Update

The Ansar caps I used in the example in Yam_09  replicate the sound of the original silver cans exactly, if this is what you want then use the Ansar Supersound as indicated.

The stock NS-1000m have always had the reputation of being a bit Amp fussy and needing something rich sounding, with a highish damping factor, like a Luxman, to sound their best. When using my Nakamichi Power Amp (fairly neutral) with the stock speakers, I had to turn the mid range down by 2dB on the level controls and I have to do the same with the Ansar caps fitted. The metal dome mid range just has too much top end bias otherwise.

I have a lot of respect for the work done on HumbleHomeMadeHiFi in the cap tests and I nearly always agree with the results on the caps I have experience with. The comments they make about the Ansar Supersound is that they concentrate on the upper frequencies and are therefor not particularly neutral. I decided to try a more neutral cap, just for the location in series with the mid range driver (21uF) and see how that faired.

I settled on the fairly modest entry level Mundorf MCap MKP. The largest size (diameter) that will fit into the moulded pockets on the rear of the Yamaha x-over plate is the 4.7uF. So I used 4x 4.7uF and a single 2.2uF to make the 21uF needed. When I measured the individual caps for both x-overs, two were just over the nominal value and the rest were all just under. They were all closer than 1% which is a lot better than the stated 3% and something also picked up in the "Humble" tests. I added a 0.1uF to the bunch for one x-over and a 0.22uF to the other, this gave me totals of 20.996uF and 21.018uF which is more than close enough, note I didn't use a bypass with these. I left all the other caps as previous, including the bypass used on the Mundorf Supreme.

The caps fitted in nice and neat, a bit of silicone sealant was used to hold them in place and reduce vibrations. I ran them in for a couple of days before giving them a listen.

I can not over state how much of an improvement these caps make over either the stock Silver cans or the Ansar Supersounds. They work so much better with the mid range driver. The level controls can be set to normal, they are much more Amp friendly in this respect. The more neutral balance removes the top end focus and gives a slightly richer mid range with better (more realistic) piano in the lower part of the middle of the key board. This has been one of my pet hates on every pair of NS-1000m that I have heard, these caps cure it. They make for a very easy listen, without being over lush, sound stage has improved further and sibilance has all but disappeared (unless on the recording).

I was originally putting my NS-1000m back to stock spec to sell on, that decision may have now changed, as I am enjoying listening to them like never before.

This final combination is a winner, I can definitely recommend it. There are better caps out there, but in this application these relatively cheap caps just work. If you can use a soldering Iron, this simple capacitor replacement is actually an upgrade and will give your speakers a new, more neutral and natural sound. If you have a really bright sounding Amp using a percentage of ClarityCap ESA in this mid range bunch will help, but if your system is neutral stick to the Mundorf MKP.

That's as much tweaking as I will be doing on the Stock NS-1000M. If you want a quick and simple upgrade, recap as indicated, fit some better binding posts and hook up wire from the posts to the crossover and that's all I would do.

Yam_11 details the parts I used in the re-cap and also has measurements I took from the caps taken out, plus measurements from the stock inductors. These may be of use to anyone looking to attempt any x-over work.

Mods to the Stock Yamaha NS-1000m were completed in 2015

I then went on to make more radical changes in my NS-1000m Upgraded Project.

These changes included a new cabinet, semi active crossover and different bass driver.