2. misc-audio
  3. 166577-121242

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
oldhvymec
5,101 posts
 
Solenoid Boxer (E) engine (motor). Cute!

https://www.youtube.com/watch?v=x4im3M9IFcI

Enjoy.. I did..

Few parts you could use in your new crossover.. :-)

I'll tell you one thing I noticed, the larger the cap and higher the voltage rating the longer it takes to brake in. BIG teflons take WAY to long. A guy at Parts Connection 15 years ago told me.. BE PATIENT.. He built the crossovers I was breaking in..

I though I was having a stroke a couple of times the wiggy sound that would come out those speakers 24/7 for 2 whole months. I borrowed a pair of NC400 class ds for the task... It worked.. Never again for me.

Copper foils and oils took 50 hours. Night and day in break in time. I just did a set on Six Pacs coupling (CF) and decoupling caps (AF)..

Happy Happy MC..

Regards
ricevs
1,543 posts
 
There is not much "info" out there on inductor direction.....pretty esoteric.  They measure the same either way and have no "outside foil" like a film cap so most people just do what they want.  As a long time serious tweaky listener, I wanted to find out if there was a difference.  A friend, who was building his own speakers told me his "crossover guru" said that the best sound was going into the inside.  At that time I had never played seriously with inductors.....but was building a three way that used the B&G Neo 10 planar and also the Neo 3 as tweeter.  I needed a xover around 3K.   I listened both ways to the coil in series with the Neo 10 and it was super clear that the "crossover guru" was correct.  I trust my ears.  The coil was a .59mh 12 gauge Wax foil coil from Jantzen.  Pretty easy for anyone to try this.  Listen for yourself.  Never trust anyone else. 

I consider inductors as the worse component in a xover.  Really great caps and resistors have very little sound.  A .59mh air core inductor has something like 70 or feet of wire/foil.  Do you think that 70 feet of OFC wire or foil wound on itself is not a serious veil?  I do.  My next speaker will not have inductors in series with the midrange or any driver.  I am making a stereo amp (one for each channel) for my friends planar panel system.  He is using 4 Neo 10s and 12 Neo 3s on an open baffle.  Currently he is listening to a coil and cap on the midrange.  What I am doing for him is to make a 12 db per octave filter at line level on the input stage of one channel of his modded Purifi amps.  By using seriously transparent parts at line level and running the Neo 10s directly from the amp he will have another level of transparency.  The Neo 3 tweeters can still be run with the cap/coil combo at speaker lever for very little loss....however, just now thinking it would be best to remove the coil to ground on the tweeter by just having a cap in series with the tweeter and do the second pole of filtering on the input of the tweeter amp.......thereby removing all coils from his speaker......yes, must do this.

By the way, a friend has the Lii-Audio Silver 10s (full range drivers) mounted on a 2 foot by 4 foot baffle with one by four wings going straight back.  97 db efficient, flat to 40 hz in his room.....has added ESS AMT on top with copper foil cap for slightly more air.  Bypassed the binding posts on the speaker so his speaker wire is soldered to the voice coil wire.  He is in heaven.  Total cost is around $2.5K......four drivers, wood and 2 copper foil caps.  Mind blowing sound.  He is going to add 2 15 inch custom open baffle woofs on each side to add some serious slam......running off Pass active xover with solid state class A amp for the woofs.  My next speaker will be something like this.
theaudiotweak
2,801 posts
 
My new crossover under much consideration will have no caps and will rely on 2 inductors and a resistor. Right now looking at Solen Litz wire inductors of 12 gauge or less. I can purchase 10 gauge and they can wind down to the values I need .2 mh on the woofer and .4mh on the ribbon tweeter. Not sure of the wire length but with these small values it should be short enough.
The Litz wire will have less skin effect than a comparable solid core or ribbon inductor and less  mutual capacitance and therefore more extended response..Only listening will tell for sure. Tom


ricevs
1,543 posts
 
I did not like Solen Litz inductors when I tried them. OFC Mundorf Foil inductors were way, way more transparent and extended (both were 12 gauge). Even the type of coating on a litz wire will have a serious effect on the sound. The thicker the coating....the worse the sound. Double coating is really a no no.  If you like slow fat veiled sound then Solen's are great.  I can see some people will think they are smooth.......and if you have bad electronics then a nice match.
theaudiotweak
2,801 posts
 
I can understand how the coatings will alter the sound. I do have a couple large value 10 gauge Solo not Solen foils I can wind down to a loose wind which I prefer to a tight machine wind More air in between the layers and less skin affect I would believe.  Tom
More to discover