Ampex 440C 1" 8trk Capstan motor

That's cool, I did not know that. I did have them re-lapped. I think they said on the chart it has 38% life left on the heads.
 
That’s great. Not that there aren’t others capable of doing the work, but John and his wife are great people and JRF is my preferred provider for evaluations and service on heads and assemblies. He’s done some amazing work for me.

Did you recap the plugin cards in the electronics at all? Do you know about the tantalum cap that should be replaced to mitigate risk of dead short failure mode and damage to the record head?
 
Yes John was nice, he did a set of 1/2" 4trk for me as well way back. So I replaced all the caps throughout the unit cards, power supply, the one Tantalum that can kill the head coil switched to a quality electrolytic. Replaced all the non-polarized caps in the transport. Motor caps.
 
Echoplex said:
Does anyone make replacement record heads now? For 440's?
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I really don’t think so…Flux was the last one I know of making new heads but I believe Greg retired. So anything out there would have to be from any existing stock. I’d check with John French and also ATR Services. There are others I’m sure…
 
All the head cables wire leads were messy so I carefully bundled everything, I did some repainting of some of the black parts. The headlock stainless steel cover was scratched so I had a new one fabricated. One power transistor was bad in the one power supply on back that needed replaced along with the large power supply caps. The only place I need to check is the power booster box behind the transport, I don't recall if I replaced that one as it has a one in there.
 
That's the disturbing issue, once the heads are worn completely these machines cannot continue to operate.
 
On the JRF website so maybe there are options.

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  • 1" 16-, 8-, or 4-track
  • 1/2" 4-track (standard or low-speed duplication mastering)
  • 1/2" or 1/4" 2-track mastering
  • 1" 2-track mastering for Studer A80, A800, J37 or C37
  • 2" 8-track (+ 9th timecode track) for Studer A800, A827, A820 Otari MTR90
  • High-speed and in-cassette duplication
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For any machine
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When it's time to replace your multitrack or mastering heads, JRF lets you choose the exact heads you want, selecting from a variety of sources and suppliers.​
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Independent Manufacturers - We carry the complete lines from a variety of independent manufacturers of replacement heads. No matter the make, model or age of your recorder, JRF has replacement heads that will bring your multitrack recorder back up to new factory spec – if not better! Give us a call for a listing of most suppliers and available models . Chances are we either have it in stock or can get it in a day or two.​
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You’d have to correspond with John French regarding what’s actually available. I’m not sure how up-to-date the website is. He and I chatted quite a bit over the phone about the current situation earlier in the year. The conversation was spurred by the difficulty we were having sourcing a replacement reproduce head for my 3M mastering machine…a 1/4” halftrack. You’d think that would be easy, but it wasn’t.

You’ve done a lot of nice work on your Ampex machine…should serve you well for a long time!
 
I'll reach out to him. Yes, thank you, it's been a multi-years long project. I hope I can keep this deck running. Bought two extra reel motors for it and misc parts.
 
I wonder if the (HF response) 440C heads were the same as the MM100/1200 1" optional headlocks? I read the electronics were the same. Basically that the C 400 sounded as fat and rich as the 1100/1200. It certainly sounds fat and rich hitting it hard at 15ips on 456 or equivalent tape. I passed on a 15trk MM100 for 850$ way back:ROFLMAO: Needed work but they all do right...
 
When you say “MM100” do you mean MM-1100? The MM-1100 is relatively solid once it’s had the all the field updates implemented, which, in a coarse sense, essentially makes it an MM-1200. It’s also beneficial to upgrade the static guides to rolling guides.

I’d have to look to see if the MM-1100 heads are later generation. I’m sure the MM-1200 heads are…pretty sure the MM-1100 heads are, but, again, I’d have to look. It’s not about “fat and rich”…they are all going to have very similar low frequency performance because of the head profile, gaps and the signal path. The difference is in the HF performance and you can see that in the specs between the AG-440B and AG-440C (at 15ips the B is +/-2dB 30Hz~18kHz, the C is +/-2dB 30Hz~25kHz).

Interesting…the MM-1100 appears to have earlier generation heads, and in fact has diminished HF performance compared to the AG-440 and AG-440B…at 15ips the MM-1100 is +/-2dB 30Hz~15kHz…and…extra interesting…same for the MM-1200…! There must be something disparate in the conditions used to gather the data, because, again, all the AG-440 and MM series machines, including the MM-1000, share the same head profile, gaps (although revised reproduce gap on the AG-440C I believe), and signal path. So maybe there is something different in the reference level standard or weighting of the test signal.

But here’s the thing to remember…specs often don’t tell the whole story, and they certainly don’t tell you how a machine actually sounds. It doesn’t represent the actual response curve, the peaks and dips…how the chain responds to the source material…the Ampex specs also don’t share the weighting that was used. Also note, while a 15kHz top-end sounds limited, the response spec frames the -2dB knee points, where a majority of other manufacturers use +/-3dB…so the Ampex specs are conservative. Also, the proof is in the pudding…if a -2dB top-end at 15kHz was a deal-breaker, why then is the MM-1200 one of the most popular and revered multitrack tape machines in history? Again, the specs don’t describe how it *sounds*…the specs give you comparative data…*sometimes*…when the data is comprehensive (provides the parameters and conditions…and most don’t do this…so I consider spec sheets carefully because usually the marketing people have a hand in what gets published).
 
All great interesting points, especially the MM1200 freq response. Oh, sorry yes MM1100/1200 16trk:oops:, speed typing is not my strong point ha! Basically the three Ampex decks I have had are 1/4 2trk C/B models, 1/2" 4trk and 1" 8trk, they all sounded fat and rich to me compared to my old Panasonic 1/4 2trk and Otari 1/2" 8trk. I don't miss those plastic, particle board boxes, actually the Panasonic had more metal than the Otari! I especially liked the 1/4" 2trk B for live stereo. From memory I think the Ampex head gap was a bit larger on that format.

I'm just glad to pair it all down and keep the 1" 8trk considering all the work and the great sound. That servo missing still makes me want to find one, I know it's unnecessary...that's just the bad completist part of me:ROFLMAO:.
 
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