AKG K702 (K7xx series) elastic loop replacement experience & notes

[Timber]

So today I finally got around to fixing my AKG K702's and thought I would post some results here, particularly as many on this forum also use the K7xx series. I might also be able to fill-in some of the blanks.

I am a huge fan of the AKG K7xx series and recently purchased the K712 Pro to sit alongside my nearly 5-year old K702's. As many of you will know these AKG headphones utilise an 'elastic loop' for the self-adjusting headband. Which is great at first but like all elastic loses its stretchiness and wears out eventually. This started happening to my K702's a few years ago even though I look after all my headphones. And unfortunately made them uncomfortable to wear as they began to slide down my head.

My various temporary workarounds included a hair tie in an x-formation or using clipped cable ties to stop the headband moving. However I wanted to see if I could do better, so I did some research and amongst the numerous threads found out the following.

1. The part number for the small elastic loop is AKG 2458A17010 (not to be confused with the inner headband assembly).
2. It can be ordered online in the US, but the company that sells it doesn't ship internationally.
3. I contacted Harman Support (from the AKG website) to see if anyone in the UK sells this part and as it is a AKG Professional Product they eventually referred me to a company called Sound Technology, who unfortunately haven't responded to my questions for the above part (this was before the Covid-19 shutdown). I haven't re-contacted Harman to see if they can still help with this query.

However in the meantime I bumped into this wonderful thread on Reddit where one fabulous person goes into immense detail on how to fit the above AKG elastic loop to their K7XX. Indeed this individual links to the complete AKG part breakdown if required. A big thank you to this person.

I would follow their guide but with some adjustments, below.

• I needed to improvise and use something in place of the official part and following some research found jewellery/haberdashery sellers sell thin elastic.
• I measured the K702/712 elastic and it is 1mm in width.
• I ordered 1mm elastic (£2.25 for 5m) which arrived today.
• Once the old elastic loop is cut from the headband (see the reddit link as to why) it measures just over 15cm in length. With the missing bit included I estimate that the AKG part is c.17-18cm in length.
• Unfortunately I had no obvious way to attach the two ends together so improvised by tying a very small triple knot and using sellotape to seal the ends (I know, not ideal). This adds 1.5/2cm to the length required to tie the knot.
• So I tried cutting various lengths off - from 19 to 22cm and testing the different loops in the K702.

Unfortunately I didn't take many pictures for every step of the way, although the fantastic Reddit guide already does that. Obviously it ruins the headband as you have to cut the elastic although the headband is arguably devalued with stretchy, old elastic anyway. But with the benefit that you can unhook the elastic when not in-use (as mentioned in the reddit thread).

Overall the fix has rejuvenated my K702s. The headband works again! So as mentioned I thought I would post here.

Some lessons learnt.

• Using the triple knot method, a length of 19cm for the replacement elastic works best atm. Although I sense you could go shorter for a tighter fit.
• Find a better way to connect the ends as per the official AKG part.
• You have to be careful with the left earcup as Mini XLR port means extra solder/wiring that could easily be broken off.
• Although I am reasonably confident the AKG elastic is 1mm, I'd be tempted to try 1.2mm (maybe 1.5mm) wide elastic next time as this new 1mm elastic feels ever so, ever slightly thinner than the elastic on my K712 Pro. I'm reasonably confident 2mm is too wide, particularly as the headphones have little guides for the elastic moulded into the plastic.

Anyway the whole things has made me appreciate the K702 again (after a few months adoring the K712 Pro) and I now fancy looking into new ear pads, maybe some headband padding and a shorter (ideally) garish colour XLR cable.

Can’nae take any more, Captain!...


The end result.

 

[Timber]

@delta0 thank you. I wanted to type up my notes in-case anyone else could find it useful, so glad if this post can be of use.

I used eBay to buy the elastic. I purchased from a seller called 'hotpinkhaberdasheryltd' - Round Hat Elastic Cord 1mm width (5mm in total) for £2.25, but it's pretty common so it should be fairly easy to obtain. High street craft shops are another option too. As mentioned my method can probably be improved upon - as per my thoughts above. It isn't a perfect replacement, although 18-months on and the replacement elastic is still holding on my K702's.

Although I've since had to solder a loose wire and the plastic on one of the ear cups has split so I don't think my pair will have many repairs left in them.

 

[Timber]

My issue is the clear plastic sliders on the insides has cracked completely. I can't see a way to replace them.

The only time I've seen that part is in an entire new headband (AKG 2458M98030 - although it include the elastic straps) but is sold by the same US-only company mentioned above. I think I did see it available in Europe once, but c.£95, and therefore completely uneconomical to even consider over a new pair. Unfortunately the big downside with AKG headphones it seems, particularly when compared to Beyerdynamics.

 

[Timber]

How about this mod then? He replaced the elastic with actual springs....

https://www.reddit.com/r/headphones/comments/p6fzpj/i_replaced_the_degrading_elastics_on_my_akg/

That's cool.

Shame the OP doesn't mention the parts although you can work them out. One danger per-say (aside from the comment with long hair) is that the springs have higher tension and therefore the headband applies more pressure (something that's just not an issue with elastic), but that's probably overthinking things.