Let dream about designing a new machine!

[ironbut]

From a quick google, I stumbled across this guy. He's in Oakland but you'd have to check to see if the Ampex is there.

http://www.artichokepro.com/pages/stuff.html

[docb]

Thanks, talked to him a while ago and it is long since gone. Couple years ago I wavered over one on ebay for $99 that was in the South Bay. Lucky you, I prolly woulda asked you to pick it up...two 6' tall racks...

[ironbut]

He he,.. a couple of years ago I would've had use of a flat bed, a fork lift and a warehouse with nothing but a couple of wooden boats and a spray booth. For a six pack I probably could've gotten away without getting my fingernails dirty (or bloody).
One of those boats is for sale (or was). Check it out. My ex-boss and wife were given an award in Italy for this restoration.

http://www.portcarlingboats.com/pmehus/pmehus.htm

[glimmie]

Since reel to reel machines exist and one could be retro engineered in order to produce a new one (if such a demand arose) a newly built one off reel to reel while an elegant concept I don't see it as having a practical use.

However this does not rule out the possibility of an entirely new style tape recording device.  Along with my recent reel to reel excursions I've also investigated recording into a hi fi stereo VCR and with excellent results.  Results that perhaps exceed my TEAC A 2300 SD.  I'd like to see a purely audio recording device based on the VHS format but with perhaps 6-8 tracks.  Such a machine with on board effects like a modern digital work station and  a USB  interface for communication with digital sources would be an interesting device.

Keep in mind however that VHS HiFi is not a stationary recording medium. The audio is FM modulated to 1.3mhz (left) and 1.7mhz (right) and applied to the video heads. You aren't going to record 1.3 or 1.7mhz with stationary heads running at 0.5ips such as in VHS EP mode. Also FM recording is not the holy grail. As we know the signal quality is a product of the deviation. In VHS HiFi it is rather narrrow hence they use a DBX type compander to get around that. You have the FM video carrier at roughly 3mhz and the AM chroma at 629khz there as well so intermodulation is a serious issue. But as the frequency responce is still very flat across the audio band being recorded andf played back the companding works much better than with straight analog recording but still pumps. Then we have the achiles heel of FM video recording. The head switching. The tape is only wrapped half way around the head drum so they switch between two heads to maintain continous tape contact. this produces a strong 60hz DC offset in the recovered signal due to tension differences in the tape. So to minimize that there is usally a 60hz notch filter employes.

No, VHS HiFi really isn't HiFi by our standards here.

You know they did come up with a solution to all these issues - it's called RDAT!

[Lance Lawson]

Since reel to reel machines exist and one could be retro engineered in order to produce a new one (if such a demand arose) a newly built one off reel to reel while an elegant concept I don't see it as having a practical use.

However this does not rule out the possibility of an entirely new style tape recording device.  Along with my recent reel to reel excursions I've also investigated recording into a hi fi stereo VCR and with excellent results.  Results that perhaps exceed my TEAC A 2300 SD.  I'd like to see a purely audio recording device based on the VHS format but with perhaps 6-8 tracks.  Such a machine with on board effects like a modern digital work station and  a USB  interface for communication with digital sources would be an interesting device.

Keep in mind however that VHS HiFi is not a stationary recording medium. The audio is FM modulated to 1.3mhz (left) and 1.7mhz (right) and applied to the video heads. You aren't going to record 1.3 or 1.7mhz with stationary heads running at 0.5ips such as in VHS EP mode. Also FM recording is not the holy grail. As we know the signal quality is a product of the deviation. In VHS HiFi it is rather narrrow hence they use a DBX type compander to get around that. You have the FM video carrier at roughly 3mhz and the AM chroma at 629khz there as well so intermodulation is a serious issue. But as the frequency responce is still very flat across the audio band being recorded andf played back the companding works much better than with straight analog recording but still pumps. Then we have the achiles heel of FM video recording. The head switching. The tape is only wrapped half way around the head drum so they switch between two heads to maintain continous tape contact. this produces a strong 60hz DC offset in the recovered signal due to tension differences in the tape. So to minimize that there is usally a 60hz notch filter employes.

No, VHS HiFi really isn't HiFi by our standards here.

You know they did come up with a solution to all these issues - it's called RDAT!

When I refer to a VHS format I'm not saying that the entire audio signal chain be that of VHS format.  I'm thinking more on the lines of the tape cartridge, rotating head and transport layout.  The tape speed could run at a faster than VHS speed perhaps double giving 1 hour tape time per cartridge.  As it would not be concerned with a video signal all of the engineering could be devoted to audio only.  Considering that Hi Fi 1/8" cassettes are fairly capable devices the device I envision should be able to exceed that quite easily.

[niklasthedolphin]

Even though I meant it to deal with cassette tape deck, there are some points of view about open reel decks in this thread I started up on another community some time ago.
Please have a look:
http://www.tapeheads.net/showthread.php?t=1407

Just for fun.

"dolph"

[glimmie]

When I refer to a VHS format I'm not saying that the entire audio signal chain be that of VHS format.  I'm thinking more on the lines of the tape cartridge, rotating head and transport layout.  The tape speed could run at a faster than VHS speed perhaps double giving 1 hour tape time per cartridge.  As it would not be concerned with a video signal all of the engineering could be devoted to audio only.  Considering that Hi Fi 1/8" cassettes are fairly capable devices the device I envision should be able to exceed that quite easily.

If you keep the rotating heads you have two choices: FM analog or digital technology. The digital is superior in many ways one of which is the data can be buffered to get around the head switching problem.

Again they basically have made a format on this principal, RDAT. The Sony PCM800 is a good example. Tascam made a compatable unit as well.

[TomR]

Well, as long as we a putting forth a wish list for a new machine:

1. Great tape handling.....but easy/fast to thread. Maybe I need a whole bunch more practice, but I find the RS15XX series to be not fun to thread. It is an effort. If I am a little tired or have had an adult beverage, I tend to avoid my Technics RS1520. I don't have that problem with my Revox A77 which I use for 4 track tapes.

2. At least two speeds - 15 ips and 7.5 ips. And with a 4 track playback head.

3. Great electonics - I am OK with tubes. It would be great to have a tube wear indicator, like VTL has on one of its amps.

4. On board Dolby B circuit for playback of my 7.5 ips Dolby encoded tapes.

5. Switchable IEC/NAB equalization.

6. Of course, 2 track playback head optimized for Tape Project tapes.

[niklasthedolphin]

When I refer to a VHS format I'm not saying that the entire audio signal chain be that of VHS format.  I'm thinking more on the lines of the tape cartridge, rotating head and transport layout.  The tape speed could run at a faster than VHS speed perhaps double giving 1 hour tape time per cartridge.  As it would not be concerned with a video signal all of the engineering could be devoted to audio only.  Considering that Hi Fi 1/8" cassettes are fairly capable devices the device I envision should be able to exceed that quite easily.

If you keep the rotating heads you have two choices: FM analog or digital technology. The digital is superior in many ways one of which is the data can be buffered to get around the head switching problem.

Again they basically have made a format on this principal, RDAT. The Sony PCM800 is a good example. Tascam made a compatable unit as well.

It was another one that me suggesting anything digital in the thread I linked to.
I want to keep it stricktly analog.

"dolph"

[glimmie]

It was another one that me suggesting anything digital in the thread I linked to.
I want to keep it stricktly analog.

"dolph"

You mean a 1/2 inch cassette analog stationary head format? Just keep in mind there is not much tape length in a VHS cassettte for high linear tape speeds.

My we interest you in an El_Cassette? Remember that format?

[niklasthedolphin]

It was another one that me suggesting anything digital in the thread I linked to.
I want to keep it stricktly analog.

"dolph"

You mean a 1/2 inch cassette analog stationary head format? Just keep in mind there is not much tape length in a VHS cassettte for high linear tape speeds.

My we interest you in an El_Cassette? Remember that format?

I remember EL-Cassette.
And that's Not what I mean either.

Now; If you reread the thread I linked to and remember my nickname is the same as here, then I'm sure you will get an idea about what I mean.

"dolph"

[steveidosound]

Use of a 1/2' VHS cassette has many issues. Not much tape so no high speed. Wrong type of tape for best analog audio performance and you cant use narrower tracks and turn the tape over like a normal audio cassette. You could double the length with some sort of special auto reverse transport but it would still be very short at a speed that would give any kind of quality with analog technology. And as was pointed out you can't use normal analog technology with spinning heads. Closest would be something like VHS HiFi FM system.

My vote for a new open reel design would be something like a cross between an updated old Ampex 350 series transport and the famous little Sony 770 that used clever electromechanical technology to provide more or less constant tape tension. Something clever and simple without a lot of microprocessor controlled complex circuitry and sensors, yet providing excellent tape handling and precise speed and tension control. More Nagra than Technics if you get my drift. And as I posted earlier, tube record electronics from Bottlehead to match their playback ones, designed for state of the art heads. All in some sort of portable case please. Preferably not much bigger than say a Revox A77.

[ofajen]

So, I'd like the members to say what they'd like to see in a machine. What features and spec's are a must and what should just be options.

To start out, I think that there's no question that this would be a hand built machine so just having a nice heavy deck plate milled, motors and motor control units (of whatever design), an exchangeable headblock (or do we want that?) and a system for moving the tape (or heads) into contact we're probably already talking in the $10k neighborhood. For such a machine to be worth this kind of price, it has to be capable of a least competing with the likes of an A820 or ATR102.

I was speculating about this not long ago on another list.  For it to be worthwhile, I think it needs to offer something the Studers and ATRs don't offer: portability.

I'd start from the latest Stephens design and then try to make it even smaller and more reliable.  A 2" 16-track that weighs 50 pounds in two portable racks with a high quality companion rack console would be very handy for folks like me who have to move gear to record in better sounding places or to where certain instruments are or to where music takes place.  I'd also prefer automation for setup, i.e. a machine with built in diagnostics and automated calibration with settings for favorite tape formulations and level preferences.  Robust, built in sync capability, too.

Cheers,

Otto