Need advice: 3 way with active 10" subs? (maybe similar to NHT XdS)

**fjhuerta** · 23 February 2011, 13:49 Wednesday

Wow, Meniscus did it with X-Over Pro? Honestly, I'd never have expected that. IMHO, that's the worst software you could ever use to design a x-over. I'm not surprised you are disappointed with the sound of your speakers!

Don't go active in order to solve an inherent flaw in the crossover. I don't know if Meniscus designed it for you, or it was a stock unit they had, but I'm almost completely sure that's your problem, and you'll still have it regadless of whether you go active or passive. A 3-way is difficult, but not impossible for a first design. Maybe you can get someone to help you measure your speakers and design a good x-over? The drivers you picked are pretty awesome, in a passive design I'm sure they'll blow your mind.

**Bear** · 23 February 2011, 14:26 Wednesday

Originally posted by omegaslast

[..]but ive heard what a speaker should sound like and the midbass is severely screwed up on these.. a pretty big suck out. What i want is to abandon the concept of a 3 way design, and i want to abandon these cabinets (they were basically thrown in for free so dont fret... they have a lot of design flaws)[..]

any thoughts on what amp to get? or how viable this is? thanks

I'm not sure the tweeter would be my first choice, but the mid and the woofer are both solid, respectable choices. With a large-ish cabinet, the L26 can get down to 20Hz pretty easily, so this would be a great start to a true full-range musical speaker. As Javier indicates, this is probably a flawed crossover design, though the cabinet has a lot of problems, too (e.g., mid chamber is too big, spacing appears to be too big between mid and tweeter, etc.).

One thing of note vs. Javier's advice: an electronic crossover will allow you to play around with slopes and electronic filters a lot more easily than using a passive crossover if you decide you want to fix the three-way, rather than going with a two-way plus sub.

**---k---** · 23 February 2011, 14:56 Wednesday

Wow. Those a pretty. They should be able to make some nice sound. I'm not sure I see any reason to ditch the boxes. From the photos, they look very usable (well maybe the mid should be closer to that tweeter...)

Where are you located? If you can get those to/from Chicago, I know two guys that could make you a very nice crossover: CJD or Paul Carmondy. In other areas, there are others that can help. I'm not saying that you can't make a nice crossover, but I am saying that those are expensive drivers that are worthy of being massaged by a crossover guru.

For the sub amp, you could start with a simple PE 240W plate amp. That is the low end solution. After that, usually the recommendation is a Behringer crossover and whatever amp. Haven't been paying attention enough to comment on the Peavy.

**Undefinition** · 23 February 2011, 16:56 Wednesday

Why would you throw out the 3-way design? I think this would make a killer passive 3-way (with a good crossover, of course). Though a 2-way with a sub would be nice, too, no doubt.

The cabinets don't seem to have THAT many issues--aside from the distance from mid to tweeter. However, if you want to go with the PE cabinets, those are very nice, too.

If you plan on running the woofers sealed, you'll probably need a plate amp with some sort of EQ boost, which also means it will need a lot of wattage. (If the woofers were in the proper vented box, I think you could probably get them to sing full-blast with 100 watts or less.)

**omegaslast** · 23 February 2011, 19:34 Wednesday

Im just going to respond to everything in one post i guess

I got the tweeters for $75 a piece and wanted to hear some nice ribbons so i figured why not.

An electronic crossover would require a lot of amps right? I used to have a UPA-7 but now i have a xpa-3... so i cant really do that whole 3 way active thing. Plus i look at stuff like the minidsp and my eyes just glaze over.

I would prefer to stay 2 way + active subs, or just leave it with 3 way passive.

I was originally going to go with madisound and their leap software but AVS recommended meniscus audio to me (leap apparently just takes driver specs and spits something out, with no concern for cabinet design), thats why i went with them. I guess that was a mistake if this speaker pro software sucks that much. I gave them measurements of the cabinet and volumes, so i think this crossover was actually designed for me. The guy seemed knowledgeable enough over the phone and over emails.

I can leave them in these cabinets. The question is how to salvage them, does it require a complete crossover overhaul or what? Im going to have REW up and running and be able to provide measurements of the speakers soon...

**BOBinGA** · 23 February 2011, 21:42 Wednesday

Before you give up on the crossover that Meniscus designed, try a few things. First, it looks like a second order electrical XO from woofer to mid which usually works out to third order acoustic. Since you seem to think that there is a suck out in the upper bass, try running the mid electrically in phase with the woofer. That would be the prefered way to cross third order. Then if reversing the phase makes it sound too "tubby" try stuffing the woofer compartment pretty full if its sealed. The Meniscus XO doesn't look that bad, but it doesn't take the actual acoustic slopes into account and that could be the entire problem. Reversing the connections to the woofer is simple and might help a lot.

-Bob

**---k---** · 23 February 2011, 22:26 Wednesday

Read Paul's FAQ's.

Paul Carmody's DIY Speaker Pages - DIY Speaker FAQs

https://sites.google.com/site/undefinition/diy-speaker-faqs

Home > DIY Speaker FAQs

Then read this for a dairy of the process done right:

HTGuide Forum

https://www.htguide.com/forum/showthread.php?t=25031

**omegaslast** · 06 March 2011, 22:06 Sunday

So... I setup Room EQ Wizard and got this.
*look below*

Here's how I had it setup (hard to tell but its basically a foot away from the speaker inbetween tweeter and midrange)

I made a guess that near 200hz was where the speaker was falling apart, I wasn't far off apparently.

What can I do to solve the bass problem?

The bottom woofer is in a 1.5 cu ft vol so is that enough?

**Face** · 06 March 2011, 23:20 Sunday

Try measuring a little further back, on axis with the tweeter, and without any boundaries nearby. Do you have any bass traps or thick insulation laying around? If so, pile it up about 1' tall(or up to the woofer) between the mid and speaker, it'll help with floor bounce cancellation.

**Face** · 06 March 2011, 23:25 Sunday

FYI, 2.5ft^3 is optimum for a ported enclosure, so leave it sealed. A sub enclosure behind your mid will help it's low end.

**omegaslast** · 06 March 2011, 23:52 Sunday

Edit: Also did the mid woofer IN phase and it improved... woofer response (starting right at 350hz!) takes a big dump though

**omegaslast** · 06 March 2011, 23:53 Sunday

Originally posted by Face

Try measuring a little further back, on axis with the tweeter, and without any boundaries nearby. Do you have any bass traps or thick insulation laying around? If so, pile it up about 1' tall(or up to the woofer) between the mid and speaker, it'll help with floor bounce cancellation.

this is in the middle of a 14x19' room so theres definitely no boundaries. I have a ton of 1" sonic barrier foam i can stack up.

**omegaslast** · 07 March 2011, 00:00 Monday

Here it is with a bunch of 1" sonic barrier foam from parts express piled up to the woofer. also pointed directly at the tweeter and measuring a foot and a half away

**Face** · 07 March 2011, 18:27 Monday

Now invert the tweeter.

**omegaslast** · 07 March 2011, 19:11 Monday

Originally posted by Face

Now invert the tweeter.

Wow.. why did that get it so close to flat?! :E

Here's a comparison

If I stuffed polyfill into the woofer chamber would it increase the volume of the woofer or no? Right now all it has is some very light fiber glass from meniscus... from 350hz down its the only thing that goes out of the +/- 3db. I forgot to mention this but the woofer cabinet is only 1.5 cu ft... I'm guessing I want it to act larger than that?

**Undefinition** · 07 March 2011, 21:37 Monday

A few things...
First, for a large 3-way, I wouldn't recommend measuring from only a foot back. The time-of-flight from the woofer will be way off.

Second, are you using Pink Noise, Sine Waves, MLS to measure? If you're using MLS, then you aren't going to get much measurement below 200 Hz; it's the nature of the beast.

For a more accurate picture of the speaker's performance, I'd suggest placing the mic at your seated listening position and use Pink Noise.

**omegaslast** · 08 March 2011, 01:01 Tuesday

Originally posted by Undefinition

A few things...
First, for a large 3-way, I wouldn't recommend measuring from only a foot back. The time-of-flight from the woofer will be way off.

Second, are you using Pink Noise, Sine Waves, MLS to measure? If you're using MLS, then you aren't going to get much measurement below 200 Hz; it's the nature of the beast.

For a more accurate picture of the speaker's performance, I'd suggest placing the mic at your seated listening position and use Pink Noise.

i am using a 256k log sweep in REW (im guessing thats MLS)

so should i be putting the speaker where i would actually place it in L/R stereo? (thats about 14 feet away from me in a corner)

also how do i actually measure with pink noise?

**omegaslast** · 08 March 2011, 01:22 Tuesday

Originally posted by ---k---

Where are you located? If you can get those to/from Chicago, I know two guys that could make you a very nice crossover: CJD or Paul Carmondy. In other areas, there are others that can help. I'm not saying that you can't make a nice crossover, but I am saying that those are expensive drivers that are worthy of being massaged by a crossover guru.

forgot to answer this. i live in the bay area. about an hour away from Mr. Marsh in fact... is he a crossover guru? :T

Need advice: 3 way with active 10" subs? (maybe similar to NHT XdS)

Need advice: 3 way with active 10" subs? (maybe similar to NHT XdS)

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment