Monitor Audio S6 tweek

[Rob_S]

Will be intrested to see where these tweeks go, may need to get out the parts box again :-)

[jerome69]

Originally Posted by PALUSE

Hi Everybody!Thanks for the support!

Dear Mr. Allen, you're right. If the S6 are similiar to the RS6, then the 22 Ohms resistor in parallel with the tweeter will drop the impedance around 0,7Ohms at 3Khz. Not a stress situation indeed!

Dear Mr. Jerome, you show some insight around the MA S6 X_over.
Did you listen some S6 with the mod you propose, or its an academic exercise, which contains a possible solution?
The Bass unit roll off is not enough, or the 10uF cap helps the integration of the bass unit with midrange unit?
Its well worth to try, only the 10uF in MKP caps are extra expensive. Maybe bipolar cans can do a decent job!Only the tweeter 10uF is crucial, and must be MKP type!

Hi,

It is not academic. I never heard a S6. But I have done enough tweaks to other loudspeakers to recognize the same topology of crossover and curiously the value are the same. These tweaks was done with actual measurements.
Tweak Eltax concept 400
Tweak JBL TLX215

The impedance compensation on the woofer helps to do a better roll off in the treble. Less bad treble in this area.

The treble should be more clear.
Let us know how it sounds

Cheers.

[AllenB]

Paluse, you can test with a cheap bi-polar to see if it makes the difference that you want. Mind that this tweak will cause phase differences that may produce a hole in the response, but it's worth a try to get the sound you want.

If you were to instead start with Robs parallel resistor and then add more and more series resistance, this will give a more predictable result.

[jerome69]

AllenB, the phase might be better I never see a tweeter, 1" dome, achieve an acoustical LR4@3kHz with a 12dB electrical. Second "Kiss-cool effect", the add-on capacitor pushes the tweeter resonance if near 1kHz, 10dB down ! Believe me you must heard the difference.

Good idea to apply each tweak step by step

[AllenB]

Jerome, your idea is worth a try. Of course how can any one of us be certain about our ideas from where we sit? (except Rob, of course who owns a pair). We are making educated guesses, but I'd dare to give Monitor Audio just a pinch of credit (or benefit of the doubt) vis-a-vis the phase, at least within a margin.

Sometimes tweeters will sound better when you take the pressure off the resonance, especially at higher power levels, but this is not really the effect that Paluse is chasing. Maybe I am not understanding your point when I assume it may only confuse matters to add the capacitor.

[PALUSE]

Gentlemen, thank you very much for your assistance!
I have two "projects" in hand at the time, so, after these two issues i start with the S6!
I'll kepp in touch!
Thank you so much!


Best regards

Paulo

[jerome69]

You welcome Paulo

AllenB, we are on the same channel . I don't have a S6 in my workshop.
I have understood two issues : too bright and this "lack of ambience retrieval"
The first I thing reduce the tweeter level. The second, this is why i just suggest this small tweak

[PALUSE]

Gentelmen, after all this time i decide to start tweak my S6. First of all, a simple 10uF cap in series with the tweeter. I never saw a tweeter in phase with the other drives. The aditional 90º delay in phase may help to avoid the "gap zone" in the tweeters response...or not.

I'll keep in touch.

Best regards

[system7]

Quite likely you'll be disappointed with the result. You're not describing what you find wrong very clearly, but I'd suspect it's harshness from metal drivers.

For the very top end, I'd suggest you try a Zobel network across the metal tweeter. This is typically 6.8 ohm 10W wirewound and a polypropylene 0.82uF or 1uF series network. It does more than you might expect because it makes a much nicer load for the amplifier without affecting impedance much.

Taming the metal woofer is trickier. You might try the same value Zobel across the 1mH bass inductor making what is called a tank. It's not a circuit I like much because it does some odd things reducing impedance to about 5 ohms at the high end, but it will sound radically different due to the 5kHz notch on the metal cone breakup region.

[PALUSE]

Today i start to unscrew the tweeter, but i dont get the unit out from its position. Do i have to put the box foward or there is other way to remove it avoiding damage the enclosure?

Kind regards