HPM 100 ribbon tweeters [Archive] - Audio & Video Forums

PDA

View Full Version : HPM 100 ribbon tweeters



jjp735i
04-28-2008, 05:26 AM
I noticed I don't hear anything coming from my ribbon tweeters. I have a pair of Realistic Super Tweeters hooked up, sitting on top, which I think are one great tweeter. I would like to remove the ribbon and put the super tweeter in it's place. I hooked one up to the ribbon wires and I get no sound. Can I assume the crossover is bad or is it run differently. I was just going to run the super tweeters form the main wire and use the built in crossover from the super tweeters case. I was also thinking if I could split the wire going to the cone tweeter and use that.. I don't want to blow out anything on the crossover.


Thanks, jjp

Jimmy C
04-28-2008, 07:17 AM
I noticed I don't hear anything coming from my ribbon tweeters. I have a pair of Realistic Super Tweeters hooked up, sitting on top, which I think are one great tweeter. I would like to remove the ribbon and put the super tweeter in it's place. I hooked one up to the ribbon wires and I get no sound. Can I assume the crossover is bad or is it run differently. I was just going to run the super tweeters form the main wire and use the built in crossover from the super tweeters case. I was also thinking if I could split the wire going to the cone tweeter and use that.. I don't want to blow out anything on the crossover.


Thanks, jjp

Back in oh, I dunno... the late 70s I had a pair of HPMs as well. Maybe the 40s? I don't remember. What I DO remember is that I thought nothing was coming out of that driver either! If you feel like tinkering, oper her up and see if any wires are attached...lol.

I can recall the Pioneers being buy one, get the other for $1. IIRC, they were about $89 or so.

I also had a pair of the Rat Shack supertweeters, the circular ones. I think I perched them atop the Layfayette Criterions I had. As if they needed more treble energy... heehee. Oh, well... it was a good idea at the time.

cjpremierfour
05-02-2008, 07:46 PM
The HPM ribbon uses a crossover point of 12,000 hz. Very little information is carried in that freq band, this might be one of the reasons you are having trouble hearing this driver. Your age may also be a factor, your high frequency range will begin to decrease while getting older.
The HPM paper cone tweeter covers a range of 4k to 12k, if you add the realistic super tweeter using the main inputs, you will over lap these frequencies. You may want to check the input pots ( level control ) that go to the ribbon. I had a couple of dead spots in my pair that I worked out by turning it for @ 1 minute.
Good Luck!

al-dawg
07-15-2008, 10:23 PM
Hi,
I have a pair of HPM-100 that i purchased new in the 1980-82 time frame. I also have never heard anything comming from the ribbon tweeters. I took them to a repair shop long ago and the tech indicated that one ribbon was bad. I am not a technician, but I don't get any ohms reading when I tested them with my multi meter. In contrast, the paper cone tweeter in the HPM reads about 5.4 ohms and they are working fine.

The healthy and young human ear can hear up to 20,000 hertz. I am older but I know I can hear around 16k by using my EQ to filter out freqs below 16k. . I believe both my ribbons are bad and have open circuits.

Does this sound reasonable?

hermanv
07-20-2008, 09:05 PM
Tweeters are easy to blow up, ribbons are easiest of all. Normally ribbon tweeters use a step down transformer as most of them will be about 1 Ohm or less.

If the crossover capacitor is built into the tweeter an Ohmmeter won't work.