Advice? Single full range open baffle design?

[RockRolley]

1 hour ago, Full Range said:

I built a set for my son in law a few years ago 

My preference is larger diameter drivers 

However an active subwoofer would be beneficial if you play music with lots of bass 

 

Below is the build thread 

 

These look fantastic, well done. I've had a flick through, but I'll read in more detail soon

[crtexcnndrm99]

No worries. Enjoy discovering new sounds - speaker builds a so rewarding! The itch to build a FR just as you are planning is always there, but I really don’t need to

[Richieroo]

You could go with the Lii Audio F15 (just like in your example pics).

Apparently they work really well with low power tube SET amps (like Decware Zen Triode)

 

here's an example of the Lii F15 in an open baffle design: http://www.caintuckaudio.com/Lii_15.html

 

 

 

[RockRolley]

3 hours ago, Cideburns said:

You could go with the Lii Audio F15 (just like in your example pics).

Apparently they work really well with low power tube SET amps (like Decware Zen Triode)

 

here's an example of the Lii F15 in an open baffle design: http://www.caintuckaudio.com/Lii_15.html

 

 

 

Thanks for your input and feedback. I’ve read good things about Lii drivers. As far as contemporary drivers go, do you know how they compare with fostex? I’m sure I’ll have a try of these at some point. 

[Richieroo]

nah, I can't comment. I haven't heard them in the flesh (yet)

Steve Deckert has a few videos of his Zen Triode running the F15s running open baffle on the Decware webpage and on youtube

[Warren Jones]

I've used Mark Audio Alpair 12P in an OB for many years with subwoofer. I can tell you from experience if you go too large with the baffle imaging suffers due to the vibrations off the baffle. A baffle can have as much or more radiating surface than the driver depending on how large it is. With this baffle approx 400x380mm the 12P XO to the woofers at 250Hz

 

This setup the 12P is magnet mounted and the baffle is covered with felt to reduce vibrations off the baffle, but it didn't stop it, removing the baffle improved imaging.

 

The woofer cabinet uses 2x 12" Visaton woofers.

 

Don't get me wrong even these sounded pretty good and better than the Linn speakers I had a few years ago. These have been replaced by a set of Linkwitz LXminis that blew them away.

 

Edited March 7, 2022 by Warren Jones

[RockRolley]

35 minutes ago, Warren Jones said:

I've used Mark Audio Alpair 12P in an OB for many years with subwoofer. I can tell you from experience if you go too large with the baffle imaging suffers due to the vibrations off the baffle. A baffle can have as much or more radiating surface than the driver depending on how large it is. With this baffle approx 400x380mm the 12P XO to the woofers at 250Hz

 

This setup the 12P is magnet mounted and the baffle is covered with felt to reduce vibrations off the baffle, but it didn't stop it, removing the baffle improved imaging.

 

The woofer cabinet uses 2x 12" Visaton woofers.

 

Don't get me wrong even these sounded pretty good and better than the Linn speakers I had a few years ago. These have been replaced by a set of Linkwitz LXminis that blew them away.

 

Thanks for your input. It seems that people recommend a wide baffle in order to get sufficient bass out of the full range drivers, but you seem to have experienced a loss of imaging. To solve this, you've added woofers-is that right? As mentioned in my initial post, I get lost if I need to consider crossovers unless someone can point me to an available solution. It seems that your sub woofers are passive rather than active? I've never used an active subwoofer, but understand that does away with the need for a crossover. I'm open to adding woofers though for some reason reluctant to add powered subwoofer, but as mentioned also will get lost if I need to source a crossover for passive woofers without guidance. Do you have further recommendations regarding woofers? Thanks

[davewantsmoore]

1 hour ago, Warren Jones said:

reduce vibrations off the baffle, but it didn't stop it, removing the baffle improved imaging.

Small baffles also improve the directivity of the speaker.  

 

(where the baffle size is/was somewhere roughly the same size as the sound wavelength)

[davewantsmoore]

58 minutes ago, RockRolley said:

Thanks for your input. It seems that people recommend a wide baffle in order to get sufficient bass out of the full range drivers

 

A driver on an open baffle will not have a flat response.... what frequency the response is lacking will depend on the specifics (it will definitely lack bass, but could also be too low at higher frequencies too).

 

You have to do something to correct the response.   It could be:

 

1. Wide baffle

 

2. Driver with a peak in the frequency response due to the electro-mechanical system (eg. a "high Q" driver)

 

3.  A peak in the frequency response due to some sort of signal filter .... either a traditional "passive crossover"  (eg. a series indictor or similar, which pushes all the high frequencies down, thus increasing the lower frequencies relatively) ... or multiple sorts of "active" filters.

 

4.   Add more drivers to fill in the missing response.

 

Issues:

 

1.    Vibration.    Likely poor(er) direcitivty (which could sound like lack of clarity, or poor "image")

 

2.    The peak will be unlikely to be big enough or in the right place .... and the peak is often due to the bad performance of the driver motor (electro mechanical resonances)

 

3.   Is very powerful and flexible ... which means it can work well... but you can also make a very big and very wrong correction to the response and end up with "bad" sound.

 

4.   Needs to be done in conjunction with #3 to blend the responses together..... unless the drivers are chosen very very carefully to ensure the dont need any filtering to sum together just so.

 

 

58 minutes ago, RockRolley said:

unless someone can point me to an available solution.

There is none.   If you are designing your own speaker, then you will need to design this part too.

 

Unless you find someone elses build/design to copy (where they tell you what filters to use).

 

58 minutes ago, RockRolley said:

It seems that your sub woofers are passive rather than active? I've never used an active subwoofer, but understand that does away with the need for a crossover.

No, it just has a "crossover" built in, usually with adjustable frequency, slope, phase, etc.

[Warren Jones]

8 hours ago, RockRolley said:

Thanks for your input. It seems that people recommend a wide baffle in order to get sufficient bass out of the full range drivers, but you seem to have experienced a loss of imaging. To solve this, you've added woofers-is that right? As mentioned in my initial post, I get lost if I need to consider crossovers unless someone can point me to an available solution. It seems that your sub woofers are passive rather than active? I've never used an active subwoofer, but understand that does away with the need for a crossover. I'm open to adding woofers though for some reason reluctant to add powered subwoofer, but as mentioned also will get lost if I need to source a crossover for passive woofers without guidance. Do you have further recommendations regarding woofers? Thanks

 

Correct I added the woofers to solve the issue of lack of bass reduce baffle size. My subwoofers use a separate amplifier and crossover is a MiniDSP. There is a fair bit of measurement and tuning to get this working so if you decided to head down this route there would be a learning curve.

 

[Nada]

On 07/03/2022 at 2:44 PM, RockRolley said:

I’ve read good things ...

 

Id strongly suggest you get to listen to some "full range" speakers before you buy. 

 

Some love the micro dynamics and sound. Others don't.

[RockRolley]

On 08/03/2022 at 10:36 PM, Nada said:

 

Id strongly suggest you get to listen to some "full range" speakers before you buy. 

 

Some love the micro dynamics and sound. Others don't.

Thanks, I’ve got some Richard Allan 8inch full drivers. I enjoy some of their capabilities although plugging my 4 way transmission line speakers after them shows up deficiencies in some areas of the ‘full range’. Not surprising really… what they do well though has piqued my interest to see (hear) what well paired gear and well employed full ranges are capable of 

[Nada]

38 minutes ago, RockRolley said:

Thanks, I’ve got some Richard Allan 8inch full drivers. I enjoy some of their capabilities although plugging my 4 way transmission line speakers after them shows up deficiencies in some areas of the ‘full range’. Not surprising really… what they do well though has piqued my interest to see (hear) what well paired gear and well employed full ranges are capable of 

 

Nice. I can relate to your findings.  I really like the cross over free midrange of full range drivers.  Some of them could do with help from a bass woofer and tweeter   But seriously having a midrange that can look after 150Hz to 5kHz would solve heaps of challenges with mid-range crossovers. Have fun.

[RockRolley]

21 minutes ago, Nada said:

 

Nice. I can relate to your findings.  I really like the cross over free midrange of full range drivers.  Some of them could do with help from a bass woofer and tweeter   But seriously having a midrange that can look after 150Hz to 5kHz would solve heaps of challenges with mid-range crossovers. Have fun.

Yes, that seems to be the challenge: can I live without those high highs and low lows… but the midrange is so rewarding

[Nada]

On 13/03/2022 at 4:14 PM, RockRolley said:

Yes, that seems to be the challenge: can I live without those high highs and low lows… but the midrange is so rewarding

 30 mins away:

https://www.gumtree.com.au/s-ad/clyde/speakers/vintage-peak-coral-10cx50-full-range-speakers/1291491099

[xlr8or]

4 hours ago, Nada said:

 30 mins away:

https://www.gumtree.com.au/s-ad/clyde/speakers/vintage-peak-coral-10cx50-full-range-speakers/1291491099

 

http://glowinthedarkaudio.com/coral-10cx-50.html

[xlr8or]

These are also available:

 

https://www.ebay.com.au/itm/NEW-Pair-2-Zenith-49-1045-speakers-Wonderful-in-open-baffles-w-tube-amps-/125159788423

 

Further info can be found here:

 

http://glowinthedarkaudio.com/zenith-49-1045.html

[RockRolley]

On 16/03/2022 at 2:10 AM, xlr8or said:

 

http://glowinthedarkaudio.com/coral-10cx-50.html

Hey, thanks for your recommendations. I procrastinated and didn't get these, though I was tempted. There's a pair of 8CX available now that I'm considering. Any thoughts on the 8s?

[RockRolley]

On 08/03/2022 at 10:52 AM, davewantsmoore said:

 

A driver on an open baffle will not have a flat response.... what frequency the response is lacking will depend on the specifics (it will definitely lack bass, but could also be too low at higher frequencies too).

 

You have to do something to correct the response.   It could be:

 

1. Wide baffle

 

2. Driver with a peak in the frequency response due to the electro-mechanical system (eg. a "high Q" driver)

 

3.  A peak in the frequency response due to some sort of signal filter .... either a traditional "passive crossover"  (eg. a series indictor or similar, which pushes all the high frequencies down, thus increasing the lower frequencies relatively) ... or multiple sorts of "active" filters.

 

4.   Add more drivers to fill in the missing response.

 

Issues:

 

1.    Vibration.    Likely poor(er) direcitivty (which could sound like lack of clarity, or poor "image")

 

2.    The peak will be unlikely to be big enough or in the right place .... and the peak is often due to the bad performance of the driver motor (electro mechanical resonances)

 

3.   Is very powerful and flexible ... which means it can work well... but you can also make a very big and very wrong correction to the response and end up with "bad" sound.

 

4.   Needs to be done in conjunction with #3 to blend the responses together..... unless the drivers are chosen very very carefully to ensure the dont need any filtering to sum together just so.

 

 

There is none.   If you are designing your own speaker, then you will need to design this part too.

 

Unless you find someone elses build/design to copy (where they tell you what filters to use).

 

No, it just has a "crossover" built in, usually with adjustable frequency, slope, phase, etc.

Thanks for all of that feedback and apologies for the delayed response. It seems like you know your stuff. I, for some reason, am yet to get my head around making intelligent decisions to correct/plan for frequency responses etc. Perhaps what I need to do is identify a specific driver, describe the space I'll use it in and supply as much info as possible and just put it out there for the community to kindly offer recommendations for baffle size/design. As mentioned, I'll get lost if there is too much technical work to be done like crossover design and build. if I can get the best out of a full range driver by the baffle design and have a pair built out of beautiful looking materials, that would be heaven for me.  

[RockRolley]

On 08/03/2022 at 9:02 AM, Warren Jones said:

I've used Mark Audio Alpair 12P in an OB for many years with subwoofer. I can tell you from experience if you go too large with the baffle imaging suffers due to the vibrations off the baffle. A baffle can have as much or more radiating surface than the driver depending on how large it is. With this baffle approx 400x380mm the 12P XO to the woofers at 250Hz

 

This setup the 12P is magnet mounted and the baffle is covered with felt to reduce vibrations off the baffle, but it didn't stop it, removing the baffle improved imaging.

 

The woofer cabinet uses 2x 12" Visaton woofers.

 

Don't get me wrong even these sounded pretty good and better than the Linn speakers I had a few years ago. These have been replaced by a set of Linkwitz LXminis that blew them away.

 

Thanks and apologies for the delayed response. Are you saying do away with the baffle of the full range driver all together and build a bass box to handle the low frequencies? Although I'm keen to keep it simple and get the most out of just the single driver and baffle, I'm open to an additional bass driver. Thing is, I have no idea how to make or purchase an appropriate crossover to incorporate it. I must say, and I can't justify this, that I'm more inclined to want to incorporate a well selected bass driver with crossover than add a powered pre made sub. Maybe that's just a bit of old-school arrogance rather than clear thinking on my part...

[davewantsmoore]

7 hours ago, RockRolley said:

if I can get the best out of a full range driver by the baffle design and have a pair built out of beautiful looking materials, that would be heaven for me.  

It is possible.... but you will need to do one of two things, if you want to "design your own speaker".

 

Calculate / simulate what the result will be, before you do it.

OR

Just do "stuff", and measure the result.

 

Obviously, both of these techniques can compliment each other.

 

 

The other obvious option is to follow the detailed plans of someone else, plenty of other audio websites out there with people posting plans/build logs where the results are fairly well documents (not just subjective impressions).

[davewantsmoore]

7 hours ago, RockRolley said:

Thanks and apologies for the delayed response. Are you saying do away with the baffle of the full range driver all together and build a bass box to handle the low frequencies?

Yes you can do that, but then you need to make a "crossover" between the two drivers.

 

7 hours ago, RockRolley said:

a well selected bass driver with crossover than add a powered pre made sub. Maybe that's just a bit of old-school arrogance rather than clear thinking on my part...

 In a "powered pre made sub" they have selected the correct driver/box, and designed a (adjustable) crossover for you.    

 

[RockRolley]

16 minutes ago, davewantsmoore said:

In a "powered pre made sub" they have selected the correct driver/box, and designed a (adjustable) crossover for you.

Excellent point hahahah sounds like clear thinking hahah

I sometimes read people discussing using a powered sub with full ranges as either a short cut or even a sin  . Perhaps, given my uncertainty with crossovers etc. that is the smart move...

[RockRolley]

23 minutes ago, davewantsmoore said:

Calculate / simulate what the result will be, before you do it.

OR

Just do "stuff", and measure the result.

Can you advise with you would do and need to calculate/simulate?

I guess by 'do stuff', you mean play with different sized baffles/positioning/tilting etc. ?

I'd like to be more able and educated about it, I just don't know where to start. BTW thanks so much for your feedback

[xlr8or]

8 hours ago, RockRolley said:

Hey, thanks for your recommendations. I procrastinated and didn't get these, though I was tempted. There's a pair of 8CX available now that I'm considering. Any thoughts on the 8s?

 

It really depends on what budget you have in mind to spend and whether or not you wish to pursue trying other similar or even lower powered SET amps. The Glow in the Dark website I shared above is a fascinating read for open baffle speaker drivers, and the history of triodes that followed up to the release of the 300B. If I were to make a call on which single coaxial driver size would suit an open baffle design the best, it would be the 18" version from Lii Song F18:

 

AU $2,927.07 | Lii Song F18 18 inch home HIFI full frequency baffle speaker 1 pair
https://a.aliexpress.com/_mLtVFsi