Calibration tape

[stellavox]

Calibration tapes

Amirm,

I've responded to this before. MRL is the way to go for what I would describe as tapes with "ultimate accuracy". Problem is that all their "standard" tapes are for one speed / one equalization. If you are into this tape thaang seriously, you might want to have them make you up a "special" tape (as I have), with both 15ips NAB and IEC and for that matter 7 1/2 NAB - if you are into playing back older pre-records. Back when I asked them to do this for me they made up a tape with all the stuff I asked for, for less than the cost of two tapes.

What I suggest you need is at each speed; first a 1kHz calibration tone, then a high frequency tone to set the azimuth, then frequency sweeps - suggest two sweeps rather than one. If you want the IEC sweep, then they can put it right after the NAB sweep.

I have the Sound Technology (ST) 1500 and MRL can supply a tape that includes ST's special azimuth calibration tones along with a frequency sweep that synchs with the 1500 making playback frequency response checks a snap.

Cheers

Charles

 

[amirm]

Ouch. These things are getting more expensive by the minute!!! I was hoping all good tapes of interest are 15 ips. I suspect the commercial ones are 7.5 ips. Is that correct?

 

[tony ky ma]

Don't worry, there are a conversion table come with the tape, you can use one tape to calibrate all others with different reading, maybe not too convenience but save money
most pre recorded commercial tape in 2 track is 7.5 in/s but in 4 track with 7.5 and 3.75 both. 3.75 is the cheapest in price on Ebay but will not sound as the others
tony ma

 

[amirm]

Thanks Tony. I remember now using our frequency counter and calibrating the speed at either settings.

 

[Bruce B]

Amir.... when you get your R2R.. you can borrow any of our tapes you need.

 

[amirm]

Thank you so much Bruce. You are generous as always! It is a big relief that I can do that....

 

[c1ferrari]

Where did you find they do not match?

Micro,

I don't wish to misinform, so I'll try to obtain the relevant information for you -- if possible. A while back, Studer technician par excellence, Charlie Bolois, was aligning my A820 with fresh MRL tapes. Following the alignments, of which there were a few -lol-, I asked Charlie to thread up the TP alignment tape, which had yet to be opened.

Well, I don't profess to understand what I witnessed, other than to state my observation that the meters did not respond symetrically. Charlie noticed my consternation and opined his confidence in the MRL reference tapes.

Following the alignments, Charlie assessed my unit with his AP. As I recall, he ran a couple of full spectrum frequency sweeps, record and reproduce, for both channels, simultaneously. Charlie exclaimed, paraphrasing...They never come out this good!! The AP plot, as rendered on the laptop, was dead flat (~ +/- 0.5 dB) @ 15 ips, 1/4" tape, with the characteristic Studer bump circa 30 Hz.

I should mention that I had Charlie and John French collaborate to install and optimize a 318-series headstack on my A820.

Here are some links I hope you"ll enjoy...

http://www.youtube.com/watch?v=ygowAyGvZ1c

http://www.xtranormal.com/watch/7001905/studiotimi-meets-al-schmitt

I found this last one especially amusing

 

[tony ky ma]

Hi Sam
I agree with you the MRL & TP are not 100% the same, even all test tape will not 100% to the standard, I think the TP test tape is let your machine's setting match to their machine with the best in repro. in the two of A80 for live recording serviced with same guy and same equipments, the best sound repro is by the same machine what recorded because they have different heads, one is 317 butterfly sound better,so very detail accurate reading measurement for analog will not telling what will they sound, like vinyl's cartridges have similar same frequency respond but they all sound different, same thing happen to tape recorder too
tony ma

 

[c1ferrari]

Good morning, Tony,

Recording and reproducing on the same deck would seem optimal provided the tape path, azimuths, electronics, etc. were properly aligned.

Once I develop a dexterity, if ever -lol-, with mechanical alignments on the Studer...I will align the repro head with the TP tape for listening to TP reels. Then, realign with MRL afterwards. I have other tapes that came with tones and will probably adhere to the same sequence.

I'm curious if anyone has aligned and realigned their machine with MRL and Tape Project and noted a difference when listening to TP material?

I'd love to hear your recordings, Tony...perhaps, someday!

 

[microstrip]

Sam,

When you say the alignment for TP and MLR are not exactly the same are you referring to head azimuth or equalization levels?

 

[c1ferrari]

Sam,

When you say the alignment for TP and MLR are not exactly the same are you referring to head azimuth or equalization levels?

Hi Micro,

It was a while ago and I cannot attest to my recollection (other than my observation noted earlier), now, yet alone my apprehension of the significance and etiology of the dissimilar behavior.

Hazarding conjecture, I would say it's azimuth.

I apologize for the imprecision at the moment

 

[tony ky ma]

Good evening Sam
I am working on the repro amp of A80's modification, a tube out put, after done will start to make copy from our live recording, we bought blank tapes and reels already also need to settle the legal matter first and then will make a web site too, wait till there, won't be too long
best
tony ma

 

[flez007]

Amir - for some reason I am tending to believe that you will (or are) back to RtoR...

 

[amirm]

You would be right . It is a hard format to get into though. In the old days, I would do my own recordings so R2R had a lot of value. But today I don't care to do that so it is more challenging.

But nothing says "fun" more than those wheels turning!

 

[microstrip]

(...) But nothing says "fun" more than those wheels turning!

Surely, but some machines also inspire you also some respect.

Until recently I had owned Teac X2000, Akai 747, and several Revox's and a Studer PR99. But the day I received my first Studer A80 and pressed the play button was a different experience - the precision and solidity of the large main capstan and double roller system makes you feel you are in control of something remarkable.

 

[amirm]

My problem with the other units is the sheer size. I need a desktop machine, not a console. I guess I also don't think I will be using it a lot .

 

[naturephoto1]

My problem with the other units is the sheer size. I need a desktop machine, not a console. I guess I also don't think I will be using it a lot .

Hi Amir,

Maybe you would be interested in the project that RogerD and I are working on as a possibility. We will both ultimately have basically the same Ampex 440C/B hybrid. Because of my lack of space, rather than the console set-up that Roger has:

mine will be set-up as a vertical desk top deck in a compact aluminum case much like this:

We will be making a fair number of modifications including many caps and resistors while they can still be obtained as well as changing out some transformers.

You may want to contact Roger about what we are doing.

But, my understanding is that my machine aluminum case dimensions will be approximately 21"W X 34" H X10" D; it will weigh approximately 100 pounds.

Rich

 

[microstrip]

I raised this question of console or upright (should an A80 reel to reel be operated in the vertical?) in another forum and the general answer was that the wow and flutter performance is better in horizontal than vertical orientation for most machines, not only for the Studer.

 

[RogerD]

I raised this question of console or upright (should an A80 reel to reel be operated in the vertical?) in another forum and the general answer was that the wow and flutter performance is better in horizontal than vertical orientation for most machines, not only for the Studer.

I have seen many machines mounted vertically in recording studios. I personally favor the horizontal mode,but I think if there is any effect on perfermance,it would be negligible. Maybe I'm wrong though.

 

[naturephoto1]

I raised this question of console or upright (should an A80 reel to reel be operated in the vertical?) in another forum and the general answer was that the wow and flutter performance is better in horizontal than vertical orientation for most machines, not only for the Studer.

I suppose that that may be true. But, that would also mean that any Prosumer machine (I believe that they are almost all) in an upright design could not have wow and flutter perform as well a console orientation machine (unless it was placed horizontally). In my situation though I just do not think that I have the space to install this machine in a console orientation. In addition any machine set up in the console orientation could not be monitored as well from across the room as in a vertical orientation.

So, if true, like so many other things in life and in audio I may have to compromise a little performance to have the ability to use this or just about any other R2R machine in my system in a vertical orientation.

I have seen many machines mounted vertically in recording studios. I personally favor the horizontal mode,but I think if there is any effect on perfermance,it would be negligible. Maybe I'm wrong though.

Roger having seen photos of my room and the available space that I have has concurred that he does not believe that I could install a horizontally oriented machine and could only install a vertically oriented R2R for the available space.

In addition, a console orientation may be more convenient for sitting in front of the machine for recording as in a recording studio environment, my machine will be and is intended more for playback and only to be used for recording on occasion.

Rich