NEO3 and NEO8 as dipole or in chamber?

[henriksommer]

Hi all,

I'm considering a 3-way speaker using the NEO3 and NEO8 with a Peerless HDS driver. Should I go for a dipole design or a monopole design with a chamber for each of the NEO’s? Does anyone have any experience with this? Please advice

[ashok]

I have the Neo 8PDR and I like the dipole sound over the enclosed driver. One thing that I noticed was that due to reflections from the rear of the tweeter , which can be quite random in intesity and frequency , it imparts a sense of greater depth to the sound. In boxed mode this is lost.
This effect is quite dependant on location but I am sure the effect will always be there.

The result is that I use it as a dipole . It sounds great.

The Neo 3 I don't have. If it is like the Dayton PT2 that I have , the rear is sealed and cannot be used as a dipole.

Let us know how your experiments go. My Neo8PDR is being used as a two way with a 10 inch bass driver crossed over around 600Hz. I still haven't heard the Neo 8 spit at me due to its sharp peak above 10Khz. I will be trying out the notch filter later.
I also want to test this system with a gainclone I am making.
Cheers,
Ashok.

[henriksommer]

Hi Ashok,

Thanks for your reply I suppose that your conclusion is: No NEO3 is needed. I actually wanted to use them to avoid that ugly peak above 10 kHz on the NOE8, and I wanted to avoid using a notch filter. But you are not using either. Has anyone else tried the NEO8 without the notch filter? Is it possible for you to show me some detailed pictures of how you mounted the NEO8? What fitler-type are you using?

[ashok]

Hi Henrik,
I will post pictures soon. My current set up is very skimpy as it was on test only. Tests usually last longer than intended because after set up there is no more time to redo it and make it look better!
The bass unit ( you never asked about ) is a Peerless CSX 850146 from Peerless. Wonderfully controlled sound. I cannot hear any cone breakup or nasties when driven directly from the amp. Even my 12 inch Peerless 831857 is quite good in that respect. I used that earlier but the 10 incher is better. These drivers need to work up to 600Hz properly. Beyond that they need to roll off well and not break up like the XLS series.

I need to compare the two bass drivers side by side . So some more testing to be done. So maybe I can put up some pic's later this week.
Basically the tweeters have wings on either side ( about 12x9 inch totally with the tweeter in the middle). It sits on top of the bass box with the bass driver fairly close to the top edge.
Note that I did not 'say' that the Neo3 is not required at all. In my setup the treble seems to be quite good and I don't miss much. But I have heard sharper treble from other systems and those who want that might use the Neo3 also.
On the forum I found both opinions. Some using it without additional tweeters and some who insist that tweeters are required. You could always buy the Neo3 later if needed. Ensure that the rest of the system is really good. Many systems kill 'fine' treble. You might end up blaming the speaker ! Don't forget the cables also.
I use a tubed TDA1541 dac and a Tubed hybrid power amp.
Speaker cables are very short ( about 9 feet ) and are heavy guage stranded copper wire .
Cheers,
Ashok.

[henriksommer]

Hi Ashok,

I look forward to see the pictures of your setup. I have no experience with ribbon drivers what so ever, so I'm trying to read as much about the subject as possible. This forum is great, because it seems that all participants are very knowledgeable, experienced and helpful.

I’m curious about your 10” CSX drivers. I have a sub-woofer with a 12” XLS driver in a system with the 12” passive radiator. I’m very satisfied with that solution. With the sub I don’t need a bass driver that goes deep, but I’m after a driver that can match the NEOs in clarity. Does the CSX deliver that? I have searched for discussions about the difference between the HDS and the CSX, but so far the answer is non-conclusive. It seems that the difference is, that the HDS has a cast frame and maybe some improvements to the motor. But are the differences audible?? Any comments

Thanx,
Henrik

[Thunau]

Originally posted by henriksommer
Hi all,

I'm considering a 3-way speaker using the NEO3 and NEO8 with a Peerless HDS driver. Should I go for a dipole design or a monopole design with a chamber for each of the NEO’s? Does anyone have any experience with this? Please advice

Hi,
I started with the Neo8 as a dipole midrange mated to a monopole bass (Dynaudio 24W100) and Vifa XT25 tweeter, but found that it made the system sound a bit unbalanced regardless of flat on-axis frequency response. I attenuated the back wave with a 2" thick panel of 703 pressed fiberglass wrapped in acousticly transparent fabric. That has given my speaker the right touch of spaciousness in the midrange. I guess the mechanical attenuation is about 3-6 dB depending on frequency. I use the Neo 8 with acoustic 3rd order Bessel LP and HP filters at 600Hz and 5000Hz. The crossover is active, but the notch filter for the 12k spike is passive. I ended up with a parallel noth filter with following values: 12Ohm//4.7uF//0.036mH. The inductor is actually two parallel 18AWG 0.7mH inductors that I got on sale from Madisound. The midrange is smooth and transparent. The XT25 used from 5000Hz up has a similar quality. No traces of any sibilance.
It will be a while before I build a speaker to replace these.
I will probably develop a passive version though, with a midbass that is actually available for purchase and use them for rear speakers to play back multichannel SACDs.

[Kensai]

I've just dropped a pair of Neo3 PDR w/back cup drivers into an old trusty set of Yamaha NS-6390s. Just disconnected the tweeter line (though left the tweeter in to keep the cabinet sealed) and ran the mid line (a 4" element which let me drop the Neo3 in without modification) which has a 2.5khz highpass on it to the Neo3, and it has very ably replaced both mid and tweet in those boxes. They sound outstanding now, especially given that the speakers can be gotten for $50 these days and $80 got me the pair of Neo3s and their appropriate round surface mount faceplates shipped.

Now all I need is a good replacement for the stock Yammy 8" driver. Need something that rolls off naturally around 2.5khz or so (I see loads of options in the 3khz-4khz range, and I'm guessing most of those would be appropriate) since they're running the woofer line full range with no cross over components inline (ah, CE grade spekers, eh?). Something with good transient response to mate with the high detail of the Neo3s, and possibly something that might give me a bit of useable bass below the speced 45hz of the original. Any suggestions?

Kensai

[mwmkravchenko]

The neo three can be run dipole or monopole. The monopole version is about 3 db less efficient. There is some front back cancelation.

But they sound so good.

I talked to their rep and the neo ten is supposed to be out in samples in the fall. Can't wait to get my hands on a pair and see how they sing!

Mark