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HELP AFTER MY MODS, My tweeters are subdued and weak-

So I have a pair of Mirage M1 speakers, I changed the caps in the crossovers to Jantzen Superior Z (for the tweeters) and standard z for the mids and bass.
 
I also changed the internal cabling to Supra Classic 2.5.

First Impressions-  Not burned in yet
The highs are there but really recessed in the background. Theres a song I reference and it has a steel guitar solo, I can bearly hear it through the vocals because its seems recessed so far back.

SO HERES THE QUESTION- Is that a symptom of unburned in cables and or caps, or is that just what Supra cables give you?

When I changed the internal cabling a few years back on the same model speaker, I used DH LABS t14 Silver plated cable, This had the opposite effect, it was super bright and fast, but it smoothed out and the brightness relaxed, leaving a lot of detail but not so much your ears bled.

But here its the opposite, its dull on the top end and the vocals kind of take over and blur out the top end.

idahifi
erik_squires
5,268 posts
 
So looking at the schematic, the two caps I would be most suspect of are C3 and C4. Note they have a resistor in series with them, so the overall resistance there must be important. I would suggest you go back to the original caps there, and listen again.

If this fixes your problem, you’ll want to figure out the ESR of each one by substituting larger R3/R4 to make up the differences.

Almost missed it, C1 is the same way. My suspicion is that the resistors in series are going to be really small , like 2-5 Ohms max. 

Best,

E
timlub
1,649 posts
 
C1 is in the woofer circuit
C3 & C4 are in the midrange
R3 is in the midrange
R4 is comp on the tweeter
I'd put a signal on these and let them burn in for 100 hours or so,  then listen again.  If these are anything, but a nice improvement in smoothness and detail from before the mod,  then there is a problem.  I'd let this play for awhile, then sit down for a serious listen. 

timlub
1,649 posts
 
Sean,  if you want to keep up with the speaker building hobby,  I would suggest something like this:
https://www.amazon.com/Hiyadeal-Inductance-Capacitance-Resistance-Meter/dp/B008QKJOCQ/ref=sr_1_23?ie...
This is really cheap, but I suspect it will give you fairly close measurements.  
erik_squires
5,268 posts
 
Hi Tim,

Yes, your analysis is correct. :)

Too low impedance in the second poles _may_ lead to lowering of system impedance above the cut off. I know it’s weird, but I’ve seen it and modelled it a few times. It is a real effect.

Whether that is what the OP is suffering from I am not sure, but the series resistors are a clue. Usually those are in place to prevent a dead short.  Fortunately, the proof of this hypothesis is cheap. :) Just replace the caps with their originals and listen. If that proves to be correct, then the OP knows what to fix.


Best,

E
terry9
931 posts
 
Now that I see your schematic, I suspect that you might want to experiment with different caps for C7, C8, and C9.

Since Jantzen are metalized poly, you might find a considerable improvement by going to MIT film & foil caps:  RTX series (styrene/tin) for values  3uF and below, or MIT PPFXS (polypropylene/tin) for values 3 < 12 uF. I use these for high end DIY, and I suspect that your M1's are worth it too.
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