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Author Topic: Questions about two-track format, international subscription and delivery  (Read 12968 times)

Offline sound signal

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Hi,

I would like to wish all the best to everyone concerned with The Tape Project.  Here at The Sound Signal Company we have been working towards doing something similar, but with our own recordings of music by local artists here in Cyprus.  It gives us great courage to see the open reel medium flourishing, especially after the panic of 2005 when, for a while, no tape was being manufactured anywhere and it seemed likely that no more would ever be manufactured.  That would leave us with several Revoxes and a couple of Nagra IV's we couldn't use, and force us to feed the output from our lovely Schoeps mikes into digital recorders...

I would like to subscribe to The Tape Project and would appreciate some clarification.  My apologies if the questions have been answered elsewhere, I have searched but have not been able to find the answers.  The first question is a technical one, the others are about international deliveries.

First off, I understand that The Tape Project releases on 1/4" tape recorded at 15ips in two-track format with IEC equalisation (35uS).  But there are two 1/4" two-track formats - the more consumer-oriented one with a 2mm track separation (so the tracks could be used separately for mono without crosstalk) and the wide-track stereo format with a 0.75mm track separation.  I suspect The Tape Project uses the former but would appreciate confirmation.

Second, the selective subscription for international subscribers is rated at $1500 rather than $1200.  Is that to cover the difference in shipping costs?

I also understand that international deliveries are sent via the United States Postal Service.  Is the type of service used one which provides a possibility of tracking the package?

Lastly, if anyone would like tips on how to make great recordings with a Revox G36, A700 or B77, or a Nagra IV, do ask, I would be more than happy to help.  I also have experience of modifying all these to IEC eq for both recording and playback.  I realised since the 1980's that IEC eq is quite preferable to NAB and we standardised on it here from the beginning.  It was, after all, the standard in European and British studios for decades so it wasn't an exotic choice.  It's just that most Revoxes were sold to domestic consumers so most, including ours, were built with NAB, though they could be ordered with IEC.  Also most Nagra IV's sold in the States feature NAB recording preamps.  It's a bitch to modify them to IEC, though it can be done.  We got lucky and found some IEC recording preamp cards which saved us a lot of soldering...

I beg to differ with the idea that NAB is better for 7 1/2ips though - I prefer IEC for the lower speed too.  But I concede that is a much closer thing at 7 1/2ips, and much more a matter of personal preference or the music to be recorded, than at 15ips where the NAB standard is really compromised.  So if anyone needs help modifying the EQ standard of their Revox or Nagra, do let me know which machine you have and what you want to do and I'll do my best to try and help.

Sorry for the long post.  I am just overjoyed to see a vibrant open reel community beginning to form.  I have loved this medium since I got my first very secondhand Revox G36 as a teenager in the mid 80's...

With best regards,
George Karaolides
Nicosia, Cyprus

Offline ironbut

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Hi George, welcome to the forum. I think that your questions regarding shipping/subscriptions are best left to Doc, Michael or Paul and I'm sure that you'll have plenty of questions regarding your experience changing the eq.
Personally, I'd be interested in hearing what types of music you've been recording and your preferred set up ( Mic patterns/set up, mic pre's, venue types etc). There's a few of us here that do amateur recordings and I'm alway interested to hear what other folks have come up with.
steve koto
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Offline mstcraig

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Welcome George. I make recordings of primarily local jazz music on a ReVox B-77II. If you have tips, tricks or mods for this machine, I'm all ears!! I also wonder if you know if it is possible to have a machine with internal switchable IEC/NAB EQ? This would allow me to play tapes I have already made in NAB, and then to switch to IEC to hear the Tape Project material.  Anyway, looking forward to what you have to offer all us ReVox users. Thanks, Craig
Craig Sypnier
(Magnepan, VPI, Sumiko, Shure,
Belles Research, ReVox (A-77 and B-77), Scully 280-B, Teac A-2300SD, Nordost)

Offline sound signal

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Hi Steve and Craig,

Thanks for the warm welcome!

Craig, I'm glad to see you're using the B77 Mk.II at the sharp end.  Don't let anyone look down their noses at you for using a Revox 77 series machine for live recordings, rather than heavier metal.  The legendary TAS-listed BIS LP "La Spagna" with Gregorio Paniagua was recorded on an A77 at 15ips with a pair of Sennheiser mikes and I've never heard anyone complain about the sound quality of that.  Oh, and they used 468 tape too.  And IEC eq...

To get the best out of the B77 Mk. II, I aligned it for my favourite 468 tape (another instance, like the IEC eq, where I totally agree with the Project guys - I love 468) so that 100mV p-p (35mV RMS) at the record amp inputs gives 0VU on the meters and 355nW/m on the tape.  The machine has more than sufficient headroom at 15ips with 468 tape (or other modern studio tapes) to let you use 355nW/m as your reference.  The Revox recommended setting of 250nW/m takes into account lower-spec tapes and low-speed machines and is far too conservative for 468 at 15ips.  I set up a 4dB overbias drop-off at 10kHz at 0dB.  Yes, there's enough headroom in the machine and the tape to run the 10kHz bias alignment at 355nW/m, isn't that great?  Good alignment gets you the most bang for your buck, believe me.  I used an MRL calibration tape, part no. 21J403.

As far as mods go, I like to keep them as minimal and as reversible as possible.  For the B77, it's very easy to make up an appropriate shorting plug to fit into the input preamp circuit board connector. This will let you feed the inputs straight into the record amp, which only needs 35mV RMS for 0vU as per my alignment - any line source can feed that.  You can even make it so you can plug your line source into the front panel mike jacks, which are much handier on location than the rear panel phonos.  You no longer have the mike preamp, line preamp, or recording level controls in circuit, so your source needs to have adjustable level, but the VU meters are still in circuit.

We set level by feeding the Revoxes from the adjustable headphone output of the nifty little Schoeps VMS-5U mike M/S matrix/preamp.  As a benefit, this lets us set level for both Revoxes at the same time (you need two machines when you're recording live).  And of course if you need to take your machine back to original, all you need to do is pull the plugs out and slot in the preamp card. I don't remember the part number for the connectors or the numbers of the pins you need to short together, but if you're interested drop me a personal message and I'll have a look.

As an aside, you can pull off a similar trick with the Nagra IV by feeding your source into the "External Noise Reduction" input rather than the line input.  And the Ext. NR input is a voltage input rather than a current input, so no series resistors needed in the connector. Just don't plug that cable into the line input or damage may result - I put some blanking caps on our machines' line input connectors.

As far as switchable NAB/IEC playback EQ is concerned, it shouldn't be too difficult to make a small mod for that (but it will be a pain to have to open the machine to switch...)  Let me have a look at the manual, PM me and I'll get back to you.

Now to modify the recording EQ, if you've got a 15ips NAB B77, is another matter.  To modify from NAB to IEC, it's easier to modify a record amp board from a low-speed NAB machine.  Thankfully there's no shortage of those boards on eBay or elsewhre from people who break unrepairable Revoxes for parts.  If you need that done too, let me know.

Thanks Steve for your question about our recordings.  We recorded chamber music and small-ensemble classical in a fairly "dead" underground venue.  We used an M/S setup with a Schoeps MK41 supercardioid capsule as the M mike an MK8 as the S mike.  We used a Schoeps active Y-cable and M/S hanger to give a very compact and discreet cable-hung stereo mike.  We ended up hanging it about 2.5m above the floor, 2m away from the centre of the ensemble, in a room with about 4m ceiling height.  The active cable fed a Schoeps VMS5U preamp/MS matrix, and that fed directly into the recording amp of the Revoxes from its headphone output as described above. We recorded at 15ips with IEC eq on 468 tape.  All cable besides the Schoeps active cable was Van den Hul The Patchway B5.

Hope the above is of use.

With best regards,
« Last Edit: November 02, 2008, 08:33:08 AM by sound signal »
George Karaolides
Nicosia, Cyprus

Offline Studer Fool

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WOW!  Welcome George Karaolides!
Very much enjoyed and appreciate your postings here.  The recording setup information in particular.  I look forward to your future posts (I hope for even further description of your recording sessions).  Back in the seventies Schoeps mics where revered (purportedly the sound quality was due to their being transfomerless - something which I cautiously question).  The url pointers you provide to their M/S setups reveal a VERY attractive arrangement for 2-channel recording.  I wonder what the approximate ball park cost structure is for such a setup?

Also do you record the two channel stereo or the M & S signals to tape???

Thanks so much!
cdw
Christopher D. Wait
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Offline sound signal

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Hi Christopher,

Thanks for the good word, it's welcome to be appreciated.

As to the Schoeps cost, these were the ex-works Schoeps prices when I bought the Schoeps stuff in February 2006.  Thet gave me a 5% discount for payment in advance, and charged me 16% VAT because I'm in the EU.

MK 8g               688,00
MK 41g               573,00
VMS5U            1.377,00
KCY 250/0Ig            474,00
HSGMSC               166,00
KS 2 I                 60,00
KS 5 I                 60,00
KS 10 I                 70,00
WMS                 20,00
                  ---------
            Total   3.488,00

3.5k Euros seemed like a lot of money to me until I realised that I had more than that invested in phono cartridges.  Now all those can do is fill up a drawer, since I can only listen to one turntable at a time. With mikes you can keep making new recordings, so long as you can keep buying tape.  The more recordings you make, the less the cost of the mikes matters, and the more the quality does. These only cost about fifty hours' worth of SM468 at 15ips, are great to use and sound fine, so I think they're good value.

Here's a run down of the above items: the KCY is the active Y-cable you need to hang a pair of M/S capsules off the HGMSC hanger.  The KS cables are the active cables which can extend to a maximum of 20 metres. Having lengths of 2m, 5m and 10M means that I can also connect them together if I need a length of 12m, 15m or 17m. I can feel the purists shuddering from here but let me tell you, there's no reality check more brutal than a live recording setup to put purism into perspective. The facility to easily and quickly set the equipment at the right spot makes much more difference to getting a good recording (or any recording at all) than an additional Binder connector in series.  The VMS5U preamp can feed up to 200m of line-level balanced cable but we generally had it close to the recorders so we could tweak the gain and set recording level (we're setting level to both recorders from its headphone output, bypassing the record amps, remember).

You're right, this is a very attractive setup for stereo recording on location.  The whole thing, cables and all, fits in the side pocket of the Portabrace bag for one of the Nagras.  So even if we need to take two recorders, the whole setup can be carried by two guys shouldering two Nagras in Portabraces and lugging a sports bag full of recording tape and gaffa tape.  As for lugging a pair of Studer A80's to a location, I don't know. We ended up lugging two Revox B77's to most events because of silly problems (now solved) with the Nagras. I don't mind admitting that the novelty appeal of lugging two twenty-kilo recorders about soon wore off.  But at least the rest of the setup was easy to carry...

I record stereo to tape, not M/S, for several reasons.  For one, I'd need another matrix to monitor off tape when recording. Recording stereo means I don't need it to buy or build yet another piece of equipment which I will then have to lug to a location with all the other stuff.  For another, I don' t think recoding M/S instead of stereo has much to offer. It's commonly said that you can tweak M/S balance to alter the stereo perspective after recording, but I don't think that's very useful.  There's actually a fairly narrow range over which you get correct stereo perspective.  It's embarrassingly easy to find this setting. In fact I'm too embarrassed to tell you how I do it in public, PM me and I'll let you know. For a given pair of capsules you can pre-set it and leave it pretty much untouched, so there's no need to record M/S and set the balance later.  A third reason I don't record M/S is that you then need to pass the signal through the matrix a second time for mastering. That is, of course, additional processing and totally unacceptable to an audio purist (having returned from the horrors of the location to the safety of the listening room with a useful tape, I can afford to be a purist once more).
« Last Edit: October 31, 2008, 11:40:28 AM by sound signal »
George Karaolides
Nicosia, Cyprus

Offline ironbut

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Wow! It took me a while to realize you were talking Euros. After seeing the numbers I flew off on a web search that I could've avoided if I just read the next sentence. I should've remembered that I've been lusting after the Collette (Mk4) since before 2006. I've since lowered my sights on some pretty nice alternatives. The new Senn MKH8040 is a pretty promising active. I've listened to a number of files of the card and they sound pretty darn nice. I haven't gotten around to listening to the 8020 (omni) but lots of folks really love it. That could be the flavor of the month since they're pretty new ( I seem to recall that they were introduced at the 2007 CES). Of course, with the little experience I have with mic set up,.. (in my best Gollum voice) "ironbut doesn't deserve such nice microphones, he does not!"
steve koto
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Offline Ben

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We want it back from ironbut. don't we ... Like you, I remember mic's are the life
of a studio, they are a investment that pays you back with every great voice.
Now great voices, they are harder to find...   
PS. The extra costs from $1200 to $1500 are for extra shipping and overhead exporting out of the USA. Even Canada has to pay that.
PS... I want the US $ to go down ... I can buy more STUFF from the USA.
« Last Edit: October 31, 2008, 09:41:28 PM by Ben »
Set 45,Open baffle speakers,Otari 5050,,Pioneer DV-79AVi DVD/CD/SCAD player

Offline Studer Fool

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Re: Questions about two-track format, international subscription and delivery
« Reply #8 on: November 01, 2008, 10:47:33 AM »
Another terrific post, thanks George!

Looking back to your first post I see that your questions have not been answered.  Sadly, as to the shipping questions I can't really help.  BUT, I did recall a post from Paul Stubblebine (Managing Director, The TapeProject) about the guard band choice that was made (2mm).  It took a little searching but I found the posting at:
http://www.tapeproject.com/smf/index.php/topic,119.msg507.html#msg507

The rational provided therein being that the extra separation is more valued than the small trade-off in signal-to-noise.

Of interest to Studer fools is that as the A80/RC (it appears to me anyway [I am not an expert]) was the more common and popular machine for "butterfly" heads which provide the .75mm guard band, is that it also included circuitry for electronic cross-talk cancellation, unlike the A80-VU.

I would expect your Nagras to be 2mm guard band as they were so often used in film work where a center pilot tone is desired.  But I don't really know but perhaps they could be ordered with .75?  My impression is that most consumer and Revox machines here in the US are 2mm.  Are yours?

Anyway it's an intersting subject.

cdw
Christopher D. Wait
Charter Subscriber SN# 026
Studer A80-VU & Studer A80-RC (and Doc's lovingly modified Ampex 934 with Seduction Tape Head Preamp Combo!)

Offline sound signal

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Re: Questions about two-track format, international subscription and delivery
« Reply #9 on: November 01, 2008, 06:58:58 PM »
Hi Steve, I have no doubt that the Sennheiser MKH 8000 series are great mikes.  But what I like most about the Schoeps system is that it's so modular and interchangeable.  For example, to turn my existing setup into a boundary layer M/S setup all I have to add is the BLM 3g boundary layer capsule and the MS-BLM clamp. It would use the MK8 and practically all the other Schoeps items I already have, saving me money.  I know of no other manufacturer whose system is this versatile.  I stand to be corrected of course, and I have no personal interest in promoting Schoeps; I'm just bouncing my ideas off the rest of the forum, I hope to get feedback from people who've tried similar things or had similar ideas.

Christopher, thanks for the good word once again.  I expected it would be 2mm guard band, I just wanted confirmation.  This is the "consumer" 2-track format where it's expected that it should also be possible to make a mono recording on track one (upper) and reverse the reels to get double the playing time - this was the 1950's two-track mono standard.  It's also possible to make a mono recording on track 1 and a totally unrelated second mono recording on track 2.  Or indeed do "sound-on-sound", mixing an existing recording on one track with a mike or line input to record onto the other track.  The Revoxes, and most other consumer/semi-pro machines had to be able to do all this - this was what the customer expected. They needed the 2mm guard band, which was the 2-track standard since the mono days of the 1950's, because crosstalk is unacceptable for all these applications.

The .75mm guard band is a pure stereo standard.  It can't be used where one wants to record mono on one track and then flip the reels and record on the other track coming back, or for two separate mono recordings on a tape, or for sound-on-sound, because there's too much cross-talk for uncorrelated signals.  It evolved in Europe in the 1960's as a high-quality professional stereo standard. It offers about 1db in dynamic range from the wider track width, giving up a bit of crosstalk because of the narrower guard band.  But in those days, the stereo tapes they made would only be used to either make stereo LP records, or for stereo FM broadcasts.  You can't get much more than 20dB channel separation with either of these media so the little bit of extra crosstalk on the tape didn't matter.  But the saving of a dB for every generation of copying did.

Now with the Nagras, indeed the 2mm guard band came in handy for a pilot tone track when they made the first stereo Nagra, the IV-S, in 1970, but that was just a handy coincidence - nobody had thought of stereo machines with pilot tone tracks in the 1950's when the standard was introduced. The original reason behind the wide guard band was the fact that it was a two-track mono system and crosstalk from the other track coming backwards would be unacceptable. 

The Nagra IV-SL pilot tone version came with the 2mm guard band.  The non-pilot, plain stereo IV-S, came with 0.75mm guard band.  When the SMPTE time code Nagra IV-STC came out in the 1980's it, of course, also had to accommodate the timecode track in the 2mm guard band like the IV-SL did with the pilot tone track. Indeed the IV-SL and IV-STC can be converted from timecode to pilot and vice versa by introducing the appropriate electronics modules (it's easier to convert an IV-STC to pilot than an IV-SL to timecode, though).

Now as fas as compatibility is concerned, playing a wide-track (0.75mm) guard band tape on a narrow-track (2mm guard band) machine would give bass boost because of "fringing effect" - the head can pick up low frequencies recorded outside of track more easily than highs.  A narrow-track tape played on a wide-track head shows no fringing effect - the whole track is captured by the head at all frequencies.  That's why I would expect pre-recorded two-track tapes to have 2mm guard bands. The Studer butterfly-head crowd would get as flat a response from them as would all the rest of us, complain though they might about the 1dB of wasted dynamic range.

In the meantime, speaking of pilot tone or timecode, who else has realised that, recording pilot or timecode, and using a machine with a self-resolver for playback, can get you speed accuracy within 0.001% of when the recording was made - irrespective of tape tension or stretch, or machine speed tolerances?  How's that for pitch accuracy, and - what is it the audiophiles call it? PRaT?

With best regards,
« Last Edit: November 01, 2008, 07:09:12 PM by sound signal »
George Karaolides
Nicosia, Cyprus

Offline mstcraig

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Re: Questions about two-track format, international subscription and delivery
« Reply #10 on: November 01, 2008, 11:39:57 PM »
I sent you a private company email a couple of days ago George, per your previous request. Did you get it? If so, please respond. Craig
Craig Sypnier
(Magnepan, VPI, Sumiko, Shure,
Belles Research, ReVox (A-77 and B-77), Scully 280-B, Teac A-2300SD, Nordost)

Offline sound signal

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Re: Questions about two-track format, international subscription and delivery
« Reply #11 on: November 02, 2008, 08:25:15 AM »
Hi Craig,

Sorry for the delay in responding to your message. You should be getting a reply soon.

With best regards,
George Karaolides
Nicosia, Cyprus

Offline mstcraig

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Re: Questions about two-track format, international subscription and delivery
« Reply #12 on: November 02, 2008, 06:34:43 PM »
Thanks for your reply George. Just one last question. Can I assume, once the preamp card is removed, I can then plug my line level external microphone preamp signals into the front panel mic inputs, as was previously suggested? If not, what further do I need to do to be able to do this? Craig
Craig Sypnier
(Magnepan, VPI, Sumiko, Shure,
Belles Research, ReVox (A-77 and B-77), Scully 280-B, Teac A-2300SD, Nordost)

Offline sound signal

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Re: Questions about two-track format, international subscription and delivery
« Reply #13 on: November 03, 2008, 06:38:40 AM »
Hi Craig,

Once the input preamp card is removed and a shorting plug installed as described, all inputs are line level.  My reverence level alignment is 100mV peak = 0dB VU = 355nW/m on the tape.  So the source should be able to provide this level.  To use the front panel jacks, set the input selectors to either Mic Hi or Mic Lo (it no longer makes a difference which).  To set recording level, your source should have some kind of level control.

With best regards,
George Karaolides
Nicosia, Cyprus

Offline mstcraig

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Re: Questions about two-track format, international subscription and delivery
« Reply #14 on: November 03, 2008, 01:55:12 PM »
Assuming nothing explodes (!), I'll try this method for my next recording projects which are planned for December. I'll let you know how I do. Thanks again George, Craig
Craig Sypnier
(Magnepan, VPI, Sumiko, Shure,
Belles Research, ReVox (A-77 and B-77), Scully 280-B, Teac A-2300SD, Nordost)