InDIYana build - SuperNova Minimus

[wogg]

What happened to the part about the imm 6 ? i went to look for the downloads you were using and now it’s gone!

I made an edit and it said flagged for spam. Hopefully it comes back after the moderators look at it.

[Mountainman Bob]

I made an edit and it said flagged for spam. Hopefully it comes back after the moderators look at it.

It’s happened to me a few times too.....kindly more annoying than the spam! What’s that about having cake and eating it too?

so you think this imm 6 is good enough to actually use in speaker design? I’m using mine with ‘audio tool’ seems smarter than me....hopefully I can figure out how to use it!

[wogg]

I sent a message to [email protected] this morning, hopefully that post isn't gone forever. I put some time in documenting the process and didn't write it elsewhere.

[Mountainman Bob]

Yah, I”m losing stuff right and left due to editing......gonna have make sure I preview and edit from now on.

Don”t know why editing your own post would throw up a spam flag.....must be a glitch?

[[email protected]]

I sent a message to [email protected] this morning, hopefully that post isn't gone forever. I put some time in documenting the process and didn't write it elsewhere.

Replied privately, but I'll mention it again here:

I unfortunately have no power over deletion/flagged posts/etc. Even though I'm listed as a mod, the most I can do is infractions and the like.

I'll look into it, that's about the most I can do currently.

Scott

[Mountainman Bob]

Replied privately, but I'll mention it again here:

I unfortunately have no power over deletion/flagged posts/etc. Even though I'm listed as a mod, the most I can do is infractions and the like.

I'll look into it, that's about the most I can do currently.

Scott

Thanks Scott,

seems as as though if you edit once your golden, edit twice and your gone!

[wogg]

Still tweaking crossover. I decided to try a series crossover to see if I could do better. This is a second order series network, I got it flatter as a system by quite a bit. I do worry about that tweeter Fs though, it's obviously not filtered as well as the parallel setup and is only 15dB down.

Green is the parallel crossove posted above for reference.

The tweeter is very robust, but distortion is above 1%, up to 3% below 1kHz for second order. I dd this sweep before, and it had the accidental EQ at the top, but that didn't affect the important part.

Any prior experience on series crossovers to chime in on if that tweeter would be a problem like this?

[xmax]

It's hard to tell with the resolution of your Xsim graph the first line being at 1K, the RST might be able to handle
-15dB @ Fs, (at moderate volume) but I'm not so sure about the Vifa. That said the distortion curve does not
show any major rising THD with the lower end of the tweet output.

[wogg]

It's hard to tell with the resolution of your Xsim graph the first line being at 1K, the RST might be able to handle
-15dB @ Fs, (at moderate volume) but I'm not so sure about the Vifa. That said the distortion curve does not
show any major rising THD with the lower end of the tweet output.

The lower boundary is 300Hz, where my measurement data is gated. I'm leaning toward trying this, I'm really impressed with the distortion measurement on that tweeter. The 3rd and 4th harmonics remain under 1% until below 500Hz. I'm thinking the system in this arrangement will remain under 1% across the whole spectrum, with under 0.5% above 2kHz.

[dynamo]

Good looking build! I worry that rising top end is gonna bother you though

[badman]

Good looking build! I worry that rising top end is gonna bother you though

It definitely will long-term. I'd jig up a little switch-bypassed inductor to tame it- you can tune it to taste with a resistor as well, and switch it out if you feel like you need a little more "air" in your sound. Most prefer a downward sloping in-room response, so it's likely to be a long-term issue. Short term, you'll probably love the "clarity" and "space" that a treble boost brings, but with that comes fatigue and disinterest.

[wogg]

Actually that top end rise is a personal preference of mine. I'm at my component limit for InDIYana, so an extra inductor to compensate isn't in the cards immediately.

I haven't done any off axis measurement yet, but on the spec sheet that rise disappears. I'm thinking I'll toe them out a touch at the competition, and possibly add an inductor later. The likely owners of these down the road is an old ('er than me) dude that probably can't hear up there anyway

[wogg]

I want to buy parts but I can't decide which compromise to go with. I messed with the parallel version some more, focusing on a LR4 target for the tweeter at 2k with a BW2 target for the woofer at 1.5k. That increases the output below 4k a good 4dBish, which will come up to that top end rise, but leaves a 5dB drop from 4-6k with the rise back up all the way to 20k. The series version has less of a speedy dip, but has that top end rise.

Parallel is cheaper... series has an easy fix by adding 0.13uH to the tweeter and killing the top end rise later... decisions. Comparison sims...

Parallel


Series

[4thtry]

In the last XSim graph, what does the phase tracking look like for curves S1 and S2 (leaving the phase off for the Sys (blue) trace)? Not sure how important phase tracking is, but I always like to look at it to see how the individual driver phase angles meld together through the crossover region.

[wogg]

The series version tracks pretty smoothly. The reverse null isn't too deep and is pretty wide, but the phase curves look pretty close. It seemed to me while playing with it that a series crossover forces the phases in a way since they depend on each other... don't know the technicials behind that, but that's my guess.



The parallel version does have a much deeper and narrow reverse null, even though the tweeter phase is rotating much faster than the woofer (product of slope),