Koss CM /1030 model speakers. Any opinions on them?

Dabutcher

Pick them up today. Weigh about 75 pounds and are 39" high. Sound great to me. Never heard of them? Grew up with the Koss pro 4 headphones that sounded great. Wish I knew how to pop out the woofer dust cap on one of them? Tried my duct tape method to no avail? Thanks. D

cnh

Look interesting. I had no idea Koss ever made speakers that "big". The only Koss I've ever seen are the bookies below (M80s).

cnh

zane77

How about a vacuum to try to pull the dust cap, be gentle some have a lot of suction.

bigaltx24

They look well built, which is always a good sign.

Mystery

Koss did make some nice large speakers such as Model 160 that one of my fellow audio buddies (who has probably 200+ pairs of speakers) says is one of the best rock n roll speakers; as loud as CV but much much better sounding when loud.
If these are similar, you don't need another rock/party speakers.

jon s

I had a pair... The big weakness is the crossover switches. It's a three way toggle that was very fragile and broke all the time. Bass was pretty sold and the sound was pretty natural. The sonic weakness was it had average soundstaging and imaging.

[Deleted User]

If anyone ever sees a pair of Koss 1A available, let me know, please.

sgtmick63

I bought a pair of CM 1030's back in 1977. Kept them until 2002. Jon s is right, the crossover switches were terrible. They constantly broke. I loved the sound. I had them connected to a Yamaha CR- 1020 receiver then a Yamaha A-1000 int amp. In 2002 they really started to fall apart and I could not get parts. I went with polk rti 800, 1000, 2000, lsi9 then lsiM703. In short I wished that I had kept them and fixed them, oh well

Dabutcher

Thanks for all the info. . .i plan to try to sell them on CL for $125. . Been offered $80. If no takers @ my price. I want to pull all the drivers nd strIp varnish and restore them.

sgtmick63

FYI, the wood veneer is real Pecan

Dabutcher

Vacuum worked on larger woofer. Any hints on cleaning up the driver surrounds? The stickiness attracted lots of dirt and dust. My idea was soap and water w a toothbrush. Crossover network is crazy large for 1979? Thanks. D

Nightfall

What a rats nest, that's crazy!

Jeff Mackwood

Dabutcher (and anyone else reading this thread),

If you Google my name and Koss CM you should find plenty of references to me / posts that I've made about the Koss CM line of speakers.

Contact me at junk666email@hotmail.com and I can provide you with a Koss-original wiring diagram if you are looking to tackle (or have tackled) a crossover refurb - as well as other information and assistance. (The going rate for a pro refurb is ~$800 per pair. By now every pair will need to be refurbished. All resistors. Some caps - 1/2 the time - but you might as well have them done at the same time even if the originals are still within tolerance since the parts are cheap. It's the labour that adds up. I've had six pairs of CM/1030s done at SpeakerMart in Ottawa. I've had two other owners (one in Vancouver, one in the US) show me invoices for work they've had done and the parts and labour costs have all been essentially the same.)

From the pics posted you have the "old" version of the CM/1030. (Woofers and mids are flush mounted. Mids have their own wooden sub-enclosure within the cabinet. The "new" version has surface mounted woofers and mids, with plastic woofer rings, and a plastic sub-enclosure for the mids - among other differences.)

Glad the vacuum trick worked on the woofer's dustcap. Protect those drivers: there are no new original woofers and mids to be had. I do know of a source for new replacement tweeters (8 Ohms) and treble tweeters (4 Ohms): http://www.midwestspeakerrepair.com/. I've not seen or heard them myself, but other owners who I have been in contact with tell me they are an excellent match. They are certainly physically identical; with care you should be able to re-use the original plastic diffusers.

One other thing: I try to salvage parts from any "junkers" that I come across and provide them to anyone who needs them (free of charge.) Unfortunately, as of today I have given away all of my available spare parts - and I still have a very long list of people looking for specific parts. So if anyone reading this has a pair that they are just going to send to trash anyhow (typically because of multiple damaged drivers, badly damaged cabinets, etc.), there might be some components worth salvaging. Contact me if you'd like to donate them to the cause (I pay the shipping). For example there is a demand for the plastic faceplates and woofer rings - a fellow in Italy just let me know that the faceplate I put in the mail for him arrived yesterday safe and sound. Of course any salvageable (undamaged and working) drivers can be put to great use helping others get theirs back in shape.

Regards.

Jeff Mackwood

Dabutcher

Paid $24.99 for the pair and sold them on CL for $100.00. Thanks for the info. D

MAD

Never seen any Koss speakers that big.

I used to have a pair of koss m105 plus (powered speakers… powered version of the m80) that I used as the mid/high and a sansui 9090 running a pair of technics 15 as lows. I always thought the koss speakers sounded very natural.