B&G NEO8 PLANAR TRANSDUCER crossed to two Dayton classic 8"(DC200-8)
Hello all,
First off I am new to this hobby so bear with me.
The plan, simply stated above is what I am thinking, enclosed in a transmission line of course. Now from what I have read 2-way systems are simpler, especially for a newbie but will cost about the same if you want deep bass extension, so that is the goal. However, $63 a piece for the planar, I might want to go 3-way. On the flip sied, from reading other posts, it seems desirable to avoid having a crossover in the critical region based on the Fl/Mun. curves, hence the B&G's that cover 500hz up to 20k and the dual 8's should only be a couple dB's down in the high 20's (hz) which is fine.
Now part of my question is does anyone have any experience with these B&G's (partsexpress 264-712)?
The other part and I dont know the technical term to describe this, but when you mate a nearly massless planar to a "heavy" cone driver, can the cone move fast enough to match the planar (is this phase alignment?). I know that ESL's do this commonly but that is usually below ~100-150hz as sub-duty, will I run into any problems crossing at 500-700hz.
Before this gets too long... if anyone would like to bring up any thoughts or ideas, positive or negative on this plan feel free. It seems logical to me, but that's not experience talking.
BTW, Im looking to eventually build 5 speakers (HT obviously), Im going to start with two to test the design, if anyone even recomends this design, should I build all 5, or at least the fronts and center identical.
Thanks in advance
Hello all,
First off I am new to this hobby so bear with me.
The plan, simply stated above is what I am thinking, enclosed in a transmission line of course. Now from what I have read 2-way systems are simpler, especially for a newbie but will cost about the same if you want deep bass extension, so that is the goal. However, $63 a piece for the planar, I might want to go 3-way. On the flip sied, from reading other posts, it seems desirable to avoid having a crossover in the critical region based on the Fl/Mun. curves, hence the B&G's that cover 500hz up to 20k and the dual 8's should only be a couple dB's down in the high 20's (hz) which is fine.
Now part of my question is does anyone have any experience with these B&G's (partsexpress 264-712)?
The other part and I dont know the technical term to describe this, but when you mate a nearly massless planar to a "heavy" cone driver, can the cone move fast enough to match the planar (is this phase alignment?). I know that ESL's do this commonly but that is usually below ~100-150hz as sub-duty, will I run into any problems crossing at 500-700hz.
Before this gets too long... if anyone would like to bring up any thoughts or ideas, positive or negative on this plan feel free. It seems logical to me, but that's not experience talking.
BTW, Im looking to eventually build 5 speakers (HT obviously), Im going to start with two to test the design, if anyone even recomends this design, should I build all 5, or at least the fronts and center identical.
Thanks in advance
(sorry for my english)
Hi,
If you are a"newby"without a measurements-set I think the mission
is not easy possible!
Indeed your idea is good but you want too much......🙂
Look at the htguide.com forum , in the section "mission possible.."
there is a thread " Arvo part III heavy metal testing" page 9.
Jon Marsh have posted a frequency response of the Neo8 mounted in a very big baffle ( quasi half-space I presume). Are you Ok to take that curve and to simulate the behaviour in your baffle-cabinet?
Sure , it is possible x-over 600-700 Hz 2nd order minimum (electrical).
Again, two 8" in TL. One is not enough?
A closed-box is easy, a TL not.
Dayton classic: maybe a Perless CSX ( or Vifa ) can be considered,IMO.
Obiouvsly this is only my opinion, but I hope can help you.
Regards,
Hi,
If you are a"newby"without a measurements-set I think the mission
is not easy possible!
Indeed your idea is good but you want too much......🙂
Look at the htguide.com forum , in the section "mission possible.."
there is a thread " Arvo part III heavy metal testing" page 9.
Jon Marsh have posted a frequency response of the Neo8 mounted in a very big baffle ( quasi half-space I presume). Are you Ok to take that curve and to simulate the behaviour in your baffle-cabinet?
Sure , it is possible x-over 600-700 Hz 2nd order minimum (electrical).
Again, two 8" in TL. One is not enough?
A closed-box is easy, a TL not.
Dayton classic: maybe a Perless CSX ( or Vifa ) can be considered,IMO.
Obiouvsly this is only my opinion, but I hope can help you.
Regards,
inertial said:
First off, thanks for the reply, your the second, the first person replied who used a single neo8 crossed at 700hz to two 6.5" vifa's, I dont know the f3 of his system.
Out of curiosity, how am I wanting too much? Is that not why we are here?😀
The measurement set that I have is speaker workshop and a good microphone, most people seem to get by with this hopefully I will too.
I read the article you mentioned, they are building line arrays and they seem to be fairly impressed with them with the exception of the on-axis roll off at 18khz and the beaming in the 6khz and up range, this Im not too happy to see, but is the loss of dispersion acceptable with the benefit of a wide range low distortion driver?
You asked why 2, I decided on two to match efficiencies, the woofers are about 3 dB below the neo8, doubling up should match them nicely.
Why a TL, sound quality of course, just so you know Im not new to woodworking, and Im going to use solidworks to model the enclosure before I start cutting. This project is partly a learning experience and I want to gain experience tuning a tL enclosure.
(I have an idea for a varialbe length and therefore tunable TL, and I want to see how it works)
I picked the Daytons over the others for the low end extension, this is basically the only reason, at the time I didnt think of transient response or distortion, which is not advertised anyway.
Im looking to get low bass, an f3 at or below 30hz would make me happy, would the peerless csx or the vifas do this?
Hi nunayafb,
Oh, I am sorry but maybe I had understood wrong!
You have MLS, you are familiar with x-overs,you are familiar with woodworking and you know TL theory . Very well.
You are an expert,not a "newby"!
Anyway IMO the woofers are not at the same quality-level of the Neo8.
The single 8" TL recall me the Clements. Nice.
Double 8".
What do you think about a 2.5 ways?
What do you think about a filter a la John Bau (Spica) or a la John Kreskowsky?
Be ware with the Neo8 : it start as pointsource and ....finish as linesource.
Best experimentations!
Cheers,
Oh, I am sorry but maybe I had understood wrong!
You have MLS, you are familiar with x-overs,you are familiar with woodworking and you know TL theory . Very well.
You are an expert,not a "newby"!
Anyway IMO the woofers are not at the same quality-level of the Neo8.
The single 8" TL recall me the Clements. Nice.
Double 8".
What do you think about a 2.5 ways?
What do you think about a filter a la John Bau (Spica) or a la John Kreskowsky?
Be ware with the Neo8 : it start as pointsource and ....finish as linesource.
Best experimentations!
Cheers,
well I guess we have something in common: we want to use the awesome NEO planar driver for great mid/hi frequency coherence. Further, I'm building FIVE, count 'em, five for a Home theatre project, each with a NEO and what I've outlined below.
Have you considered bi-amping your project? That may solve some, if not all your problems. Especially with the low-end. You'll pick up some of the speed you need to keep up with the NEOs. Read on, you'll see I love bi-amping and I have tri-amping in mind.
I plan to cross it over to two 5.25s or two 6.5s for mid bass and then cross those over to my subs. Still in the market for the mid/bass drivers.
The one problem I want to solve with minimal (electronic) help is that frequency taper below 1Khz.
Thanks for reading this far
Tony
Have you considered bi-amping your project? That may solve some, if not all your problems. Especially with the low-end. You'll pick up some of the speed you need to keep up with the NEOs. Read on, you'll see I love bi-amping and I have tri-amping in mind.
I plan to cross it over to two 5.25s or two 6.5s for mid bass and then cross those over to my subs. Still in the market for the mid/bass drivers.
The one problem I want to solve with minimal (electronic) help is that frequency taper below 1Khz.
Thanks for reading this far
Tony
Thanks for the reply, I thought briefly about bi-amping but I have one 7.1 receiver right now and will not be doing any amp building for awhile.
In addition, I want to gain experience with crossover design and implementation.
I spoke to a guy (email) who used two 6.5's w/ a neo and loved it, I chose the two 8's for bass extension, I will use the sub (18"fosgat sub in ~6 cube box) for movies but for music I want clean Tl type bass, flat to 30hz. I'll see how it goes.
As for building the 2 for surround, I would not recommend it,
1. it will be expensive.
2. From what I have read and heard,( various sources) it is generally better to use a form of di(bi)pole cant remember which, the one that uses double the amount of drivers out of phase. "This makes it harder to locate the surrounds to give a better effect", (dickason) not an exact quote but you get the idea.
I too will be using them for the LCR channels, and cannot wait to build them. I have not bought them because B&G might release the neo10 for diy, which is supposed to be so much better, and will extend to ~150hz.
BTW are you considering open baffle or boxed, I have been pondering OB but, Have not decided.
In addition, I want to gain experience with crossover design and implementation.
I spoke to a guy (email) who used two 6.5's w/ a neo and loved it, I chose the two 8's for bass extension, I will use the sub (18"fosgat sub in ~6 cube box) for movies but for music I want clean Tl type bass, flat to 30hz. I'll see how it goes.
As for building the 2 for surround, I would not recommend it,
1. it will be expensive.
2. From what I have read and heard,( various sources) it is generally better to use a form of di(bi)pole cant remember which, the one that uses double the amount of drivers out of phase. "This makes it harder to locate the surrounds to give a better effect", (dickason) not an exact quote but you get the idea.
I too will be using them for the LCR channels, and cannot wait to build them. I have not bought them because B&G might release the neo10 for diy, which is supposed to be so much better, and will extend to ~150hz.
BTW are you considering open baffle or boxed, I have been pondering OB but, Have not decided.
B & G Dipole
I have the xo schematics for this dipole design, and some text, that unfortunately is in German and a scan so not Google translatable. I am very interested in this design, but lack the time to build a pair. The woofers are discontinued but I would guess a similar spec could be found. I can send scans if you are interested. Its a bit complex but may be of help.
http://www.audax-speaker.de/pro30d.htm
amt
I have the xo schematics for this dipole design, and some text, that unfortunately is in German and a scan so not Google translatable. I am very interested in this design, but lack the time to build a pair. The woofers are discontinued but I would guess a similar spec could be found. I can send scans if you are interested. Its a bit complex but may be of help.
http://www.audax-speaker.de/pro30d.htm
amt
Dipole x-over
I would love to see a copy of the x-over for that design, as I have been interested in that design for some time. Could you post it here or email it to me. Thanks.
I would love to see a copy of the x-over for that design, as I have been interested in that design for some time. Could you post it here or email it to me. Thanks.
dtaylo3
The jpg is too big to post, and compacting it renders it illegible. So I will email you both the schematic and the text.
Good luck
amt
The jpg is too big to post, and compacting it renders it illegible. So I will email you both the schematic and the text.
Good luck
amt
Have been experimenting with the Neo 8's in a car stereo setup.(ok,back off you purists!) Have tried crossing them over at 700 and I am getting some distortion at high levels.Also,after looking closer at the specs,they start rolling off around 1k.I will be raising my crossovers up to 1k and will let you kno what happens.
I would also be interested in the crossover schematic.(Will be building a home setup soon.)
I would also be interested in the crossover schematic.(Will be building a home setup soon.)
Hey nunayafb!
Let me apologize up front for my longwinded reply. I down loaded your thread & then spent time studying and writing as the day wore on.
Check the B&G Neo8 Measurements thread elsewhere in this forum; that will give you some info. I'm curious to see the frequency response with a different size chamber.
On another note it’s been awhile since I’ve been on this forum. I’m still interested in building a HT system with similar speakers you mentioned, namely the Vifa system w/ BGs in your first counter-reply to the first one you received.
I've been looking at successful projects on the ‘Net similar to what I have in mind. If I like their results in the range that I want to use this or that driver, I know I should get similar if not better results as I’m bi-amping with 4th order filtering.
We both would like to XO the Neo around the same frequency. We’re both concerned about speed. That is, we both building systems using a driver, the Neo, that is very light and, hence, very fast, and woofers that may or may not be. In my case I’m depending upon my subs to handle the last couple of octaves. This allows me to use smaller, and consequently Lighter and FASTER drivers for the mid-bass. For this reason one driver spec to consider, if available which comes under several names is, cone mass, cone weight, or moving mass. Lighter is faster!! Lighter, unfortunately, depending upon material, is usually less rigid. So choose carefully. If “your” low end can’t keep up with the BGs, snare drums and tom toms, for example, won’t have quite the attack and percussiveness they otherwise could. In other circles they'll say things like "smeared image." The lower you XO them, the less this may matter.
You may want to consider an array of three or more smaller drivers. Every time you double number of drivers, output goes up by 3dB* and distortion goes down especially in the lower registers of their range. If my prototype center speaker, with two, doesn’t “cut the mustard” I may go that route myself with 4 5.25”. Right now I’m still in the decision stage on which amps to build to drive it. And, as of the reading of your mention of the Neo 10, waiting for its release.
* with the same power input.
* without using either EQ or notch filtering
** I'd XO them around 400 hz if I felt it were practical
On that note, you should read up on Stepped Baffle compensation (SBC). One place is http://trueaudio.com/st_diff1.htm. Another is http://www.sound.westhost.com. Look for the article and project by the same name. SBC may agravate the frequency response issues.
To carstereogeek:
Thanks for reading this far; your comments please!
Tony
Let me apologize up front for my longwinded reply. I down loaded your thread & then spent time studying and writing as the day wore on.
Check the B&G Neo8 Measurements thread elsewhere in this forum; that will give you some info. I'm curious to see the frequency response with a different size chamber.
I'm with you on this! Most people into DIY are not satified with what's available.
On another note it’s been awhile since I’ve been on this forum. I’m still interested in building a HT system with similar speakers you mentioned, namely the Vifa system w/ BGs in your first counter-reply to the first one you received.
I've been looking at successful projects on the ‘Net similar to what I have in mind. If I like their results in the range that I want to use this or that driver, I know I should get similar if not better results as I’m bi-amping with 4th order filtering.
I’ll take any link, email, phone number, etc., to get more info on that Vifa system. I may, but don’t necessarily plan to, use Vifas. I may, like you, use Daytons! (5.25", 6", or 6.5"). Because I may build up to 8 of these speakers, $ partially governs Dayton VS Vifas VS Peerless, etc. Sound quality ultimately has the “stronger say” in this decision. I hope BG releases the Neo 10 you speak of soon making my mid-woofer selection easier.
The “.1” circuitry will handle everything below 80-100 Hz depending on the decoding available (THX, DTS, Pro-logic II, etc.) IF you set your receiver to use the sub/LFE channel. Hence, your F3 below 50 Hz isn’t that critical if you ultimately plan to add a sub/LFE speaker. If it sounds great without a sub/LFE, it will really sound awesome with!! Plus your system will play louder w/much less distortion to boot! Finally if your receiver has pre-amp outs and power amp inputs you could still use the internal amps somehow and somewhere in your system!
We both would like to XO the Neo around the same frequency. We’re both concerned about speed. That is, we both building systems using a driver, the Neo, that is very light and, hence, very fast, and woofers that may or may not be. In my case I’m depending upon my subs to handle the last couple of octaves. This allows me to use smaller, and consequently Lighter and FASTER drivers for the mid-bass. For this reason one driver spec to consider, if available which comes under several names is, cone mass, cone weight, or moving mass. Lighter is faster!! Lighter, unfortunately, depending upon material, is usually less rigid. So choose carefully. If “your” low end can’t keep up with the BGs, snare drums and tom toms, for example, won’t have quite the attack and percussiveness they otherwise could. In other circles they'll say things like "smeared image." The lower you XO them, the less this may matter.
You may want to consider an array of three or more smaller drivers. Every time you double number of drivers, output goes up by 3dB* and distortion goes down especially in the lower registers of their range. If my prototype center speaker, with two, doesn’t “cut the mustard” I may go that route myself with 4 5.25”. Right now I’m still in the decision stage on which amps to build to drive it. And, as of the reading of your mention of the Neo 10, waiting for its release.
* with the same power input.
I’m not familiar with OB. Are you referring to how to load or baffle the BGs? If so my answer is whatever best fills in the frequency dip between 600 hz & 1K hz without messing up imaging and phase I'd do it. In fact if I could find a way to load them to actually have more output* below 6k-8K hz to the XO point**, than that peak I'd do it! Again I refer you to the “B&G Neo8 Measurements” thread.
* without using either EQ or notch filtering
** I'd XO them around 400 hz if I felt it were practical
On that note, you should read up on Stepped Baffle compensation (SBC). One place is http://trueaudio.com/st_diff1.htm. Another is http://www.sound.westhost.com. Look for the article and project by the same name. SBC may agravate the frequency response issues.
To carstereogeek:
@ What slopes are your BGs XO’d? You may, depending upon your power levels, mid-woof choice and/or XO slope, be hearing midrange cone breakup or the BGs are getting too much bass or all the above.
Thanks for reading this far; your comments please!
Tony
Hi amt,
Could you plese send me a copy of the cross over?
Thanks.
Ashok.
amadhavan( at )eth.net
Please change the ( at ).
Could you plese send me a copy of the cross over?
Thanks.
Ashok.
amadhavan( at )eth.net
Please change the ( at ).
gp4Jesus-
I'm using 2nd order LR crossovers.Could be I need to go to 4th order? I,m putting 60 watts a piece to the BG's and the 5 1/4" mids.Could also be too much power to the BG's!
Thanks for the reply.Haven't had too much responce in the car stereo forum.
I'm using 2nd order LR crossovers.Could be I need to go to 4th order? I,m putting 60 watts a piece to the BG's and the 5 1/4" mids.Could also be too much power to the BG's!
Thanks for the reply.Haven't had too much responce in the car stereo forum.
crossover schematic
amt, I would really appreciate it if you would email the crossover document to me as well. I have a pair of GR research Alpha LS speakers that I built over a year ago. They use 8 Neo 8's per side. They sound fantastic but are a little rolled off at the extreme high end. I would like to try putting a single Neo3 in the middle of the Neo8 array . My email is nancybert@shaw.ca
amt, I would really appreciate it if you would email the crossover document to me as well. I have a pair of GR research Alpha LS speakers that I built over a year ago. They use 8 Neo 8's per side. They sound fantastic but are a little rolled off at the extreme high end. I would like to try putting a single Neo3 in the middle of the Neo8 array . My email is nancybert@shaw.ca
you are kidding right?
Just in case anyone cares, the plans have changed, the classic woofers have been replaced with two rs225 woofers, which will go into a transmission line, and the neo8 will be dipole with a neo3 to top it off and negate the need for a sensitivity robbing notch filter. Not sure if the neo3 will be dipole yet or not, might experiment, might ask the people at the B&G forums.
To be honest, I was not happy with what I saw when I opened the neo's up. Having done some sheetmetal work in the military I know how simple this kind of structure is and someone is making a killing off of these, $62!!! They are so simple that im not worried about quality, or tolerances or anything but dang, cheap rivets visible from the front, conducters/kaladex in the screw holes ( not connected to the signal path im sure), these are definately mass produced cheaply. Im definately going to be building my own planars now. I was wondering why the FR was so ragged, hmmm maybe someone spent more on marketing than R&D.
Anyways Ill let you know how they turn out😎
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