New crossover for NX-Otica MTM

nickd · « **Reply #20 on:** 19 Jul 2020, 04:15 pm »

The Science is interesting, but the proof is hearing the increased resolution. An inexpensive way to make a really nice sonic improvement regardless of large cap brand or quality.

Mike, you probably already know those Miflex bypass caps are the real deal, but require more break-in than say a Sonicap. In my system they didn’t settle in for a couple of hundred hours. Worth the wait though. Can’t wait to hear your thoughts on the big copper caps too. I’ve been hearing great things about those.

Nice upgrade project,

mlundy57 · « **Reply #21 on:** 19 Jul 2020, 05:44 pm »

Quote from: nickd on 19 Jul 2020, 04:15 pm

The Science is interesting, but the proof is hearing the increased resolution. An inexpensive way to make a really nice sonic improvement regardless of large cap brand or quality.

Mike, you probably already know those Miflex bypass caps are the real deal, but require more break-in than say a Sonicap. In my system they didn’t settle in for a couple of hundred hours. Worth the wait though. Can’t wait to hear your thoughts on the big copper caps too. I’ve been hearing great things about those.

Nice upgrade project,

I've used the Miflex caps in a number of builds. I really like them. It's been my experience that while the Gen I and Gen II Sonicaps need about 100 hours, the Platinums needed closer to 400. My normal break in regime is play continuously for three days at varying volumes with a wide range of music, turn them off overnight, repeat for two weeks. That gets them a little over 300 hours. After that, it's normal listening.

Sonicjoy · « **Reply #22 on:** 19 Jul 2020, 09:54 pm »

I'm glad you are upgrading your crossover Mike! With all the new equipment you added recently you should take the speakers to their maximum performance. Can't wait to hear your thoughts on the upgrade.

mlundy57 · « **Reply #23 on:** 19 Jul 2020, 10:09 pm »

Quote from: Sonicjoy on 19 Jul 2020, 09:54 pm

I'm glad you are upgrading your crossover Mike! With all the new equipment you added recently you should take the speakers to their maximum performance. Can't wait to hear your thoughts on the upgrade.

My thoughts exactly. I’m going to go with the Path resistors if I can get them. The only other decision is wether to stick with the 16ga foil inductors I have or go with 12ga.

TexE4D · « **Reply #24 on:** 20 Jul 2020, 02:43 am »

Okay, I understand now what a by-pass capacitor does. I initially tried to look it up online but couldn't really find anything specific on the topic for crossovers.
The follow-up question, how is the value of the by-pass capacitor determined?

On my crossover upgrades in addition to the Copper Caps, I'm using the Duelund Cast Resistors and Munford 7awg copper foil paper inductors.

TexE4D · « **Reply #25 on:** 20 Jul 2020, 03:07 am »

Looking at your original crossover picture, is it detached from the speaker?
I'm looking forward to seeing the layout wiring buildout for your upgrades.

mlundy57 · « **Reply #26 on:** 20 Jul 2020, 03:10 am »

Quote from: TexE4D on 20 Jul 2020, 03:07 am

Looking at your original crossover picture, is it detached from the speaker?
I'm looking forward to seeing the layout wiring buildout for your upgrades.

Yes, they are external. The new ones will be as well

diyman · « **Reply #27 on:** 20 Jul 2020, 05:58 am »

Quote from: TexE4D on 20 Jul 2020, 02:43 am

Okay, I understand now what a by-pass capacitor does. I initially tried to look it up online but couldn't really find anything specific on the topic for crossovers.
The follow-up question, how is the value of the by-pass capacitor determined?

On my crossover upgrades in addition to the Copper Caps, I'm using the Duelund Cast Resistors and Munford 7awg copper foil paper inductors.

A capacitor’s ‘resistance’ to the flow of an ac current is called reactance rather than resistance, but is still measured in ohms. It is an inverse function of both capacitance and frequency. The formula for a capacitor’s reactance is X= 1/2πCf.

So if you want a low reactance in order to shunt noise or other high frequencies across a particular component you choose a bypass capacitor value based on the frequencies you are trying to shunt. The capacitor value can be fairly small if the frequencies are high enough. Since both the capacitance and frequency are in the denominator, increasing either one will reduce the reactance.

ccomplete · « **Reply #28 on:** 20 Jul 2020, 04:28 pm »

Quote from: mlundy57 on 18 Jul 2020, 12:52 am

I recall in the Super 7 thread some folks swapped the Mills resistors for Path resistors. Was there any upside to this?

I swapped out the mills resistor for a Path one on the tweeter in my Super Vs and the improvement was HUUUGE. Not subtle by any means. I would never consider using another Mills in a crossover after that. It was more substantial of an improvement than adding the miflex bypass caps I think and that was another huge improvement. So I imagine with the amazing tweeter of the nx series it would be even more noticeable.. can’t wait to get mine.

mlundy57 · « **Reply #29 on:** 20 Jul 2020, 04:59 pm »

Quote from: ccomplete on 20 Jul 2020, 04:28 pm

I swapped out the mills resistor for a Path one on the tweeter in my Super Vs and the improvement was HUUUGE. Not subtle by any means. I would never consider using another Mills in a crossover after that. It was more substantial of an improvement than adding the miflex bypass caps I think and that was another huge improvement. So I imagine with the amazing tweeter of the nx series it would be even more noticeable.. can’t wait to get mine.

Thanks

mlundy57 · « **Reply #30 on:** 20 Jul 2020, 07:39 pm »

The Path Audio resistors are ordered. Once they arrive I can start laying out the crossovers.

Hobbsmeerkat · « **Reply #31 on:** 20 Jul 2020, 07:52 pm »

Quote from: mlundy57 on 20 Jul 2020, 07:39 pm

The Path Audio resistors are ordered. Once they arrive I can start laying out the crossovers.

Man, you really got some goodies in store then! I'm even more excited to watch things progress!

mlundy57 · « **Reply #32 on:** 20 Jul 2020, 08:50 pm »

Quote from: Hobbsmeerkat on 20 Jul 2020, 07:52 pm

Man, you really got some goodies in store then! I'm even more excited to watch things progress!

Yep

I hope it ends up being worth it.

Endo2112 · « **Reply #33 on:** 20 Jul 2020, 11:06 pm »

I can confidently second the path audio resistors as well, looks like a fantastic set-up Mike.

Cheers,

Don

Captainhemo · « **Reply #34 on:** 21 Jul 2020, 07:22 pm »

Yup, that is well explained

And, just to be clear, if there is a felt pen rating onthe cap, it was measured by Danny, he typically measures and clsely matches caps. Whether he's doing this with the new coppers, I don't know and didn't notice on mine .

Mike, glad to see you take the plunge, you're going to be happy but give them time.
With regards to the Path Audio resistors, have not changed mine out in any speakers, always run the Mils. However, we did add a pth to the notch filer in Don's NX-Tremes... come to think of it, I think they were actually Duelands..... worth while ? I I can't say but if you've gone this far..... LOL

jay

Hobbsmeerkat · « **Reply #35 on:** 21 Jul 2020, 07:25 pm »

I can only imagine what this kind of upgrade would do to a setup like the super minis which are already incredibly fast & detailed..

ccomplete · « **Reply #36 on:** 22 Jul 2020, 05:04 pm »

Quote from: Captainhemo on 21 Jul 2020, 07:22 pm

With regards to the Path Audio resistors, have not changed mine out in any speakers, always run the Mils. However, we did add a pth to the notch filer in Don's NX-Tremes... come to think of it, I think they were actually Duelands..... worth while ? I I can't say but if you've gone this far..... LOL

I forget, are the Super 7 tweeters padded down with a resistor? If so you guys are really robbing yourselves not trying out this simple upgrade! After everything that goes into these speakers it’s really such a simple step. Even the Super V showed a drastic improvement in sound quality. I did the crossover upgrade in steps adding the path audio resistor first and the bypass caps a few weeks later. Equal improvements across the board 👍 looking forward to hearing back from Mike when it’s all done!

mlundy57 · « **Reply #37 on:** 22 Jul 2020, 05:29 pm »

The Path Audio resistors showed up today. Since my amps are fully balanced and the negative wire is not ground, I'm going to connect the ground legs of the resistors to a third binging post on the input side of the crossover. Then I can run a ground wire from that binding post to the chassis ground stud on the amp.

That was fast delivery. I ordered them Monday afternoon my time (central) and they arrived from England this morning.

ccomplete · « **Reply #38 on:** 22 Jul 2020, 05:43 pm »

Quote from: mlundy57 on 22 Jul 2020, 05:29 pm

The Path Audio resistors showed up today. Since my amps are fully balanced and the negative wire is not ground, I'm going to connect the ground legs of the resistors to a third binging post on the input side of the crossover. Then I can run a ground wire from that binding post to the chassis ground stud on the amp.

That was fast delivery. I ordered them Monday afternoon my time (central) and they arrived from England this morning.

I - and everyone I know who’s used them - just leave the 3rd ground wire to the casing unconnected. I’ve never tried it connected and don’t see it as necessary, there’s not a lot of noise going into the resistor at the speaker level where it would need to be shielded.. maybe try without going to the extra trouble first, but if you try both ways and one is noticeably better let me know!

Captainhemo · « **Reply #39 on:** 22 Jul 2020, 06:38 pm »

Quote from: ccomplete on 22 Jul 2020, 05:04 pm

I forget, are the Super 7 tweeters padded down with a resistor? If so you guys are really robbing yourselves not trying out this simple upgrade! After everything that goes into these speakers it’s really such a simple step. Even the Super V showed a drastic improvement in sound quality. I did the crossover upgrade in steps adding the path audio resistor first and the bypass caps a few weeks later. Equal improvements across the board 👍 looking forward to hearing back from Mike when it’s all done!

No, the tweeter is not padded in the S7 network

jay