mitchillinois
Active member
Thank you. I was aware of the different electronics and that the 351 is preferred. It's helpful to know that the 350 electronics PSUs are external and that they are internal on the 351s.
Studios with Ampex 350/351 – U.S. & Europe
- Thread starter mitchillinois
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mitchillinois
Active member
Thanks. Yes, that's an alternative and is easier. My goaI is to find studios with the tape machines in active operation (restored, maintained, and work pretty much as they did back in the day). Using one machine at the end is definately a logistically superior approach.+1 for recording everything clean, then add ampex residue as needed in the final processing. That way you'd only depend on one machine, and also avoid problems with the very-different wear patterns that could be expected from six different 70 years old machines from across the world.
Unless, that is, you need all the processual problems and complications associated with getting those tape machines behaving in the situation. Or if you need pictures of said process for that matter.
If you really need what most of us associate with 50'es sound, you may want to consider going to optical media (film sound) and back
/Jakob E.
This is all spoken word, and the documentary uses a wide variety of audio sources. So all that matters in terms of precise sound consistency is that each voice actor's sound is consistent. They are portraying people in different places.
Optical sound is an interesting idea but we don't have any other optical sound in the documentary.
mitchillinois
Active member
Yes, a 350 will sound a bit different than a 351 and a tube Studer will sound different than they do. Fortunately, for this project, each voice actor is portraying someone in a different location, and so that's OK.
It is striking that today musicians use the pres for special effects. I'm just looking to be sonically authentic to the tine.
I used the Ampex 602 a bit and the 350 a great deal very early in my career because the radio station still used some older equipment. The 350 was built like a tank and always worked well.
The evolution of audio technology from mechanical (early recordings) to tubes to transistors to chips to software is fascinating. I am sure that no one in the 1950s, or even in 1980, foresaw software emulating the tape machines of the time.
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Barry Hufker
Well-known member
"I am sure that no one in the 1950s, or even in 1980, foresaw software emulating the tape machines of the time."
No, we always wanted something better!
No, we always wanted something better!
I have made new upgrade circuit boards for the Ampex 351. They have 20db better signal to noise and I will make them available soon. They are drop in replacements for the original boards. 70db of signal to noise, .5% distortion. They really sound great. They also provide phantom power to microphones.
Attachments
I could write a book about these machines(but I'll leave that to Deke Dickerson).
I have serviced dozens eventually designing my own PCBs for the 351(I don't sell them, only used in complete overhauls).
I designed a device that allows engineers to use 350 or 351 electronics with a 440 transport without modification to either the electronics or the transport, including the heads(currently not for sale either).
At one time I even outfitted a vehicle with all the proper period gear and traveled the country making recordings, the dream was to outfit an airstream with the gear....but that remains a dream.
But if I were embarking on the project mentioned in this posting it would be just that...outfit a RV or trailer with a well maintained machine(or 2) and period correct console staffed by an experienced tech/engineer.
In the decades I have been working on these machines I have only seen 2 machines that would be considered properly overhauled and maintained come into my shop...but nearly every machine I have seen has been advertised as such...buyer beware!
Only experienced techs should even attempt to align a 351 as you have to put your hand into the rear of the machine while trying to view the VU, the electronics have seriously high voltages present and you basically have to blindly put your hand inside the electronics with tape rolling. The possibility of a very bad day is all too real!
I would never expect to show up at a studio, even ones that properly maintain the machines(which are few) and think that all the sessions would go off without incident.
When I operated a studio and used these machines daily in sessions I ALWAYS had 2 machines ready to go as you never know when a failure is likely to occur.
I'm available for consultation and unsolicited bad advice.
Good luck and let us know how it goes.
Kevin
I have serviced dozens eventually designing my own PCBs for the 351(I don't sell them, only used in complete overhauls).
I designed a device that allows engineers to use 350 or 351 electronics with a 440 transport without modification to either the electronics or the transport, including the heads(currently not for sale either).
At one time I even outfitted a vehicle with all the proper period gear and traveled the country making recordings, the dream was to outfit an airstream with the gear....but that remains a dream.
But if I were embarking on the project mentioned in this posting it would be just that...outfit a RV or trailer with a well maintained machine(or 2) and period correct console staffed by an experienced tech/engineer.
In the decades I have been working on these machines I have only seen 2 machines that would be considered properly overhauled and maintained come into my shop...but nearly every machine I have seen has been advertised as such...buyer beware!
Only experienced techs should even attempt to align a 351 as you have to put your hand into the rear of the machine while trying to view the VU, the electronics have seriously high voltages present and you basically have to blindly put your hand inside the electronics with tape rolling. The possibility of a very bad day is all too real!
I would never expect to show up at a studio, even ones that properly maintain the machines(which are few) and think that all the sessions would go off without incident.
When I operated a studio and used these machines daily in sessions I ALWAYS had 2 machines ready to go as you never know when a failure is likely to occur.
I'm available for consultation and unsolicited bad advice.
Good luck and let us know how it goes.
Kevin
Barry Hufker
Well-known member
You know... another way to look at this project is to bring all the actors to the studio with the machine instead of hauling a machine all over the country. One studio, one machine, one microphone, one time... I realize the actors are all in different locations, but that is what transportation is for. You'll have uniformity of conditions without most of the hassle...
MidnightArrakis
Well-known member
Interesting resistors ya got there!!!
>> PCB mounting holes need to be "isolated/non-plated thru" holes
as having multiple mounting hole that are all connected to your GND
"Copper Pour" all connecting to multiple points on your chassis will
more than likely create a "Ground-Loop" somewhere. Unless, of course,
you are using Nylon standoffs!!!.....
>> I realize that your current designs are "more than dead
quiet" and all that, but.....this is an area that generally creates
problems which can be easily avoided just by using a simple
PCB-design technique. I once worked at AMPEX in Redwood City, CA
in their "PCB Design Department" back in 1980. My 2-cents.....
>> In related news.....should you ever need any AMPEX chassis
or other sheet-metal designs/replications, I can assist you in
that department.
/
I saw that too
mitchillinois
Active member
Thank you. These sound beneficial. For our project, we're looking for studios that already have vintage tube tape decks. Since we're looking for voice recordings that sound as if they were recorded back in the day, improving S/N ratio isn't a priority for this project. For nearly all other uses of a 351, a better S/N ratio would be a priority. Thanks again.
mitchillinois
Active member
Thank you. The device to solve the 350/351 electronics and 440 transport (tape heads) impedence difference sounds wonderful. I really appreciate your tip about having two machines available and will look for that in studios. I assume that any machine purchased used would have to be checked out, restored to a greater or lesser extent, the heads aligned, and properly biased irrespective of its advertised condition. That, and the challenges of traveling solo with rather large equipment, is why I am looking for studios with vintage machines in current use. The voice actors are a smaller part of the documentary's speakers/run time and are located in numerous countries and cities. Acquiring and traveling with the equipment is a good idea, but is a big endeavor given that we are recording about 15 voice actor sessions. I expect most of these to be 60-90 minute sessions (some are as brief as three sentences) with a few requiring 3 hours. For this reason, plan A is to locate studios with tube decks in current use near the actors. Again, your tip about making sure there are two decks in the studio is an excellent one. We'll be doing this in 6-12 months so as the date approaches, I may take you up on your offer of consultation and advice.
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mitchillinois
Active member
Thank you very much! A stereo 351 in current use would be perfect. Will check out Malcom Catto and Quartermass Sound Lab in London.
mitchillinois
Active member
Thanks. Yes, the documentary has been filmed and in post-production. We're adding voice actors to include deceased characters for whom we don't have interviews. So I am looking for studios with vintage machines near the voice actors. Since in the documentary, the voice actors are not together in the same location, the machines can have slightly different sounds (just as the vintage video and audio from numerous sources does). When we filmed interviews, In this respect, the audio needs are less exacting than they might be for a music album or even a spoken word album. They are closer to the audio requirements of field reports on a network newscast (though more rigorous in several ways).
I agree about the quality of 1950s recordings. Time Out was recorded in Columbia's 30th Street studio, a former church, with revered engineer Fred Plaut on the session.
I was surprised to see photos of Rudy Van Gelder using Ampex 600s and a home brew mixer to record a live Jimmy Smith album in 1956 and Sonny Rollins at the Village Vanguard in 1957. Van Gelder was famously very tuned in to room acoustics and mike placement.
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mitchillinois
Active member
Yes, ordinarily that would be much easier. When you have a small budget and are asking famous actors to work for union scale (because of the nature of the project) it's not an option. We have to make it convenient and go to them.
Historical documentaries draw on numerous film, video, and audio sources so the nature of the sound already varies a lot and need not be uniform. This is very different than in music or even a spoken word album. It's more akin to field reports on a network newscast that use different mikes and are in very different acoustic environments but are still part of the newscast (though we pay a great deal more attention to certain audio details than a newscast when we do a sound mix).
Thank you for the suggestion, which ordinarily, would help.
Check with Deke Dickerson in LA...he knows a lot of people keeping those machines alive and using them regularly
MidnightArrakis
Well-known member
>> This webpage has links to a variety of AMPEX 350, 351 and 602 schematics.....should you need them for things like repairs, troubleshooting or "just how in the heck does this thing work"? --
https://www.historyofrecording.com/Schematics.html
/
mitchillinois
Active member
Thank you for the suggestion. Will do. We will definately need a location in the L.A. area so this is very helpful.
mitchillinois
Active member
Thank you! I've visited the site over the years and appreciate you pointing out the page with schematics links. If I travel with a tape deck I'll want a spare tube kit, schematic, and soldering iron. I remember buying 12AX7s and such as a tween/early teen when tubes were being replaced by transistors but were still in common use. So that would be a touch of nostalgia. Since I want to be able to focus on directing the recording sessions, which require attention to historical and performance nuance, I am hoping to be able to use studio decks. Thanks again.
nielsk
Well-known member
I can tell your focus is on the era of tube electronics tape machines, but of interest might be the AG350.
I know (and have known) a few engineers that were actively working using these machines when they were new, and they all vastly preferred the AG350 over the tube machines.
It was the favorite of many all the way through the release of the ATR series, as the 440 transport offered no real improvement until the last version introduced a DC capstan (and the audio electronics did not sound nearly as good).
There may be some interest in your story telling of the change from tube to transistor, and how the engineers felt about it and used the equipment.
I know (and have known) a few engineers that were actively working using these machines when they were new, and they all vastly preferred the AG350 over the tube machines.
It was the favorite of many all the way through the release of the ATR series, as the 440 transport offered no real improvement until the last version introduced a DC capstan (and the audio electronics did not sound nearly as good).
There may be some interest in your story telling of the change from tube to transistor, and how the engineers felt about it and used the equipment.
mitchillinois
Active member
Thank you. This is good to know.
Yes, since the documentary is set in the WWII era I want to record voice actors with tube machines that would have been used 10-15 years after WWII. If the characters portrayed could have been interviewed in the years following the war, these are the machines that might have been used to record them.
It is helpful to know about the AG-350 should we need to use a modern tube preamp modeled after the 351's. Made for use with modern gear, this preamp will surely be low impedance/low level and wouldn't match the high impedance/high level tape heads on a 350/351 transport. However, this type of preamp may work with an AG-350 (or AG-440) transport, since my understanding is that the Ampex decks with transistor electronics have low impedance heads. If necessary, this may be an acceptable compromise since the preamps are more responsible for the vintage sound than the specific tape transport used.
Hopefully, we don't have to do these acrobatics, but if we do, I'd look further into connecting the modern 351 emulating preamp to the AG series Ampex tape heads. I don't expect it to be as simple as swapping them out. Things rarely work that way (my guess is that it might require a resistor or a pad, at minimum).
I understand that the AG-350's transistor electronics have more of a high end (to 18,000 vs to 15,000 +/- 2 db at 15 ips) and a superior S/N ratio (full track 60 vs 55 db). I like that. For our on-camera modern interviews we used top mikes and mixers. However, our voice actor recordings are different in that I want the sound to help evoke an era. So, as strange as it may seem, accuracy to that era is more important than audio quality.
Thank again for the tip about the AG-350. Will keep an eye out for AG-350s in studios as one of our plan Bs.
Yes, since the documentary is set in the WWII era I want to record voice actors with tube machines that would have been used 10-15 years after WWII. If the characters portrayed could have been interviewed in the years following the war, these are the machines that might have been used to record them.
It is helpful to know about the AG-350 should we need to use a modern tube preamp modeled after the 351's. Made for use with modern gear, this preamp will surely be low impedance/low level and wouldn't match the high impedance/high level tape heads on a 350/351 transport. However, this type of preamp may work with an AG-350 (or AG-440) transport, since my understanding is that the Ampex decks with transistor electronics have low impedance heads. If necessary, this may be an acceptable compromise since the preamps are more responsible for the vintage sound than the specific tape transport used.
Hopefully, we don't have to do these acrobatics, but if we do, I'd look further into connecting the modern 351 emulating preamp to the AG series Ampex tape heads. I don't expect it to be as simple as swapping them out. Things rarely work that way (my guess is that it might require a resistor or a pad, at minimum).
I understand that the AG-350's transistor electronics have more of a high end (to 18,000 vs to 15,000 +/- 2 db at 15 ips) and a superior S/N ratio (full track 60 vs 55 db). I like that. For our on-camera modern interviews we used top mikes and mixers. However, our voice actor recordings are different in that I want the sound to help evoke an era. So, as strange as it may seem, accuracy to that era is more important than audio quality.
Thank again for the tip about the AG-350. Will keep an eye out for AG-350s in studios as one of our plan Bs.
