This is some background and history of the Hilton Micro 75A Tom Pauer bequeathed to Pollywogs/Recyclers. It lives at Arlene Klemp’s house and she graciously schleps it out when we have visiting callers for either/both clubs.
Bill Haynes complained about having to crank Tom’s Hilton way up for Recyclers on 4/11/14, so out of an abundance of caution, 
Phil graciously grabbed the MA-150 from Ebenezer and Bill used that for the C2 and C3A dances the next day without reported problems.
I brought Tom’s Hilton to Chi-Town last Monday and had Sandie try it. She did a quick check with her computer and got good volume at a normal setting of the control. But then she 
remarked about the MA-150 that somebody had left it with the music volume cranked up unusually high, and Bill had been the last one to use it. She drew a kind of immediate conclusion that there was probably something wrong with Bill’s computer – like its volume had somehow been turned down some.
I wrote to Bill and with appropriate apology asked if that might have been the case. He replied that he had in fact checked his laptop, and that he didn’t notice anything unusual with the MA-150. I’m not sure what to make of all that.
There is one other common component, though: I think Bill used the same speaker (maybe a 2-driver Tom P special?) for all the dances. If that speaker had a problem, it might have manifested by requiring both Hiltons to be cranked up higher than usual.
I checked Tom’s Hilton out as well, and had no problem getting lots of volume out of it with a half Yak. I ran it pretty loud continuously for 45 minutes and didn’t notice any distortion or change in volume and it didn’t smell or feel unusually hot.
I don’t have a laptop I routinely use with Hiltons, and so can’t comment on how the music volume control level “feels”. I did run the same audio source (a red iRiver IFP790) at the same output setting (40 – the max) with Ray Clow’s old Micro 75, and compared to that I think I have seen what Bill saw. To get the same speaker volume, the music volume control on Tom’s Hilton had to be set considerably higher than on Ray’s, and with the controls both cranked up full I got a lot more out of Ray’s. Unfortunately, that’s not a great point of comparison since Ray’s unit has an unusual history, having been rebuilt by me. Voice levels/settings seemed fairly comparable between the two in informal testing with Tom’s old mic.
Tom’s unit has 2 places to put music audio in: one marked Tape Music on the front and one marked Monitor All on the back. I got a little more volume using the one on the back, but the music was brighter using the one on the front. I think both the “inputs” above were really designed as outputs to record dances, and sort of accidentally work as inputs. As such, it’s not surprising that they don’t work ideally, and I’ve heard that comment elsewhere including the nice hookup pdf here. Hilton even makes “boosters” to address this issue. What’s surprising is that Bill reacted as he did to a known “weak” input.
I considered building a booster transformer in, but decided not to take the liberty of doing that. Another possibility would be making a custom block (no cables) with a transformer and RCA in and out that would plug directly into the Tape Music jack, fitting tightly against the Hilton. A quick check indicates that the lid could close with it in place so it could just live there forever. Yet another is a blob containing a transformer with RCA male and females on short pigtails that would at worst just live in the black bag/case for that Hilton. I have not done neither of those (yet).
My overall take is:
- There’s nothing wrong with Tom’s Hilton. It’s an old unit whose workaround music input isn’t very sensitive and works best with a booster. We should continue to use it as we have in the past.
- We should still keep an eye on it for a couple of dances. Having a spare Hilton for those dances would be a good idea.
- It’s vaguely possible Tom’s/Polywogs/Recyclers speaker is questionable.