Millercarbon's Mega Moab Mod Meander


One of the all time great automotive engineers, Norbert Singer, was a key player in every one of the 16 Porsche LeMans victories from 1970 to 1998. His dominance was such that at one point Porsche had won LeMans more than all other marques combined. This was all accomplished by building on the already solid foundation of Porsche production models. The air cooled flat 12 in the 917 was really two flat sixes combined to make 12. This car so dominated motorsport the rules had to be changed to stop it!  

So Norbert Singer modified Porsche production technology to extract the absolute most for racing. His legacy is today’s Singer Vehicle Design https://singervehicledesign.com Norbert doesn’t make for a very good car name so they called it Singer. What is a Singer? It is a modified Porsche. It is in essence a hot rod. What Norbert Singer did was make the most hot rod racing Porsche. What Singer does is take that to the next level, capturing every aspect of Porsche right down to excellence of design and aesthetics.  

I am not anywhere near the level of Singer. But that is the spirit of what we are doing: taking an already world-class design and hot-rodding it to be even better. Well, better for me anyway- or so we hope!

The early modders started with substituting off the shelf parts to get more power or less weight. That is pretty much all we are doing here. Would be cool if some day people are doing this with a lot more sophisticated approach. Maybe they will. Maybe even I will. For now though we have the current crossover project.

My approach is pretty simple: better parts sound better.  

This lesson was learned back in the late 90’s with Linaeum Model 10 speakers. The designer had a new tweeter and told me how to modify the crossover for it. Simple mod, one cap, one resistor. Bought the parts from Radio Shack, put it together, sounded like crap. Absolute horrid crap! Called him up, he said those parts are crap. Said Musicap, Vishay. But they measure the same? Just do it. I did. It worked. Even though they measure exactly the same, the sound difference is off the charts.  

Even though they measure exactly the same. There is a lesson here. For those willing to learn.

So this is the essence of it: Eric Alexander has made a speaker the equivalent of a Porsche 911. Even better: an affordable Porsche 911! But after a while with my 911, after learning what makes it drive and feel the way it does, it was only natural to change the shocks and torsion bar and other items to bring out even more of what I like so much about the 911.  

That is what we are doing here. Hot-rodding a speaker. Thank you Rick for the metaphor!  

The parts are on order. Next week the fun begins!
128x128millercarbon

Showing 5 responses by nmmusicman

@millercarbon,

Excellent to hear about folks being curious about modding the crossovers in their speakers. I am good friends with a very prominent speaker designer whose had several very successful speaker companies and he has shared a few secrets with me about what makes a great crossover designs, some of which I can’t reveal for obvious reasons.

I have replaced the mid/tweet caps in one of my speakers from Mundorf EVO to Mundorf Silver/Gold oil and the results were not subtle at all! What was already a high resolution speaker became a liquid see through panorama with greater dynamic reserves and tonal density. This crossover is all point to point wiring with the leads of the components used to make the connections, inductors arranged in space and in relation to each other to mitigate interaction and shock mounted to minimize cabinet/woofer vibration infiltration. Each driver gets its own separate network arranged in space to minimize interaction again. 

One misconception I’ve heard and read about is that shunt component quality in a crossover don’t matter which is not true. Looking at the voltage signal it swings both positive and negative and this involves the shunt components as well. Being curious as I am, I replaced a shunt cap in a woofer circuit from a cheap elecrolytic 68uf 10v cap to a Mundorf EVO 68uf 450V cap and while the results were not as dramatic as those with the silver/gold oil caps in the mid/tweet circuits, it was certainly noticeable which surprisingly extended up into the mid and treble frequencies.

My next adventures are in high end resistors at some point.

Cheers


While I don't own a Porsche I do own an Audi TT but that's not the point. The guy that rebuilds the Powerdyne BD-11 supercharger for my S-10 ZR2 4.3l engine is a huge Porsche enthusiast. Check him out here:

https://928motorsports.com/


@millercarbon,

That's pretty much the same reactions I had when I finished with the Mundorf Silver/Gold Oil cap upgrades in my speakers. In fact, I called in sick to work that night just to sit and listen to this whole new world that was being presented in front of me. Best sick day ever!

They will get even better as you put time on them and the components break in so sit back and relax, you've earned it!
@millercarbon,

I got a big jump in resolution going from the stock spikes on the outboard crossovers to the Walker Audio Resonance control kit under each crossover. The solidity of each instrument in space is spooky and a real good recording just hangs in the air. Cymbal attacks are heavy and the weight of each cymbal can be clearly heard. Of course, average recordings are just as fun!

https://walkeraudio.com/product/valid-points-resonance-control-kit/
On my Alon Lotus SE mk ll speakers, I can swap between an AlNiCo magnet and a ceramic magnet on the dipole tweeter in a matter of minutes and the results are not subtle! The AlNiCo is much more refined with better definition and weight to instruments and overtones. The ceramic is still very good but lacks definition when compared to the AlNiCo. I would love to get the AlNiCo magnet woofers but sadly they are as rare as hens teeth and not many were made. One could choose between a 4 ohm woofer or 14 ohm woofer at time of purchase. I have both and the 14 ohm woofer is more defined and mates better with tube amps. The 4 ohm woofer mates up with SS amps and has great bass slam but lacks just a bit of definition IMO.

https://lh3.googleusercontent.com/proxy/xrrDtNBfJroe82wPM8YSNRzULz0vt8Wjm8TauGv2Yhbu3S7CzSdgauct3Exx...