My Open Baffle and OB history is as for now.
I started in 2015 a project with my now wife. She is good with tools and I stick with the computer, solderiron and the electroacoustics. We started with a Dayton AMT and 2x2 12” GPR drivers. The LF fitted our budget and the QTS/Fs was fine from a OB point but that was all about it.
We then got hand on 2x2 12” custom designed drivers and thay keep the wheel turning. We were happy with the result. The size and LF output was very good on our room. The sound reminded me of my dads ESS AMT-1b but with less hump in the low end.
Then we started to reseach different FR drivers. Cube Audio Fc 8 was the first - not impresive. We even builded the suggested cabinet and it was just not our cup of tea. Later we learned dane who owned SAL. He made a 5” driver and we tried that. A different and in our ears a better sounding driver but still not it. We felt we needed a bigger FR and learned Lii Audio from a more commercial point of view. First we had Fast 8. Compared to what the Dayton and SAL did they were just a budget driver and thequality was poor in comparison. Sounded like a Lowther on a grey rainy day screaming for attention. We parked the F8 for a while and started to source Alpha15a and later SD Audience. In the meantime we received a set Lii Audio F15 and a set of the newest Crystal 10 was on its way. With the Alpha 15 the Fast 8 didn’t improve. We parked them again and tried 1 Alpha 15 and F15. A good match but the F15 beams (by nature) and lack the highest frequencies. A dark sounding speaker.
The sysyem also had problems with low powered tube amps. By nature these don’t like speaker systems with a high emc. The Crystals arrived and had a short time in this configuration. Not much better than Fast 8 but 4 times more expensive. We had a couple of quality issues with F15 and the Crystal. Loose phaseplugs and surrounds not properly glued. On the Crystal 10’s app 20% of the cone has not contact with the foam surround - on both drivers. F15 has their logo not printed on the right spot so either the logo was out of center or the screws…..all drivers received from this company had dirty finger prints on the metal parts. Later Lii was suspected (again) for counterfeit and publishing specs that is not real when you meassure them. We got rid of our Lii Audio drivers and concluded that the expensive ones is a gamble and the cheap ones is - you get what you pay for and could for some diy’ers be a good entry driver but nothing more.
The next driver we received was from Ukraine - a 10”, alnico motor, phenol spider, leatherskin surround and mulberry paper. This was another ball game and the price was in the area of a Lii Audio Crystal 10. But the quality - here we could talk about forgetting the speaker. It was music right out of the box. We got more curious and concluded that the price level usd/euro 1000 is where the action begins and you get a substansial return of investement coverintg the many hours spend. We were also aware of that form time to time there will be new brands popping up or drivers available from bespoke makers like the 10” alnico we enjoyed for a bit less money - but the party starts around this pricelevel.
Next was to investigate the buzz about field coils. And after reading the info available here and elsewhere on the internet we then understood why the focus is low. We started to investigate the concept and it hsitory and it raised more questions than answers. We concluded that we needed to try a set. The choice were made for a set of EMS LB8EX - why? The price was fine and they managed to reply our inquiry. Some friends in Japan helped out with a low priced powersupply that, as they said, would make the drivers perform at a 90% level. We got the drivers. Open the card box and inside found a plywood box containing the two securely bolted to the bottom of the box. A good start for a set of drivers retaling Euro 1430 ex sales vat. But we could not conclude that they were better than the alnicos. They were both very good drivers. And even with different amplifiers and cables there was no winner.
So the big question was and still is….1) will the last 10% help in the psu? It will take a replacement of the smsp to a traditional psu. 2) Will a psu with adjustable voltage make a difference in OB - we settled for 12 volt/3a recommended by Michel Fertin. a) We dont need it to adjust QTS. b) we can l-pad to high efficiency if needed. c) yes a difference in magnet flux affect the typical shouting found in many FR drivers but this also relate to the whizzer design. The 10” alnico had a fine balance so it is possible to design whizzers that do the job.
We can not yet conclude if permanent magnets are better than field coils. Maybe we have missed something? In the beginning of 2022 we decided to relocate to Asia and unfortunattely we could not bring all our hifi with us. We found new homes for the drivers. The alnico drivers is not available as we write but they are on our short list. We are now starting on a fresh and with a blank sheet……EMS and Supravox is also on our list and we are open to suggestions but also to learn about which companies we should stay away from.
I started in 2015 a project with my now wife. She is good with tools and I stick with the computer, solderiron and the electroacoustics. We started with a Dayton AMT and 2x2 12” GPR drivers. The LF fitted our budget and the QTS/Fs was fine from a OB point but that was all about it.
We then got hand on 2x2 12” custom designed drivers and thay keep the wheel turning. We were happy with the result. The size and LF output was very good on our room. The sound reminded me of my dads ESS AMT-1b but with less hump in the low end.
Then we started to reseach different FR drivers. Cube Audio Fc 8 was the first - not impresive. We even builded the suggested cabinet and it was just not our cup of tea. Later we learned dane who owned SAL. He made a 5” driver and we tried that. A different and in our ears a better sounding driver but still not it. We felt we needed a bigger FR and learned Lii Audio from a more commercial point of view. First we had Fast 8. Compared to what the Dayton and SAL did they were just a budget driver and thequality was poor in comparison. Sounded like a Lowther on a grey rainy day screaming for attention. We parked the F8 for a while and started to source Alpha15a and later SD Audience. In the meantime we received a set Lii Audio F15 and a set of the newest Crystal 10 was on its way. With the Alpha 15 the Fast 8 didn’t improve. We parked them again and tried 1 Alpha 15 and F15. A good match but the F15 beams (by nature) and lack the highest frequencies. A dark sounding speaker.
The sysyem also had problems with low powered tube amps. By nature these don’t like speaker systems with a high emc. The Crystals arrived and had a short time in this configuration. Not much better than Fast 8 but 4 times more expensive. We had a couple of quality issues with F15 and the Crystal. Loose phaseplugs and surrounds not properly glued. On the Crystal 10’s app 20% of the cone has not contact with the foam surround - on both drivers. F15 has their logo not printed on the right spot so either the logo was out of center or the screws…..all drivers received from this company had dirty finger prints on the metal parts. Later Lii was suspected (again) for counterfeit and publishing specs that is not real when you meassure them. We got rid of our Lii Audio drivers and concluded that the expensive ones is a gamble and the cheap ones is - you get what you pay for and could for some diy’ers be a good entry driver but nothing more.
The next driver we received was from Ukraine - a 10”, alnico motor, phenol spider, leatherskin surround and mulberry paper. This was another ball game and the price was in the area of a Lii Audio Crystal 10. But the quality - here we could talk about forgetting the speaker. It was music right out of the box. We got more curious and concluded that the price level usd/euro 1000 is where the action begins and you get a substansial return of investement coverintg the many hours spend. We were also aware of that form time to time there will be new brands popping up or drivers available from bespoke makers like the 10” alnico we enjoyed for a bit less money - but the party starts around this pricelevel.
Next was to investigate the buzz about field coils. And after reading the info available here and elsewhere on the internet we then understood why the focus is low. We started to investigate the concept and it hsitory and it raised more questions than answers. We concluded that we needed to try a set. The choice were made for a set of EMS LB8EX - why? The price was fine and they managed to reply our inquiry. Some friends in Japan helped out with a low priced powersupply that, as they said, would make the drivers perform at a 90% level. We got the drivers. Open the card box and inside found a plywood box containing the two securely bolted to the bottom of the box. A good start for a set of drivers retaling Euro 1430 ex sales vat. But we could not conclude that they were better than the alnicos. They were both very good drivers. And even with different amplifiers and cables there was no winner.
So the big question was and still is….1) will the last 10% help in the psu? It will take a replacement of the smsp to a traditional psu. 2) Will a psu with adjustable voltage make a difference in OB - we settled for 12 volt/3a recommended by Michel Fertin. a) We dont need it to adjust QTS. b) we can l-pad to high efficiency if needed. c) yes a difference in magnet flux affect the typical shouting found in many FR drivers but this also relate to the whizzer design. The 10” alnico had a fine balance so it is possible to design whizzers that do the job.
We can not yet conclude if permanent magnets are better than field coils. Maybe we have missed something? In the beginning of 2022 we decided to relocate to Asia and unfortunattely we could not bring all our hifi with us. We found new homes for the drivers. The alnico drivers is not available as we write but they are on our short list. We are now starting on a fresh and with a blank sheet……EMS and Supravox is also on our list and we are open to suggestions but also to learn about which companies we should stay away from.
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@Wow Factor have you looked at Lowther Loudspeaker PM6A 15 Ohm Silver voice coil?
https://assets-global.website-files.com/60642ec35aaa96e4388753a3/61430eb78ed96a08cf0dc8cb_PM6A.pdf
https://assets-global.website-files.com/60642ec35aaa96e4388753a3/61430eb78ed96a08cf0dc8cb_PM6A.pdf
Yep but I am affraid of that they will need a supporting tweeter for our purpose.
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Yeah, whereas my PM6A 15ohm Al coil easily notched flat at 7500hz. Bass OK too in a small TLonken. But still sounded powder dry.
You could also, next to the ususal suspects look at Sonido. They make great drivers, very lowther like but better made and they are also not overpriced. Something like the SFR-200A may fit your need.
http://www.sonido.hu/termekek.php?lang=en
http://www.sonido.hu/termekek.php?lang=en
I own the lb12 evo, much bigger motor and skinny frame compare to mk2, can't compare sound wise as I never owned the mk2, but the evo seems to be made for OB as it's the way Fertin use's it for demo...
My own personal thoughts are you should try drivers in a completely different size. I find 4 inch is as big as it goes if you really wanted good details. So I will suggest Faitalpro 3Fe22 and Fatailpro 4Fe32. Needs a big inductor and parallel resistor to get it to be flat...
Of course I mean it in the context of having a 15" OB to do bass work...
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Been there. It was the first size I tried after the Dayton AMT. I bettered the sound but I still feel the size of get smaller. The best (subjective) drivers I have tried is 8”-10” but I am facinated by the sound of some bigger versions to assisted by a tweeter depending on the brand - my road looks o have no end yet but what the heck - that is a part of the “infection” 😎
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So... out of curiosity what was it that you didn't like about smaller drivers... the smaller imaging? lack of presence?
Oon
Downsizing and make things smaller than real. Feel that there is something missing in the crossover area between a 15” and a 5-6”.
Yes so. This was one of my goals and in addition direct contact with customers, so that it was possible , for example, to satisfy individual requests.
/Istvan.
/Istvan.
