Welcome! Need support, you got it. Or share your ideas and experiences.
Return to Planar Speaker Asylum
209.98.144.239
This is my first post. First of all, I'd like to thank everyone who gave how-tos and advice on MMG (and other) crossover mods in this group. Thanks to you, I was able to do an external crossover mod. I've never done anything like this before, and if you saw the inside of my external crossover box you'd probably laugh, but hey, it works, and it is a definite improvement. The most difficult part (other than getting the courage to do it) was that I used anticables for the internal wiring, and while I like it the wire is a little difficult to work with for something like this.Of course, now I'm thinking of ways to improve things a little, so I have a couple of questions. First off, these are the parts I used for each speaker: 24uf Sonicap for the high pass filter, a 25uf Dayton cap for the low pass filter, and a 2.2mH Erse SuperQ I-core for the inductor.
So these are my questions:
- I have read here that a bypass cap on the high pass filter can make an improvement, and that a Paper In Oil cap would work well. If so, what value should I use? Would 0.1uf be enough, or would .22uf be the minimum that I should use? Any suggestions on the brand?
- The bass definitely is deeper after the mod, but to me it seems a little muddy. Is it possible I need to reposition the speakers after the mod (certainly I can try this anyway)? Anyone have any other suggestions to possibly improve this?
Thanks in advance for any advice!
Follow Ups:
Can't advise you on bypass caps, but congrats on your project so far!
I recently tried some .1uf Mundorf silver in oils as bypass or add ons to my MMG external xovers, they added air to the treble and brings out more detail in the mids.I was in the process of doing some cap roll in my preamp in another system. So I was tring to put some burn in time on them.
After I did the swap, I tried the Audio Note copper in oil .1uf that came out the preamp, in the MMGs.
They were much smoother with less tizzyness in the top end.
So stay away from the silve rin oils.Your bass might get better as things burn in more, if not double check you polarity. That can be very tricky, as carefull as you may think you were.
You have done good so far, this is just the beginning.
Another member used a paper-in-oil shunt cap (from Allied) on his MMG's and he reported that the bass quality improved.If you don't want to try the Allied paper-in-oil cap, they're kinda big, try a pair of better quality 12uF caps. Multiple smaller caps should out do a single large one.
Thanks for the suggestions.I think I was pretty careful about the polarity, and I'm pretty sure I got it right. However, to check it, which wires do I switch? The midbass +/- on one speaker, see if it is better, if not the other one? Same with the tweeter +/- ?
Reverse one mid/bass first, see how that sounds, then reverse the other mid/bass to match the first one. See how that sounds.
See, its not just the polarity betweem the mid/bass drivers that have to be right, polarity between the tweeters and the mid/bass driver has to be right too.When I did mine I was very carefull to keep everything as straight as it was. However I guess because I went from the new crossover design back to the older one, when I first powered them up everything sounded confused. So I had to make the polarity changes.
Glad to hear your mod went well.IME thick wires muck up the bass on Maggies. You could try some thinner wiring say 24g. I like the ANticables theory, just not the guage.
Try it before dismissing it out of hand and see if the bass doesn't quicken up.
You can experiment for $5 with magwire from Ratshack.
I did the capless mod, so I can't advize on the bypass cap.
Also, if you haven't already, you can try dampening the crossover with some reptisand. FOr a messless test, I bet you could just sit it on your external boxes. My crosses are completely covered with this stuff.
YOu could also try some rope caulk and since it is removeable, you could undo it if you don't dig it.
Funny thing is that about two days after I closed up the socks, I saw one of your previous posts about the thinner gauge magwire. I will probably try it some time, when I feel like lifting up the socks again.A follow-up question on the reptisand -- do you have the crossover parts on top of a layer of reptisand, or are they tied down? Do you fill with reptisand pretty much to the top?
2 for 3,The crossover components are resting on a styrofoam pad, and sand is poured around them to the top of the enclosure.
Scruffy had a picture of his that he posted and I think he had something like 10 pounds of sand in the enclosure.
Some say not to fill them all the way because the sand isn't a good dielectric. You may want to half submege them, but I only had good effects from this, and so have others.
Ironically, while Maggies can suck up copious amounts of current, they don't need big-big wire to do it.Also, make sure your speakers are being held as rigidly as possible. Just a little vibration or movement can have a noticeable effect on bass clarity.
Let's face it, the real distance in our crossovers lies in the inductors and capacitors. If a wire is very short, it doesn't need to be terribly thick because resistance is cumulative across distance. It's just a thought.
Hey Wazoo,I agree, and you really do have to be careful with distance on the thin stuff.
But when you think of it, there are hundreds of ft of thin wire that make up the maggies drivers themselves!
I don't see what the big deal is to use 8ft of 12g when hundreds and hundreds of ft in the crossover or drivers is very thin anyhow.
On the bass, IME thick cables usually muck up the bass and blur the precision that maggies have.
I know the text book are stacked against me, but if you try the thin stuff, you will hear increased resolution in the bass. It will be less bloated, and some people dig this, and some are so used to the bloat, that they miss it. For me, I like the accuracy but YMMV.
I'm using some Litz wires I purchased in Germany 25 years ago. I've had to re-terminate it - the original silver pig-tails didn't hold up too well, besides I'm not keen on having 20' speaker cables when 6' cables reach. As you can see, the strands are rather fine and the cumulative gauge is well short of 'Monster' proportions. All I have to say about terminating Litz wire is that it's a real joy!
Cool wire. After 25 years it hasn't oxidized?
That's one of the beauties of Litz wire's enamelized strands. You'll also notice that the positive and negative wires all share the same jacket. In fact, they are woven around each other. The enamel that makes all of this possible also makes them a bitch to terminate. One has to use a solder pot and dip and skim and dip and... I don't have a solder pot, but I can improvise!
| ||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: