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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
 
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
5,268 posts
 
Actually, @idahifi, that's my other bit of advice.

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


timlub
1,649 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... 


idahifi OP
100 posts
 
I don't think leaving the old electrolytic caps in place is the solution. First, the jantzens ( when Tara cables not used), sounds far superior than the old caps being used with the Tara cables. So if I was going to throw my hands up , I would keep the jantzens and hunt for cables that didn't give me issue's. I tried those belden 5000 cables and didn't have issues and it sounded pretty good. 

Also this hasn't been driving me crazy, I've learned a lot and have enjoyed the project. 

I'm going to buy that meter test those caps, make sure there all good, and try and buy  resistors that compensate for any disparity. 

And if that does nothing, and I'm ready to give up, then I'll try different cables till I get the sound like I know it's supposed to be. 
That's the plan, but for now I've gotta move, so I'll be on a little break for a week or two
erik_squires
5,268 posts
 
Hi Ida,

I'm not advocating you keep all the old caps. Just the one's in parallel with the drivers. Those "shunt" caps.

So long as you are having a good time and learning new things, have at it.

What you might also enjoy, if you get Room EQ Wizard, is measuring your system impedance with the caps. Also measure the individual driver impedance (in box)

Then you can use something like XSim to simulate most of it and play around with different cap ESR in simulation. This will really help you see what is going on.

Best,

E
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