Hi Richard,
Wow! You have no idea what it means for a little guy like me to contribute to this forum!
First, just a very quick background. Although I was born and brought up in the U.S., I spent all of my adult and professional life in India (I am of Indian origin).
I used to work in the recording studio of the Gramophone Company of India. It used to be a wholly owned subsidiary of the GC of UK. Later it became independent.
GC of India has a tape archive with acetates starting from around 1955. They are almost entirely EMI tapes and are in excellent condition. There’s no problem of brittleness and they play fine on A80’s and 807’s.

Now I work independently, usually with smaller archives or individual collections. The name brand tapes that I get, e.g. Scotch 111 or 141, usually play fine on my A807. However, given the tropical climate in India and the lack of maintenance of the tapes, warping is a frequent problem.
A few years ago, I inherited a dozen Lafayette brand tapes from my uncle. The tapes were purchased in 1960 and recorded between 1961 to 1965. 
These tapes are mostly brittle. Instead of A807, for most of these tapes I had to use an Akai GX-4000D quarter track deck to play half track recordings. Yes, I know I broke every rule in the book but I couldn't think of any other way.
Interestingly, for some of these tapes played on the Akai, I got a better playback from tracks 2 and 3 compared to tracks 1 and 4. Of course, I had to reverse them on my DAW.
A few years ago I got an acetate similar to your Vermont tape. I actually had to unwind several hundred feet of tape from the reel, somehow thread the tape onto my Akai without any reels on either side, and hold my index finger softly against the playback head while playing.
So, basically, the brittle acetates that I've encountered are due to lack of maintenance or a cheap brand of tape.
Coming back to Dave's original post, I was thinking to myself when I first read it that it might be nearly impossible to find a machine that can satisfy all of his conditions. But, then, I don't have any experience with the ATR 100 or APR-5000.

Best wishes,
Abhi (short for Abhimonyu)

Abhimonyu DebAudio Consultant and Digitization Specialist

    On Saturday, 20 November, 2021, 09:53:59 pm IST, Richard L. Hess <[log in to unmask]> wrote:  
 Hi, Abbimonyu,

This issue comes up in regard to many different machines. When I had my 
A80s, I used them for acetate tapes on a regular basis. I haven't used 
an A807 for a long time (as I preferred the A810 over the A807 for many 
reasons, and the A80 over the A810).

In many respects, I think that the Sony APR-5000 is the gentlest of the 
list I posted. On the  other hand, I had no bad feedback from the two 
A807s (refurbished by Roger Ginsley) that were sold into an archiving 
project in Pakistan to use alongside their Tascam BR-20s (which I did 
not suggest for the current project because many versions were not made 
with power supply voltage selection).

However, to answer Tim Gillette's rephrasing of the question, we might 
consider machines that start the capstan motor when going into play so 
you are not banging the stopped tape into the full-speed capstan. The 
Sony APR-5000 works that way and mutes the audio for a short period of 
time at startup.

You weren't missing something and it is good that you posted. Perhaps I 
didn't provide enough weight to that criteria.

I'd be interested in hearing more about the fragile acetate tapes that 
you encounter as I've been surprised at how well the Scotch 111 and 
Audio Devices acetate tapes have held up. I've even been pleased with 
the paper tapes I've transferred as well. The only really fragile 
acetate tape I've come across was one that sat behind a wood stove 
through several Vermont winters. One face was welded together and broke 
on ever rotation of the supply reel.

The one thing that seems to fail for me are splices onto paper leader. I 
have to remake all those splices after baking in many instances, but 
that's with back-coated polyester tapes.



On 2021-11-19 8:41 p.m., Abhimonyu Deb wrote:
> Given the notable list of people who have replied so far, normally I would keep my mouth shut.
> However, I do think everyone is missing an important point.
> Dave mentions that the machine should be able to play fragile acetate tapes. The A80’s, 807’s and Otari 5050’s that I’ve worked with would fail miserably here unless I’m missing something.
> Abhimonyu Deb
> On Saturday, November 20, 2021, 6:42 AM, James Perrett <[log in to unmask]> wrote:
> On Sat, 20 Nov 2021 at 00:55, Richard L. Hess <[log in to unmask]>
> wrote:
>> Long ago, a company I think called
>> "DarkLab" in Germany made EIA to DIN adapters out of plastic.
> They still make them and sell them on Ebay. I bought some a few months ago
> but haven't used them yet.
> James.

Richard L. Hess                  email: [log in to unmask]
Aurora, Ontario, Canada                            647 479 2800
Track Format - Speed - Equalization - Azimuth - Noise Reduction
Quality tape transfers -- even from hard-to-play tapes.