according to your choice of calibration (for ex. 1/4" 15ips, NAB, 355 nWb/m). Two, there is a set of 4-Speed PADNET boards. (The PADNET is the front end of the audio board. Remove the card and note that it can be separated in two, with the front half being for EQ control and the back end being the amplifiers) ATR Service makes this exchange for 600 usd and then you can have dual eq ATR 102 and just choose whichever you want to use.

I am running the stock 1/4" heads but I bought a mastering grade 1/2" capstan, a new timer tachometer, new lifter sleeves and new 1/4" bearings/tape guide from ATR Services. As I live thousands of miles from a tape tech, I will be changing them myself with the help of ATR Services and the service manual.
 

Edward Pong

Industry Expert
Jun 24, 2013
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Locust Hill, Ontario
You use the calibration tape in according to what eq the tape you will listen was printed with. If it is a 1/4" (tape width) 15ips (tape speed) with NAB (tape eq), and 355 nWb/m (reference fluxivity), than you will use 1/4" 15ips NAB calibration tape with 355 nWb/m for a perfect calibration. Generally you can specify which EQ you prefer to the sellers.

So if you have one calibration tape, or do not want to calibrate every time you change a tape, there are two choices. One is buying the prerecorded tapes according to your choice of calibration (for ex. 1/4" 15ips, NAB, 355 nWb/m).

Here is one fact, I'm not sure if everyone understands about the calibration tapes: You really only need 2 tapes. 1 for NAB & 1 for CCIR - regardless of the recorded level...

If the calibration tape is a 250 nW/m tape, you can use it to calibrate for 396 nW/m - just set the meter to read -4 when the 250 tone is playing & you've set the deck to 396 nW/m, since there is 4 db difference between 250 & 396. (Now your meters reading 0 VU is 396 nW/m)

Similarly, to set 396 on a 355 nW/m tape, you would set the meter to read -1 db

By doing this calibration, your meters will be reading the correct levels for the tape you're playing... otherwise, the meter reading is really not telling you anything...

Hope this helps to clarify some of the mystery (confusion) of different recording levels in tapes.

In other words, a tape recorded at 396 nW/m has more than 2x the dynamic range of a tape recorded at 250 nW/m... it's not in the absolute loudness that's important, but you will hear much more low level detail (transparency) as the very low signals have more resolution...

Ed
 

awsmone

Well-Known Member
Apr 6, 2014
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Canberra Australia
Thanks Ed
Great explanation
So if I set for 355 at -1 then 396 will be Zero?
 

astrotoy

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May 24, 2010
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Congrats! I have two of them. Not quite sure I understand your situation. I think you have a 1/2" head block with stereo heads to record and play 1/2" 2 track tapes, and want a 1/4" headblock to play prerecorded 1/4" 2 track tapes. Getting a second head block is straightforward. You can buy a new one from ATR Services or get one on the used market. They do come up from time to time. You also need a set of tape guides to swap, they normally come with the headblocks. I have both sizes for both my machines. It takes me about 1-2 minutes to change over, and I am not that fast at it.

If instead you want to play 4 track stereo tapes (like the old commercial 7.5ips tapes) then you will need to add a playback head to the 1/4" headblock. I had Greg Orton of Flux Magnetics install one of his heads into one of my 1/4" headblocks - there is room for four heads in the block. He also installed a small switch to allow me to go from 4 track to 2 track playback.

Good idea to start with the stock Ampex electronics. They are quite fine. You can always upgrade later.

If you are not mechanically/electronically inclined, the manual is pretty dense. I found it very helpful to have a top flight tech to service my machines when necessary and also to ask questions. For recording, the manual was done before any of the really hot tapes were being produced.

Larry
 

awsmone

Well-Known Member
Apr 6, 2014
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Canberra Australia
Thanks Larry

The tape path changes was the thing I wasn’t sure about....

And yes you understand exactly what I am trying to achieve
 

awsmone

Well-Known Member
Apr 6, 2014
1,616
513
435
Canberra Australia
Thanks for all the feedback it’s really helped crystallise my concepts
I have sent ATR Services an email today about headblocks, and will order the calibration tapes once I get an answer on heads
 

Edward Pong

Industry Expert
Jun 24, 2013
386
195
348
Locust Hill, Ontario
Thanks Ed
Great explanation
So if I set for 355 at -1 then 396 will be Zero?

if you use a 355 level calibration tape, set the meter to read -1, then 0 VU will be 396... YES

On my tapes, I record 25 sec of 396 nW/m, 1 KHz tone at the beginning, so you can use this to do the calibration, without using a separate calibration tape. Of course, if you want to calibrate the 10K, you will need a calibration tape...

Ed
 
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