I have a schematic for the CM1030 speaker and can tell you where each wir of the crossovder goes
Maxdangr
Maxdangr
Need Help with Koss CM-1030 speakers
I am trying to put a pair of these speakers back together for a friend. A previous owner ( we'll call him "idiot" for short ) hacked out all kinds of wiring and removed factory installed switches, etc... As such, i'm trying to take these back to factory stock and go from there.
The crossover is PHENOMENALLY tough to follow and i've already had Jon Risch try to figure it out. After sending him one of the crossovers to examine, he's pretty confident that he was able to get it right but i would like to make sure. If someone has a pair of these and is willing to tell me where each wire goes ( they are all color coded ), i would be forever indebted.
For those of you that aren't familiar with these speakers, they are large floorstanders that were manufactured in 1979 and retailed for $1100 per pair. The cabinets are beautifully finished, very well built and clock in at 74 lbs apiece. They make use of a 10" vented woofer, two 4.5" cone mids, a dome tweeter and a dome super tweeter. The crossover is of a very complex and advanced design and this is where the problems begin.
Jon's thoughts are that this might have been the first commercial speaker manufactured with a series crossover with impedance compensation, notch filters and padded attenuators built in. He was amazed ( to say the least ) that any manufacturer had the "guts" to use such a highly advanced and parts heavy design in a production model, especially back then. He told me that it may be the most complex passive crossover that he's ever seen and was VERY hard to try and back-track. I fully agree with him and that is why i had asked for his help in trying to figure it out.
In case you are going to suggest that i contact Koss about this, they have absolutely NO records of ever making such a product. I am 100% certain that it is a Koss product though, as all of the labels are still on the speaker and i was able to research them in several different buyer's guides of that era.
I would not bother with such an old speaker, but the drivers and cabinet are all in MAGNIFICENT shape. My guess is that the contacts that work the padded attenuators failed and the "idiot" must have tried to bypass them via hard-wiring. The only problem is that the attenuators have multiple stages and they left most of the wiring just lying inside the cabinet and pulled the switches. As such, there is no way for me to see where anything originally went and that is how we ran into the aforementioned problem.
Is there ANYBODY out there that has a pair of these and can help me out ? Sean
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The crossover is PHENOMENALLY tough to follow and i've already had Jon Risch try to figure it out. After sending him one of the crossovers to examine, he's pretty confident that he was able to get it right but i would like to make sure. If someone has a pair of these and is willing to tell me where each wire goes ( they are all color coded ), i would be forever indebted.
For those of you that aren't familiar with these speakers, they are large floorstanders that were manufactured in 1979 and retailed for $1100 per pair. The cabinets are beautifully finished, very well built and clock in at 74 lbs apiece. They make use of a 10" vented woofer, two 4.5" cone mids, a dome tweeter and a dome super tweeter. The crossover is of a very complex and advanced design and this is where the problems begin.
Jon's thoughts are that this might have been the first commercial speaker manufactured with a series crossover with impedance compensation, notch filters and padded attenuators built in. He was amazed ( to say the least ) that any manufacturer had the "guts" to use such a highly advanced and parts heavy design in a production model, especially back then. He told me that it may be the most complex passive crossover that he's ever seen and was VERY hard to try and back-track. I fully agree with him and that is why i had asked for his help in trying to figure it out.
In case you are going to suggest that i contact Koss about this, they have absolutely NO records of ever making such a product. I am 100% certain that it is a Koss product though, as all of the labels are still on the speaker and i was able to research them in several different buyer's guides of that era.
I would not bother with such an old speaker, but the drivers and cabinet are all in MAGNIFICENT shape. My guess is that the contacts that work the padded attenuators failed and the "idiot" must have tried to bypass them via hard-wiring. The only problem is that the attenuators have multiple stages and they left most of the wiring just lying inside the cabinet and pulled the switches. As such, there is no way for me to see where anything originally went and that is how we ran into the aforementioned problem.
Is there ANYBODY out there that has a pair of these and can help me out ? Sean
>
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- 11 posts total
- 11 posts total