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Open Baffle Design....Very early doors!


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17 minutes ago, mattjtaylor2809 said:

Looking at the SPL Vs Frq charts, the Silver 8 chart doesn't look that great with a dB diff of 20+ between 20-100 Hz whereas the Crystal 10 only seems to have a variance of about 10 dB for the same frequency range?

 

Crystal 10 $999 US Pair - only 10 dB diff between 20-10 Hz & nice flat curve thereafter.

They do suggest best driven via low power tubes but I have Rogue Audio M-180 monoblocks @ 180 watts ea. side?

 

image.png.7d8f7e347a103b78a71a311a9ba11080.png

 

 

Silver 8 - $399 Pair - 20 dB diff between 20 - 100 Hz

 

image.png.570f4fb3ccf4051f5392acf4b5714e99.png

 

 

F-15 Full Range Driver - $399 pair - also roughly 20 dB diff between 20-100 Hz

 

image.png.5d0e19debd2bc87913a142fa60400a04.png

 

Finally, this is the range in dB of the W-15 woofer

 

image.png.5e7a7440f17057f60a3d09132c9b6d4b.png

 


Maybe all this doesn't matter when in combination with the F15 & with his XO?

 

I'd prefer a 10 - 15" full range driver to complement with woofer but the Silver 10 at $1,199 US is starting to become a bit too expensive for a "side project" but as he says in the article, they are exchangeable as the XO will support all combos?

 

Am I looking at the wrong things?

 

Cheers

Matt

 

 

Supposedly the Silver 10 sound noticeably better than the Crystal 10 in his baffles. I only know what he's posted online.

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Hi All,   I trust everyone had a great Christmas? Mine was a little scary as my Dad had a turn which required a trip to hospital & a pacemaker implanted 24 hours later but he's all goo n

Hi all,   Thanks for all your posts, so much to learn.   Here are some pictures from today’s efforts.           Will build the

I've recently built my first open baffle project being the "lionidas" using W15 woofer and Fast 8 (wide band) drivers. In my room they measure to 30Hz before dropping off which is quite the feat for a

I've recently built my first open baffle project being the "lionidas" using W15 woofer and Fast 8 (wide band) drivers. In my room they measure to 30Hz before dropping off which is quite the feat for a passive crossover open baffle design.  

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3 hours ago, gemini07 said:

 

Not me - no. I'm quite happy with what I have. They do the job for both stereo and HT.

Yeah I'd love some but very hard to come by.  Anyhoo,  enough of my off topic questions

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A little taste...

 

image.thumb.jpg.9c6b160037628f6c4ee590e0d80f3acf.jpg

 

8” full range driver in very rudimentary OB design.

 

Very impressive immersive sound with such a wide vocal.

 

Not the last word in bass response but much better than you would think,

 

Adding a 15” woofer will sort that ?

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Having been playing with OB designs for a number of years I think that the best bass comes from at least 2 X 15 inch drivers mounted in a V located in the middle of the other drivers.

That location will not be an easy sell but I think it is the best.

An issue with that is that the connections for the channels need to be swapped side to side, LH channel bass to the RH bass speaker and RH channel bass to the LH bass speaker.

I know it sounds weird to wire this way but it is easy to try but worth the effort.

P1020178.JPG.2677fd8d2fefa6e441ae4849265ee466.JPG

 

The use of a miniDSP or similar will also aid in getting the frequency response, levels and phase to be more easily sorted rather than using passive components.

 

Try to use drivers that need little or no crossover components (natural roll offs) and are of high efficiency.

 

I wish you well in your endeavours, the effort in getting an OB system up and running, is in my opinion very worthwhile.

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Here is a photo of my speakers using an inferior Passive crossover design of a proffesional speaker designer Leon Huijgen. The design can be found 

http://www.modelpromo.nl/The Liiondias Open Baffle Speaker.htm or on facebook group Lii Audio Hifi Drivers & Speakers Team or on Leons FB posts.

 

image.thumb.png.6a73fd832a02420eec5164974b309a26.png

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5 minutes ago, niss_man said:

Here is a photo of my speakers using an inferior Passive crossover design of a proffesional speaker designer Leon Huijgen. The design can be found 

http://www.modelpromo.nl/The Liiondias Open Baffle Speaker.htm or on facebook group Lii Audio Hifi Drivers & Speakers Team or on Leons FB posts.

 

image.thumb.png.6a73fd832a02420eec5164974b309a26.png

I'd not call passive inferior at all, though I know there are those that do.

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Righteo....here goes me being stoopid.

 

image.png.ac03287d3f8945ce68c591205dfda4fb.png

 

Basics...

 

I'm assuming an Inductor (to reduce HF going to the woofer?)

I'm not sure how to read the specs, is x5 6mH....Low RDC??

 

image.png.220cc5976eb691112e4059cce0a17ecc.png

 

 

These are Capacitors? (reducing low freq to tweeters)?

 

image.png.cd826d99cdb5a5bc349545291367db6a.png

 

Are these then depicting resistors? (reducing the amount of power directed to each speaker)?

 

Is this saying x1 1.2Ohm or is it x1 2 Ohm?

image.png.4deba52b353ada73731c628990cffeaa.png 

 

x6 8 ohm....20 watts?

image.png.dc38799673ad3ec2dd839625a0b463cf.png

 

 

The schematic also suggest this design has x2 woofers or is this just a dipole design of the W-15 which has x2 different binding posts?

 

image.png.6986ea06fac8329b817030897a313fb4.png

 

Finally, is this suggesting there is a 2nd tweeter....I don't see this in the pictures of the actual speakers?

 

image.png.46e4116dc3ae5e8025e6c2529c497528.png

 

 

As I said, I'm a newby at this, I enjoy the learning though.

 

Cheers

Matt

Edited by mattjtaylor2809
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With Silver 10 or Crystal 10, no ambient tweeter required.  Using Fast-10S, Fast-10B, F12 or F15 though....Different story.

 

The cost of quality tweeters at the level of the Lii Audio drivers can quickly make up much of the price difference of just going for the Silver 10 drivers in the first place. Especially if using Duelund Cast as I am.

 

I had not originally planned to use tweeters in my speakers,  they were added afterwards after finding a deficiency in treble from around 12k. Cheaper to just go the top Lii Audio drivers in the first place. I wish I had done so.

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I don't plan to add an ambient speaker.

 

Did you buy most/all of your XO components from Duelund?

 

https://duelundaudio.com/inductors/

 

I ask as they state the following for their CAST Capacitors & the XO design states 68uF....did you have these specialty designed?

 

"Standard sizes 0.001 uF – 50 uF other values available on request."

 

 

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18 minutes ago, mattjtaylor2809 said:

I don't plan to add an ambient speaker.

 

Did you buy most/all of your XO components from Duelund?

 

https://duelundaudio.com/inductors/

 

I ask as they state the following for their CAST Capacitors & the XO design states 68uF....did you have these specialty designed?

 

"Standard sizes 0.001 uF – 50 uF other values available on request."

 

 

I'm only limiting my tweeters with a single 2.2uf cap per tweeter. Even so on sale at half price that set me back about 700 clams.

 

I did this after experimenting with many different caps. They really do all sound different.  The Duelund allowed the tweeters to blend seamlessly to my ears.

 

My W15 woofers have their own amp and currently run full range though I am considering moving to an amp will allow me to limit what frequencies go through to the woofers. I guess you could say part passive crossover and part active.

Edited by MattyW
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Dipole andOpen baffle are being used interchangeably in this thread, but they are not the same thing.

 

To get dipole radiation from an open baffle you need progressively narrower baffles as the FR rises.

 

This is why the Linkwitz LX521, Kyron speakers and similar designs have the baffle shapes (or lack of baffle) they do.

 

Wider baffle speakers like Spatial are only dipole up to about 1000Hz.

 

Basically, the wider the baffle the lower the dipole effect.

 

You still get the benefits of having no baffle, and of having rear radiation.

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23 hours ago, mattjtaylor2809 said:

I think I’ve downloaded this specs for this design.

 

which full range driver did you pick, you happy with the overall sound, bass response?

Hi Matt

 

I bought the Fast 8 drivers to go with the W15. Using original the original xover from leon I found it not to be optimal as it was originally designed to use the Crystal 10 widebands. I have been testing different mods to the crossover to get better sound.

 

Using an LCR notch filter in parallel with the W15 helped reduce the excesive energy in the 100 - 300Hz region. That energy is a result or the dipole radiation. As can be seen when measuring and also "The Edge" baffle diffraction software.

 

image.png.5be29054cbc056b0ccb9aadd56412f1b.png

 

Doing that produced slightly excessive bass but much better overall sound. So I change the 6.8ohm tweeter resistor to 5.6ohm and that seems perfect for me and these speakers now.

I also have some "Noema" Russian wideband drivers coming at some stage for me to try in replacement of the Fast 8's although those may need a helper tweeter as well.

image.png

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23 hours ago, mattjtaylor2809 said:

Basics...

 

I'm assuming an Inductor (to reduce HF going to the woofer?)

I'm not sure how to read the specs, is x5 6mH....Low RDC??

 

image.png.220cc5976eb691112e4059cce0a17ecc.png

 

In short , Yes. But! the crossover is of a series type (tweeter and woofer in series) so the inductor will also affect the tweeter. As the inductor is decreased, more high frequency energy will pass to the woofer and also less low frequencies will pass to the tweeter/ wideband driver. Vice versa if incrasing the inductor  value. 

The designer is asking for a low DC resistance (resistance measured with a multimeter) inductor.

 

23 hours ago, mattjtaylor2809 said:

These are Capacitors? (reducing low freq to tweeters)?

 

image.png.cd826d99cdb5a5bc349545291367db6a.png

In short yes, but again this affects both drivers because of the series crossover. As the capacitor value decrease, the tweeter receives less low frequencies at the same time the woofer receives less high frequencies. 

 

23 hours ago, mattjtaylor2809 said:

Are these then depicting resistors? (reducing the amount of power directed to each speaker)?

 

Is this saying x1 1.2Ohm or is it x1 2 Ohm?

image.png.4deba52b353ada73731c628990cffeaa.png 

 

x6 8 ohm....20 watts?

image.png.dc38799673ad3ec2dd839625a0b463cf.png

Yes an open rectamgle represent a resistor on a electrical schematic also you may see them as a squiggly line as used in USA.

The first is a 1.2ohm resistor. In europe they like to use commas instead of full stops.

Yes 6.8 20W recommendation although I use a 10 w easily with no excessive heating of the resistor, and I play music quite loud. I'd hate to be sitting in the room when playing at a volume level to start heating a 10w resistor excessively.

 

23 hours ago, mattjtaylor2809 said:

The schematic also suggest this design has x2 woofers or is this just a dipole design of the W-15 which has x2 different binding posts?

 

image.png.6986ea06fac8329b817030897a313fb4.png

It is a dual voice coil woofer (1 woofer 2 coils) wired in parrallel. It has a minimum of 3.4ohm impedance when wired as such.

 

23 hours ago, mattjtaylor2809 said:

Finally, is this suggesting there is a 2nd tweeter....I don't see this in the pictures of the actual speakers?

 

image.png.46e4116dc3ae5e8025e6c2529c497528.png

 

 

As I said, I'm a newby at this, I enjoy the learning though.

 

Cheers

Matt

Depending on what wideband driver is used and what your preference is as to whether you add a helper tweeter. Leon's can be seen on this photo 

1253648360_helpertweeter.jpg.160a1ee061b75c3f73a4691c05941374.jpg

 

Cheers

 

Simon

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23 hours ago, mattjtaylor2809 said:

I don't plan to add an ambient speaker.

 

Did you buy most/all of your XO components from Duelund?

 

https://duelundaudio.com/inductors/

 

I ask as they state the following for their CAST Capacitors & the XO design states 68uF....did you have these specialty designed?

 

"Standard sizes 0.001 uF – 50 uF other values available on request."

 

 

I used purely Jantzen components sold by Speakerbug in Brisbane. I can give nothing but high praise when dealing with Nigel from speakerbug over the years.

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12 hours ago, Lazz said:

I have 8 of these babies waiting for an ob design. I gotta get the saw dust flying soon.?

8... I havent heard the dipole 15's but have heard others AE's in sealed boxes. They are fantastic drivers. The Dipole 15's have great specs for use in dipole config so should go great guns.  Your going to geat great efficiency using 8 which is what I guess you are going for.

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Just now, niss_man said:

8... I havent heard the dipole 15's but have heard others AE's in sealed boxes. They are fantastic drivers. The Dipole 15's have great specs for use in dipole config so should go great guns.  Your going to geat great efficiency using 8 which is what I guess you are going for.

Yes, thats the idea. 2 designs I am tossing around are the Kyron Audio Gaia - with 4x15 per side or the Pure Audio Project Quintet style. Still haven't decided yet. 

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Thanks for everyone’s posts, I’m just trying to digest everything.

 

Is there a definition for an OB speaker Vs dipole speaker? I’m getting a little confused/ mixed up?

 

Thanks for the heads up with Speakerbits, I’ll chase them up shortly & discuss options as the XO design above is pretty basic & I may tweak it a bit based on feedback on here etc.

 

@niss_man thanks for spending the time to better explain the XO components & design, it’s helping to better understand the interplay between components.

 

Keep the posts, ideas coming.

 

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As far as I understand, dipole speakers radiate the same energy forwards and backwards. Similar to open baffle..except some open baffles may have a (just an example here) tweeter that has a closed back and so radiates it's energy toward the listener only and not behind as it has a closed back. If you use a dipole ribbon (open back and front) then that would become a dipole speaker as the same sound that emits forward does so backwards as well. Some thing like these apogees are true dipole ribbon speakers

 

Apogee Duetta Signature | HFA - The Independent Source for Audio Equipment  Reviews

 

Something like these pure audio project speakers arent "true" dipoles as it has a horn tweeter which only radiates towards the listener and not behind.

Home, Open Baffle Speakers - PureAudioProject

 

Usually the term open baffle and dipole are used interchangably although there are differences.

Now the difference in sound between the 2 ? Thats something I wouldn't bother commenting on as I've heard heaps of speakers over the years and all can sound good or bad depending on implementation but as a general statement I do find open baffle/dipole bass to have less "room" interactions and therefore in general tend to give more insight into the bass sounds.

 

May I suggest downloading somthing like "xsim" (free) and some frd files (frequency response) and zma (impedance files) of drivers to easily see what is happening when you design your own crossovers. 

 

By the way, Jantzen australia distributor is speakerbug not speakerbits. https://speakerbug.com.au/

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14 hours ago, niss_man said:

As far as I understand, dipole speakers radiate the same energy forwards and backwards. Similar to open baffle..except some open baffles may have a (just an example here) tweeter that has a closed back and so radiates it's energy toward the listener only and not behind as it has a closed back. If you use a dipole ribbon (open back and front) then that would become a dipole speaker as the same sound that emits forward does so backwards as well. Some thing like these apogees are true dipole ribbon speakers

 

Apogee Duetta Signature | HFA - The Independent Source for Audio Equipment  Reviews

 

Something like these pure audio project speakers arent "true" dipoles as it has a horn tweeter which only radiates towards the listener and not behind.

Home, Open Baffle Speakers - PureAudioProject

 

Usually the term open baffle and dipole are used interchangably although there are differences.

Now the difference in sound between the 2 ? Thats something I wouldn't bother commenting on as I've heard heaps of speakers over the years and all can sound good or bad depending on implementation but as a general statement I do find open baffle/dipole bass to have less "room" interactions and therefore in general tend to give more insight into the bass sounds.

 

May I suggest downloading somthing like "xsim" (free) and some frd files (frequency response) and zma (impedance files) of drivers to easily see what is happening when you design your own crossovers. 

 

By the way, Jantzen australia distributor is speakerbug not speakerbits. https://speakerbug.com.au/

 

Yeah, mine are a bit like that in that my Aurum Cantus G3Si ribbons are closed back and forward facing. I also have some bullet tweeters firing up at the ceiling to get around this a bit making them omni directional despite also being closed back as they're basically compression horns. This ensures the speakers sound good from litterally anywhere including standing beside or behind the speakers.

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Hi All,

 

Been a bit busy at work but have been doing some research

 

I've been receiving some helpful advice on the XO from a Nigel at Speakerbug in Qld (Thanks @niss_man for the recommendation).

 

I've also emailed Lii Audio for pricing & delivery times into Adelaide for their W-15 woofers & possibly the Fast-8 (or Silver-8) full range driver but I've not heard back from them so I'll hit them up on their FB page. If I do use the Lii Audio Fast-8 (Crystal 10 too expensive for me at the moment), as posted above, this the recommended 2-way XO:

 

image.png.5dc9051ffb5e00457c5a23baf7270baa.png

 

In terms of parts for this set up, I'll will most likely use the following:

 

Jantzen CrossCap $35 ea Capacitors (next step up is the Standard-z at $85 ea).

https://speakerbug.com.au/index.php?route=product/category&path=25_73

 

Nigel suggests that you can run a Cornell bypass capacitor in parallel (see below) which will create an overall more mature/natural sounding speaker....& cheaper than the next step up.

image.png.a7b3ac8b4929e6e84c9d80e6b8754fb7.png

 

Jantzen P-Core 5.6mH 15AWG (0.25 Ω) Inductor at $35 ea.

https://speakerbug.com.au/index.php?route=product/product&path=18_45&product_id=881

 

Superes 10 watt 2.2Ω & 6.8Ω Resistors

https://speakerbug.com.au/index.php?route=product/category&path=33_27

XO design suggest 20 watt but others have said 10 watts ok....can also run in parallel to increase to 20 watt.

I'll also buy some silver coated tin speaker wire plus binding posts & I'm done!

 

 

BUT.......if I don't use the Lii Audio Fast-8 speaker & use Aurel Bryan fullrange 8" drivers.....does this change the specs for this speaker or the entire XO?

 

image.png.563a1f14faf1d397a60d5e5573d56886.png

 

The specs on the Aurel Bryan (FR8DFe-Mk2) 8" Full Range Speakers are:

 

image.png.8687a31dd29d3f5353a5c297ab80cb90.png

 

Fast 8 Specs

 

image.png.a8b04aba25e94ecf704f969328f3bf69.png

 

Whilst I don't understand all (most ?) of the measurements, they do look quite different so I'm assuming the XO design may have to change if using the Aurel Bryan speakers?

 

Any suggestions, please let me know.

 

Cheers

Matt

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If this is your first attempt at building a pair of DIY speakers I would recommend sticking to a prebuilt design such as the leonidas or other diy kits. If you have the experience and knowledge as well as all the measuring tools and software tools and know how to use them then you would happily be able to mix and match drivers and also know what to change in the crossover to make it more suitable to your tastes. My recomendation if you are looking purely at open baffle design copy the Leonidas OB design as above.

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Hi Niss Man,

 

I hear you.....I will be using the Leonidas design although I've stupidly bought the Silver 8 not either the Fast 8 or the Crystal 10 so I will reach out to the designer for advice on any changes to the XO with this different full-range speaker.

 

I do have a group of interested & seemingly knowledgeable gents in the Adelaide Hills who will also be able too advise me.....kinda

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  • 2 weeks later...

Hi All,

 

I trust everyone had a great Christmas? Mine was a little scary as my Dad had a turn which required a trip to hospital & a pacemaker implanted 24 hours later but he's all goo now ?.

 

Things have moved on a bit since my last post as I've ordered the speakers & they arrived the other day.

 

Mate of mine @Grizzly had some left over 18mm MDF so we started to cut out all the parts for a Liionidas design OB (as I've posted above). I also bought some 18mm marine ply which we will use for the woofer baffle.

 

Thanks also goes to @Tony M for use of his workshop & tools....made short work of the cutting out of the MDF.

 

workshop.thumb.jpg.c7a96948a8ed5455715ba1dde732593b.jpg

 

Finished MDF & Marine Ply

 

Materials.thumb.jpg.d0593612c7db38708aae8f11ba12bef3.jpg

 

Silver 8's (thankfully I put the plastic bag back on them!)

 

545771522_Silver8.thumb.jpg.a96090e89ed866234a2d5da3c37a1d0b.jpg

 

Bonus 6" FR Drivers (I didn't order these??).

 

82513570_6FRDrivers.thumb.jpg.09639e880b1b9f5d0e555a267d0cf990.jpg

 

Massive 15" Drivers with my daughter for scale!

 

Woofer.thumb.jpg.078362809f1c629eb12cc418cdbeb500.jpg

 

Tomorrow I'll buy some cheapo XO parts just as a mock up before buying the "proper" parts (mainly Jantzen). We also need to take the cutting out of the baffles to house the speakers which will take some doing to keep it all neat but I'm sure if we take it slow, it will be ok.

 

I'll keep you all posted.

 

Cheers

Matt

 

 

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On 05/12/2020 at 5:18 PM, sfdoddsy said:

Dipole andOpen baffle are being used interchangeably in this thread, but they are not the same thing.

 

To get dipole radiation from an open baffle you need progressively narrower baffles as the FR rises.

 

No....   if we're being pedantic.

 

Dipole is simply where the is two approximately equal lobes forwards and backwards.   As wikipedia eloquently puts it a "dipole speaker in its simplest form cn be constructed by placing a loudspeaker on a flat panel".

 

What you are talking about..... is constant (horisontal) directivity  ...To achieve this in a dipole.... (as you said) it needs a baffle which narrows with frequency.

Edited by davewantsmoore
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The woofers (Lii Audio W-15) I'm using have been specifically designed for OB use & do have x2 voice coils so I'm assuming then they are dipole or nothing to do with it?

 

image.png.03f21c8a37210b40988c1fec2e913696.png

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No, Matt -  dipole refers purely to the soundwave direction - ie simultaneously front and back.  I'm not sure why those drivers have two voicecoils, but I don't think it's related to the dipole bit.  

 

EDIT  Aha! - here's an explanation of the 2 voice coils:

http://www.diy-audio.narod.ru/litr/DualVoiceCoilDrivers.pdf

 

Edited by Tony M
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9 hours ago, mattjtaylor2809 said:

The woofers (Lii Audio W-15) I'm using have been specifically designed for OB use & do have x2 voice coils so I'm assuming then they are dipole or nothing to do with it?

 

image.png.03f21c8a37210b40988c1fec2e913696.png

Hi Mattyjtaylor, did you write these schematics up? based on this: 

Audio Dandy - How to enjoy High Resolution Audio (modelpromo.nl)

 

how did you get on about the xo you're building? I'm working on building the same kit.  

cheers

 

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On 05/12/2020 at 2:12 AM, niss_man said:

Here is a photo of my speakers using an inferior Passive crossover design of a proffesional speaker designer Leon Huijgen. The design can be found 

http://www.modelpromo.nl/The Liiondias Open Baffle Speaker.htm or on facebook group Lii Audio Hifi Drivers & Speakers Team or on Leons FB posts.

 

image.thumb.png.6a73fd832a02420eec5164974b309a26.png

 

Hi Niss_man,

 

Nice work on the OB! And awesome noise treatment for that room (where did you get those purple panels and base traps?).

I'm waiting for my kit to arrive and will be building them up.  I went with Silver10 + W15.  

How is your Fast8 setup working ( sounding )for you?

When you say the passive cross over is inferior, in which way?  I'm newbie to DYI, I went this road in place of the PAP Duet15 with TangBand.   

cheers

hank

 

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11 hours ago, hank73 said:

Hi Mattyjtaylor, did you write these schematics up? based on this: 

Audio Dandy - How to enjoy High Resolution Audio (modelpromo.nl)

 

how did you get on about the xo you're building? I'm working on building the same kit.  

cheers

 


Hi Hank,

 

yes, pretty much following this design although I’ve bought the Silver 8 not Fast 8 or Crystal 10.

 

I’ve ordered the XO components but not received them as yet so will build XO later this week or weekend.

 

I’ll keep you all posted

 

Cheers Matt

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I think you'll be rather happy with the Silver 8. Meant to be significantly better than the Fast 8 though it's anyones guess how they compare with the Crystal 10.

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On 03/01/2021 at 4:00 PM, davewantsmoore said:

 

No....   if we're being pedantic.

 

Dipole is simply where the is two approximately equal lobes forwards and backwards.   As wikipedia eloquently puts it a "dipole speaker in its simplest form cn be constructed by placing a loudspeaker on a flat panel".

 

What you are talking about..... is constant (horisontal) directivity  ...To achieve this in a dipole.... (as you said) it needs a baffle which narrows with frequency.

Yes, I could have been clearer.

 

To maintain dipole radiation above a certain frequency requires the baffle to get narrower and narrower, ie Linkwitz LX521 and naked baffles like the Kyron.

 

Panel speakers like Maggies and Apogees, for example, are not dipole except at low frequencies. 
 

Even though I currently have OBs which do have narrowing baffles, the others I’ve owned or built over the past 20 years did not, yet still sounded more alike than different.

 

For me the big benefit of OBs is no box. A secondary benefit is front/back radiation that whilst not necessarily accurate is enticing.

 

The tertiary benefit of controlled dispersion and thus less room interaction is theoretically dandy, but very hard to achieve and even harder to objectively prove.

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Thanks for clarifying, it’s all new to me but I’m enjoying the learning.

 

BTW - The XO components arrived today & we will be cutting out the holes in the baffles, glueing the woofer baffles & possibly building the XO’s this weekend....as always, more to follow.

 

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BTW - any recommendations for a board to house the XO or just use mdf & cable ties to hold them together? 

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On 04/01/2021 at 11:44 PM, hank73 said:

 

Hi Niss_man,

 

Nice work on the OB! And awesome noise treatment for that room (where did you get those purple panels and base traps?).

I'm waiting for my kit to arrive and will be building them up.  I went with Silver10 + W15.  

How is your Fast8 setup working ( sounding )for you?

When you say the passive cross over is inferior, in which way?  I'm newbie to DYI, I went this road in place of the PAP Duet15 with TangBand.   

cheers

hank

 

HI Hank

 

The panels are made from bamboo fibres if I remember correctly found on ebay a few years ago. Same with the corner bass traps on ebay.  

I have found a bit of an issue with the crossover schematic. In that the fullrange driver is labeled in the wrong phase. This was apparant after using a 12" russian fullrange driver instead of the fast 8. The vocals sounded quite hollow, a bit set back (just not right).  Taking some measurements the next day did show this up quite easily in that there was a hole/dip in the 1-2.5k hz region. Swapping the polarity on the wideband driver fixed this right up.  It doesn't show up as much when using the fast 8 as the acoustic offset is a little differrent  but my ears could still pick up something that wasn't quite right.  Again measurements showed this to be the same case.

     It is sounding much nicer now but I still have a couple of things to try before deciding on the final circuit.

  My comment on passive crossovers being inferior is just my version of sarcasm at the active crossovers are the best and nothing else matters crowd.  It certainly has it's advantages but both can sound really good or really shite.

 

I recommend to have a quick listen to your silver 10's in both the original passive schematic design and then change polarity on the silver 10 to hear the differences. 

 

Cheers SImon

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