[KOSS4LIFE]

Hi, I have a pair of old(not Pro 4AAAT) Koss headphones that I would really appreciate help on finding a driver for. I am for sure that it is the driver and it is the right driver. If you guys could help, that would be awesome! So, if you guys could assist me in finding a driver I would be extremely happy as these are my only headphones (from my dad), and happen to be my favorite of all other ones I've tried.
 
Thanks in advance,
 
 
Hayden

 

[obobskivich]

If they're newer than the mid 1980s, Koss will repair them forever, just send them in with a note and $6 or $7 (I think it's $7 now) for the return shipping. If you're unsure if they're covered, just contact Koss and ask - it's amazing what they actually have parts for sometimes.

 

[KOSS4LIFE]

Thanks for the reply! Unfortunately, I have already emailed Koss, and was told that my product was no longer supported by the warranty(I saw quite a few threads about people doing that and their's being covered by the warranty). Then again, even if it was, mine has been opened and "modified" I guess you could say, because of when my dad removed the old driver and replaced the 1/4 plug. So, besides that, do you have any other ideas of where to get one? I'm completely out of ideas. :/

 

[obobskivich]

Thanks for the reply! Unfortunately, I have already emailed Koss, and was told that my product was no longer supported by the warranty(I saw quite a few threads about people doing that and their's being covered by the warranty). Then again, even if it was, mine has been opened and "modified" I guess you could say, because of when my dad removed the old driver and replaced the 1/4 plug. So, besides that, do you have any other ideas of where to get one? I'm completely out of ideas. :/

I've never known Koss to care about minor modifications, but if it exists outside of their Lifetime Warranty period, they likely don't have hardware for it.

Regarding a replacement driver - I honestly don't remember if the PRO4AA and PRO4AAA use the same drivers or not. If so, you could just buy and gut a 4AA (they're $100 new all day). The other idea would be to upgrade/replace them with something different - I'm sure they weigh an absolute ton (just like the 4AA and 4AAT), and while they probably sound good, they probably don't sound fantastic. Here's an example of something I'd consider as a replacement:
http://www.tuesdaymorning.com/tony-bennett-signature-edition-stereophones/1255982.jsp (I would, and did, take these over the PRO3 and PRO4AAT).

 

[KOSS4LIFE]

Hmmm. Too bad these things are so old and basically non-existent anymore... If I had the money, I would probably try buying a new Pro 4AA or AAAT, but I really don't have much money to spend. Too bad there isn't some sort of replacement driver I could buy. Since I've been checking eBay and craigslist an haven't found anything, do you think I'm basically out of luck? I' m really disapointed that I only have one side working and not enough for a new/used pair.

 

[obobskivich]

Hmmm. Too bad these things are so old and basically non-existent anymore... If I had the money, I would probably try buying a new Pro 4AA or AAAT, but I really don't have much money to spend. Too bad there isn't some sort of replacement driver I could buy. Since I've been checking eBay and craigslist an haven't found anything, do you think I'm basically out of luck? I' m really disapointed that I only have one side working and not enough for a new/used pair.

Pro4AAAs are sort of rare, you can probably find one if you hold out long enough (though they may end up costing close to $100), but honestly I'd use this as an opportunity to try something newer (and lighter). The TBSE are a great deal at $50, for example, and they do come with the Koss lifetime warranty.

 

[qazxsw80]

It's not difficult to buy a pair on ebay(There is one or two pairs every week). Get one and replace the driver .It's about 50$. AAAT has different dinamics and sounds much worse then old 4AAA.

 

[KOSS4LIFE]

I've heard that the 4AAAT isn't so great. Also, I've been looking on eBay for a while, but when they pop up, people always sell them as auctions and I can't seem to get my hands on a set!

 

[DkossZoSo]

All vintage 70-s fnd 80-s koss has same 50 mm 250-ohm lavsan drivers. Model 4aa is most popular, and costs not much. You can buy this model in working condition on ebay for 15 - 20 us dollars and took drivers from it for repairing other vintage Koss phones, especially pro 4aaa.
 
Best regards.

 

[KOSS4LIFE]

Thanks for the reply! So does that mean that the Pro4aa drivers are the same as the Pro4aaa drivers? I've seen lots of Pro4aas that I could have got, but I thought they had different drivers.

 

[DkossZoSo]

Exists 4 types of vintage Koss drivers. All of them has 2 inch dynamic elements with 1 inch 250 Ohm voice coils. Sound of them is nearly same.

1)    1970 – 1980 – white or black colored speaker with a plastic nut, which regulates the foam damper.
2)    1980 – 1988 – black colored driver with metal nut and frame. Dumper made of rubber.
3)    1988 – 1996 – black colored driver, with thinner membrane and magnet with thin plastic housing, without large metal nut. Damper made of paper.
4)    1996 – nowadays. Titanium series drivers – sound is quite different! Damper looks like series 3.
 
1 – 2 series has the same membrane, and same "vintage" sound. But, 3 - 4 series is not recommended for repairing your vintage phones, they sound not very well.
 
 
Series 2

 
Series 2

Series 1

Series 1

Series 1

Series 1

Series 2

Series 3

Series 2

Series 1

 

[KOSS4LIFE]

Wow, that is awesome! Now I can look for a pair to fix my Pro4aaas! I have the series 2 driver, but have never seen the series 4 driver. Thanks so much! Finally, I find out that they are the same!

 

[DkossZoSo]

Right one is Series-4 (Contemporary) 250 Ohm Koss driver. If you will send your phones to koss warranty, they put series-4 driver. It has deeper bass, but sound is not detailed and non-agressive.

 

 
Frequency response difference between them looks like this:

 
 
Also, beware of damaging driver, when replacing it. Taking it from its case, you must not move aluminium ring. This ring holding the diaphragm. If you be not careful, you damage driver such way

 
One man damaged driver on head fi. Very pity process of killing vintage drivers. BE CAREFUL!
http://www.head-fi.org/t/210679/vintage-koss-hv-2as-opened-up-pics-need-help-w-repairs
 

 
Best regards from Koss!

 

[KOSS4LIFE]

My driver just gave up on me for some reason, and it wasnt actually me who pulled the driver out, so when it got removed, the diaphragm got ripped off rendering the whole driver useless. It's really easy to break the drivers too. Oh, and Koss said that they cannot repair mine because they don't had headband parts, meaning I can't send it in and get a driver from them. That's why I started searching for a replacement driver last year when it happened, but with no luck yet.

 

[DkossZoSo]

Try this one!
http://www.ebay.com/itm/Vintage-Koss-PRO-4AA-Headphones-No-Reserve-/251176021312?pt=US_Headphones&hash=item3a7b41ed40