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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
imhififan's avatar
imhififan
2,109 posts
 
Tim, my guess is a combination of difference of ESR and those old electrolytic caps dried out and out of specs, so a tester that can check the value of the caps and ESR will give us the answer.
One thing that surprised me was the cables made such a big different ...
timlub
2,039 posts
 
@imhififan  ... well, again,  ESR should've had the opposite effect.  The old caps matter, plus his Tara Labs are solid core.  Typically solid core are not as extended on top,  plus those Tara labs have some sort of circuit in them... But overall, you are correct, the Tara Labs should not have made such a big difference, unless there were other problems involved. Solder joint or one of the big caps out of phase or a combination is my best guess.
erik_squires
15,667 posts
 
Idahifi's experience is exactly what I've been talking about. :)

In a 2nd order hp filter, this problem occurs from a combination of:

- Very low DCR in the coil
- Very low ESR in the caps
- Too small a resistor in series with the cap
- The impedance of the next stage higher in Hz.

In the right combination of things, you end up with far too low an impedance in the next stage.

Of course, having a monstrous amp fixes this issue, but you'd be surprised how just a little dip around 3 Ohms or less can do this.

Inexperienced modders get themselves into trouble by trying to get the lowest possible coil DCR and cap ESR without understanding the entire circuit, and bam.

Best for them to only replace series caps. There may be some level shifting but it is more benign.

Best,

E
erik_squires
15,667 posts
 
Actually, @idahifi, that's my other bit of advice.

Restore the original shunt caps and leave it alone. :)


timlub
2,039 posts
 
@erik_squires  
Sean,  to make this easy, without driving you crazy,  I believe Eriks last advice is the most sound,  replace the caps except the 2 2200 mic caps,  I suspect that you'll be fine... 


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