[grodri02]

Hi,

Looking to get some advice on upgrading my caps on my speaker crossover. I opened the speaker to get access to the crossover and this is what I found:






Looking at the values of the caps, the bottom one is a 100uF, 100V. The ones at top are 15uF, 8uF, and 4.7uF all 100V. Now they seem to all be electrolytic caps, but was wondering if I can put some film caps like the sonicap gen I since I dont want to spend to much on these inexpensive speakers (3-way Axiom Audio Speakers M80ti)? The sonicaps have those values expect for the 100uF....how can I get around that? Bypass maybe? Theres a Mundorf MKP cap that has that value?
Will the change of resistors be a plus since Im already taking it off.

Any help is much appreciated.

Thank you!

[mjosef]

@ 100uF for a film cap you are looking at some considerable cash. Sonicaps isn't cheap, maybe try Solens...you can parallel caps of smaller value to get the 100uF.
Good luck

[rollo]

  you may consider changing out the sand resistors first. Mills  non inductive resistors work well. Consider changing out the inductors as well. Creek inductors are reccommended.
  Caps ? There are so many to choose from. Take a look at the cap shootout here or Tempo Electric and read about the character of the caps tested. This will give you an idea of what to try. Have fun trying.


charles

[jtwrace]

http://www.humblehomemadehifi.com/Cap.html

[Danny Richie]

I have measured and tested a pair of the M80Ti.

I'd first recommend that you trace out the parts to see what you have. The pair that I tested had no high pass filter on the mids so it not only played down to the lower ranges, but was in parallel with the woofer in the lower ranges as well. This caused the impedance to drop to 2.4 ohms in the bottom end. I think that later models added a high pass for the mids.

The response was really rough too. The whole top end was really hot, and the two tweeters (bad idea) cancelled each other out quite a bit as the vertical measuring (or listening) location changed.

You might consider starting over with the crossover design if you have the ability.

The Skiing Ninja sent them to me and was looking into offering a redesigned crossover for them, but decided it just wasn't worth it.

[poseidonsvoice]

I have measured and tested a pair of the M80Ti.

I'd first recommend that you trace out the parts to see what you have. The pair that I tested had no high pass filter on the mids so it not only played down to the lower ranges, but was in parallel with the woofer in the lower ranges as well. This caused the impedance to drop to 2.4 ohms in the bottom end. I think that later models added a high pass for the mids.

The response was really rough too. The whole top end was really hot, and the two tweeters (bad idea) cancelled each other out quite a bit as the vertical measuring (or listening) location changed.

You might consider starting over with the crossover design if you have the ability.

The Skiing Ninja sent them to me and was looking into offering a redesigned crossover for them, but decided it just wasn't worth it.

See here.

Anand.

[Danny Richie]

The pair that I measured didn't look near that good.

Looks like that pair had the high pass filter on the mids.

Also, the photo's that I took of the network looks different than those. It is still the cheapest parts you can imagine, but looks different.

I wish the National Research Council of Canada would show some vertical off axis measurements. I guess they think we only hear what come directly from the speaker and what reflects from the side walls. By far the biggest and always untreated wall is the ceiling. So consistency in that directions is as important as any.

My vertical off axis measures showed that just a 4" movement up from center on those speakers made a 15db swing in the response from 1 meter away.

[poseidonsvoice]

The pair that I measured didn't look near that good.

Looks like that pair had the high pass filter on the mids.

Also, the photo's that I took of the network looks different than those. It is still the cheapest parts you can imagine, but looks different.

I wish the National Research Council of Canada would show some vertical off axis measurements. I guess they think we only hear what come directly from the speaker and what reflects from the side walls. By far the biggest and always untreated wall is the ceiling. So consistency in that directions is as important as any.

My vertical off axis measures showed that just a 4" movement up from center on those speakers made a 15db swing in the response from 1 meter away.

That speaker was reviewed in 2001. In recent years, I've seen better measurement resolution from the NRC. They do vertical off axis response measurements however they average it all together instead of showing it individually (Chart 2-Listening window graph). At least they have a council that measures, unlike the U.S. 

Come to think of it, you want a great lab for measurements in the U.S.? Send it to Harman international. Then you'll see the truth!

Anand.

[grodri02]

Thanks for your comments.

Just looking to get the most out of these speakers. Im happy with these and they have really open up with my recently purchased tube amp. So I was just looking to get a bit more out of them with some cap upgrades (after all, I did read you hear a substantial difference when ou upgrade caps). I will like to keep with one company for the values that I read and that seems to be the sonicaps with the execption of the the 100uf which will be a Mundorf MKP cap. Also, I understand that I should read the components first but that requieres me to take out the caps first. I already saw that one of the resistors did not match what my multi-meter was reading...the 7w5r read 3 ohms on my meter.

If I upgrade to the sonicaps will it be worth it?

[Danny Richie]

If I upgrade to the sonicaps will it be worth it?

Honestly, I'd fix other problems first, and secondly, I don't know if the speakers are really worth top level caps. Your money might be better spent starting over.

Adding top level caps to that speaker is a bit like putting racing slicks on a Toyota Prius.

If you really want to keep the speakers then swap out the caps to some decent poly caps like the Erse Pulse X, or Solen caps. Changing the inductors out to air cores and getting rid of the sand caste resistors won't hurt either, but then you are really starting to put a lot into it.

Then add a decent amount of dampening material to the inside as it was very difficult in that regards. That will help.

Lining the walls with some vinyl floor tiles is a cheap help too since the cabinet walls are very thin and not well braced.

And if you added about a .33uF cap in line with that top tweeter then it will eliminate the cancellation between them. It will change the crossover function doing that, but the response was pretty rough to begin with so it might not hurt it any more then the second tweeter does.

[grodri02]

Honestly, I'd fix other problems first, and secondly, I don't know if the speakers are really worth top level caps. Your money might be better spent starting over.

Adding top level caps to that speaker is a bit like putting racing slicks on a Toyota Prius.

If you really want to keep the speakers then swap out the caps to some decent poly caps like the Erse Pulse X, or Solen caps. Changing the inductors out to air cores and getting rid of the sand caste resistors won't hurt either, but then you are really starting to put a lot into it.

Then add a decent amount of dampening material to the inside as it was very difficult in that regards. That will help.

Lining the walls with some vinyl floor tiles is a cheap help too since the cabinet walls are very thin and not well braced.

And if you added about a .33uF cap in line with that top tweeter then it will eliminate the cancellation between them. It will change the crossover function doing that, but the response was pretty rough to begin with so it might not hurt it any more then the second tweeter does.

You have a good point. Lately, I been considering upgrading these speakers to a Quad 22L2. Heard they are really good and came recommended from a person that sell high end stuff! I'll try my luck to see if I can sell the Axiom at craigslist locally.

[sts9fan]

Rememeber, if you are enjoying them do not listen to the poo poo'ers on the interwebs.  You do not have to run out and buy new speakers just because some "experts" say yours suck.
 

[Danny Richie]

The "Expert" could have sold him the Sonicaps that he was interested in, but chose the way of honesty.

[grodri02]

Question: for the Solen or the ERSE caps, they dont carry a 8uF cap that my speaker calls for. They have the 8.2uF cap...will that be a problem if I install this 8.2uF instead of the 8uF?

Thanks

[Danny Richie]

Question: for the Solen or the ERSE caps, they dont carry a 8uF cap that my speaker calls for. They have the 8.2uF cap...will that be a problem if I install this 8.2uF instead of the 8uF?

Thanks

A small variation like that is not going to make much difference, but keep in mind the cap variance.

The Solen's are rated at 5% tolerance so an 8.2uF can be anywhere between 7.79uF and 8.61uF

The Erse Pulse X is rated to 3% tolerance. So an 8.2 can be anywhere between 7.95uF and 8.45uF.

Upon request I can measure them to match pairs on the low side or high side upon request.