[mlundy57]

With the Miflex caps, even the small values used for by-pass caps are huge in comparison to others. It’s the 600Vdc rating. IIRC, Sonicaps and Sonicap Platinums are 100Vdc. That extra capacity really bulks them up.

[Stimpy]

BTW, complex crossover. What loudspeakers are they?

My Acoustic Research AR-90's.  Four series caps and 4 parallel shunts.  I used a mix of Mundorf's, with EVO Oils for the main series values.  I added Mundorf Supremes or Supreme Silver/Oils, where I needed to build up values.  Some Auricaps in there too.  Parallel caps are Axon True Caps, with film and foil bypass caps.

[maty]

With the Miflex caps, even the small values used for by-pass caps are huge in comparison to others. It’s the 600Vdc rating. IIRC, Sonicaps and Sonicap Platinums are 100Vdc. That extra capacity really bulks them up.

[IMG, link] http://maty.galeon.com/WP-imagenes/kef-q100/KEF-Q100-crossover-MiFlex-bypass-2.jpg

[IMG, link] http://maty.galeon.com/WP-imagenes/kef-q100/KEF-Q100-crossover-MiFlex-bypass.jpg

[maty]

You are here too:

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9293-ar-9-ar-90-crossover-re-capping-adventure/

Older thread with big pictures.

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/4174-what-type-of-capacitors-should-i-put-in-my-ar-90s/&do=findComment&comment=72371

[IMG, link] http://www.classicspeakerpages.net/IP.Board/uploads/monthly_01_2008/post-101175-1200489092.jpg

Clean walls... No Rez or similar inside?

[Stimpy]

You are here too:

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/9293-ar-9-ar-90-crossover-re-capping-adventure/

Older thread with big pictures.

http://www.classicspeakerpages.net/IP.Board/index.php?/topic/4174-what-type-of-capacitors-should-i-put-in-my-ar-90s/&do=findComment&comment=72371

[IMG, link] http://www.classicspeakerpages.net/IP.Board/uploads/monthly_01_2008/post-101175-1200489092.jpg

Clean walls... No Rez or similar inside?

Yup, I get around...!   

I started my AR-90 refurb, some time back.  But, some health issues slowed me down.  Then, when I went to continue my refinish of the 90's, I found a pair of AR58S speakers, and after a recap, I've been enjoying them instead.  Though, this reminds me, that I really need to get back to the 90's.   

[maty]

The walls seem... aglomerate. Old speakers 

Before changing more components, such as resistors, it would be better to add a sandwich with viscoelastic material like No Rez, I think.

https://audiokarma.org/forums/index.php?threads/acoustic-research-ar90-recap-basic-xover-questions.711857/

[Crossover, IMG link] http://www.classicspeakerpages.net/IP.Board/uploads/monthly_01_2008/post-101175-1200137398.gif

[Stimpy]

The walls seem... aglomerate. Old speakers 

Before changing more components, such as resistors, it would be better to add a sandwich with viscoelastic material like No Rez, I think.

AR90's



Yes, I've already added extra bracing, and damping to the cabinet walls.  Also, added Dynamat to all the woofer baskets.  Mills resistors in place too.

[maty]

Now that nobody reads us, did you notice improvement by adding cushioning to the furniture? And with Mills resistors? You probably did it all at once.

Dynamat is very expensive!

Now, in you loudspeakers this vinyl rip would sound great. In glorious mono, LIVE.

Thelonious Monk Quartet - Mønk (2018), Vinyl, mono, Gearbox Records, US

https://www.discogs.com/Thelonious-Monk-M%C3%B8nk/release/12576350
https://www.diyaudio.com/forums/music/6958-playing-listening-post5999443.html

- End off topic -

[Stimpy]

Now that nobody reads us, did you notice improvement by adding cushioning to the furniture? And with Mills resistors? You probably did it all at once.

Dynamat is very expensive!

Now, in you loudspeakers this vinyl rip would sound great. In glorious mono, LIVE.

Thelonious Monk Quartet - Mønk (2018), Vinyl, mono, Gearbox Records, US

https://www.discogs.com/Thelonious-Monk-M%C3%B8nk/release/12576350
https://www.diyaudio.com/forums/music/6958-playing-listening-post5999443.html

- End off topic -

I haven't been able to do any serious before and after comparisons, due to the length of the restore.  But, I did do a recap A/B comparison, between a stock speaker, and the recapped high range drivers, of the other.  The post recap improvements were very pronounced.  Much cleaner and clearer.  No haze over the sound.  No opaqueness.  Very palpable.  Less noise too, as the old caps were sounding very distorted.

And thanks for the link.  Acoustic music always does well on a pair of AR's.  That'll make for a fun listening session.

[corndog71]

You are absolutely correct about the ClarityCaps.  Nice, but very colored, in some respects.  And that upper end roll-off, drove me crazy.  I was hoping it would improve with burn in, which it did to some degree.  But, I had to add bypass caps, to open them up a bit more, and the sound was still slightly muted in the highs.  While I like their sound, the Clarity's still aren't quite to my liking.  I might try a mix of ClarityCaps and Mundorf's, to see if I can get a better blend.

Clarity CMR are pricy but much better than the CSA/ESA series.  Otherwise I would recommend Sonicap gen 1 with copper or Teflon bypass. 

[Argoncat]

I started by-passing both tweeter and mid/woofer circuits. Everybody says I don't need it in the mid/woofer circuit but I like the result.

Mike

Are you still using bypass caps on both tweeter and mid/woofer circuits?  How does a bypass cap work on second order capacitor shunts in a low pass filters used for the mid/woofer; I thought bypass caps were used to reduce inductance at high frequencies..  TIA.

[VinceT]

I'm a total noob to DIY, this thread has been enlightening and a great read:thumb:

[dan2023]

I just got a pair of Koss M80 MTM speakers which I am thinking about recapping.  Since current caps are considered better than 40 years ago when these speakers were made, should I add a bypass cap?  And should I do both the tweeter and midrange?

[corndog71]

I just got a pair of Koss M80 MTM speakers which I am thinking about recapping.  Since current caps are considered better than 40 years ago when these speakers were made, should I add a bypass cap?  And should I do both the tweeter and midrange?

Maybe just take it one step at a time.  Start with tweeter caps.  Listen to the change and go from there. Bypass caps are not absolutely necessary.  Consider them seasoning.

[dan2023]

Thank you, I will go one step at a time.

[lokie]

Sorry to jump in here but...

What Bypass value do you all recommend for a 4 uF tweeter cap?

[mikeeastman]

I have by pass caps on both tweeter and mids.I  started with Sonicap platinum but switched to Milflex copper a nice upgrade.

lokie Danny usually uses .1uf for by pass caps.

[Argoncat]

The general recommendation is the bypass cap should be of higher quality and no more than ~1% of the target cap uF rating..