Researching the best high-sensitivity 8" driver for OB ~

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-Richard-

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I am resuming my research for an 8" high-efficiency driver for use in my Open Baffle speakers. As close to 99db sensitive as possible.

I am currently enjoying my Open Baffle speakers using the latest iteration of the small TBI amplifier (version 3) with the 8" Dayton Neo drivers. I am using my new iPad Mini hooked up to the TBI (class D) and a few easy to use apps... such as Pandora. Even in Pandora's lowest resolution mode the sound it quite beautiful... especially on small scale string classical music, like violins, violas and cellos. Who knew that an iPad Mini could bring such musical bliss into our lives... a lovely revelation!! 

For fun, I want to re-enter the flea-watt world of Single Ended Triode amplification... perhaps using the 45 tube (2 or less watts) or the 2A3 tube (3 to 4 watts). I am thinking of the Bottlehead Stereomoure kit.

I want to use a pair of full-range (wide range) drivers that are close to 99 db sensitive.

So far, according to what I have read, this 'breed' of driver tends to have a rise in the upper frequencies sometimes causing a 'shout', and in many, if not all cases, they need to be augmented to shelve down this tendency (whether passively or actively).

Here is my question: Has anyone in our community read about or experienced a close to 99db sensitive 8" driver that does not have this 'shouty' characteristic... like Lowther's for example are reputed to have? And therefor sounds nicely resolved in the higher frequencies so that it did/does not need any form of alteration (sounds perfect as it is)?

Thanking everyone in advance for your kind help.

With Warmest Regards ~ Richard (ready-for-another-excursion-into-the-magic-world-of-Open-Baffle-speakers-using-2-watts)

MJK

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #1 on: 12 Aug 2013, 06:11 pm »
Richard,

I have used Lowther drivers for over 10 years, several times in OB applications. In my Lowther OB systems, shout has never been an issue.

http://www.quarter-wave.com/Project10/Project10.html

Martin

Ric Schultz

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #2 on: 13 Aug 2013, 02:45 am »
You did say best, not cheapest best.  So, that means you probably want the best Voxativ.  Check them out on the Solen site.  Be prepared to spend 9-15K for a pair.  The best ones are over 100db sensitivity.  Nothing but raves about these speakers.  http://solen.ca/pub/index.php?catalogue=show&niveau1=&niveau2=&niveau3=&niveau4=&origmanuf=%2Fpub%2Findex.php%3Fcatalog%3Dmanufacturers%26s1%3D14%26show%3Dl&s1=2&man=53

JohnR

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #3 on: 13 Aug 2013, 07:46 am »
One of those (field coil) drivers said "up to 108".

That's amazing (if true).

matevana

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #4 on: 13 Aug 2013, 02:17 pm »
I realize this is a bit off topic and isn't meant to be a direct response to your question but thought you might like to consider nonetheless. I have been experimenting with a really neat 8" high efficiency extended range driver that I run in tandem with a small neo tweeter from a 3 watt tube amp. I have measured a conservative 97 dB 1w/1m from this driver. There are three interesting aspects to this driver:

1) It is a hemp cone driver intended for guitar applications yet has a respectably flat response and maintains close to 97 dB over it's intended range w/1 watt.
2) The driver's Qts is .88 and performs nicely in open back; with it's hemp construction it sounds warm and clear with very fluid mids. I believe the former is paper which contributes to its pleasant sound.
3)  The retail price is $69 US

The driver is an Eminence 820H and is a relatively new product. It has a 4 ohm nominal impedance but I am able to drive them w/o issue from my small SET amp. This driver crossed at around 2.2k to a small efficient dome produces none of the characteristic shout you are looking to avoid.

-Richard-

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #5 on: 13 Aug 2013, 06:39 pm »
Hi Martin ~ I am very excited to hear that your excursions into OB designs using Lowthers did not find them 'shouty' in the upper frequencies. I have always been very curious about Lowthers and many really extraordinary speaker designers have taken a whirl with them with some form of 'horn' design, like Rethm (very expensive, terrific design) used to do. Reviewers (strange breed that they are) were not always unanimous about the 'success' of horn designs using Lowthers... but who knows what they were/are listening for (?)

I am very attracted to the Lowther Alnico versions... of course they are not cheap. They have 2 versions of their own OB designs: http://www.lowther-america.com/OpenBaffleSpeakers.html

A quote from their website concerning the smaller of their 2 OB versions: "I call it TOA (Tiny Open baffle Alnico). It utilizes the PM6A and a Tone Tubby Alnico 12" woofer with a series crossover at 200 hz. Both drivers were 15 ohms, and 96 dB/watt efficient. The lows extend to about 65 hz, and a sub-woofer fills in below that." And their larger version: "This started with the PM5A Lowther, and the Great Plains Audio reproduction of the Altec 416A for bass."

I looked at your OB designs using Lowthers: http://www.quarter-wave.com/Project10/Project10.html  I strongly recommend everyone in our OB community read Martins excellent and beautifully written overview of his journey into the magic of OB's using Lowthers. Martin's extremely honest rendering of his experience is particularly refreshing. I notice that the dBx Driverack PA has been 'updated' to a plus (+) now and the description sheet talks a lot about 'automatic' this and that... I hope this does not mean that some of the manual control has been compromised from this interesting active crossover product: price around $500.

Hi Ric ~ Yes... I have looked into the Voxative drivers. Srajan has spilled quite a lot of digital ink on their Ampeggio folded horn design: http://www.6moons.com/audioreviews/voxativ/voxativ.html

He has written about them in several other articles as well. I have been in touch with their fascinating designer, Ines Adler, a women who has already created a powerful stir in what is ostensibly a 'mans' world. She recommend to me using the AC 1.5 driver for OB application. They are about $2700 with shipping from Germany. There is an American company here in CA that is supposed to sell Voxative drivers and complete speakers... they never return my phone calls or emails. The Voxative website states that the AC 1.5 uses a "less expensive ferrite magnet". They are gorgeous of course. Some chat room DIY'ers doubt the too-good-to-be-true smooth frequency response chart that Voxative publishes about them.

Srajan feels that the Ampeggio sound is a bit 'lean'. It is not entirely clear what this means... especially since Srajan is now off SET tube designs (on again, off again, drives sales and our constant need to refresh and stimulate) and is using among others, Nelson Pass's transistor amplifiers (Nelson is a great contributor to the DIY community and his new low watt amps are highly eulogized). It could be that Voxative's interest in very high sensitivity drivers (which I adore) means a leaner-than-usual presentation overall. How this compares to Lowther's presentation is not clear to me yet.

The AC 1.5 is a seductive design. However Lowthers do enjoy a well-earned through-many-years reputation. The Voxative AC 1.5 would have to be purchased on 'faith'. At near $3000 I don't know if I have that much 'faith'. So far I don't seem to.

Hi JohnR ~ I have struggled (at least inwardly) with the idea of using field-coil drivers. Anyone interested in an all-out pushed-to-the-logical-conclusion/solution masterly high-performance OB design cannot ignore the fact that field-coils are probably the best full-range driver that is possible to use. However, I don't like the 'fussy' nature of having to use batteries with their constant need to re-charge, or voltage regulation, which many aficionados of field-coil drivers feel is sub-standard, performance wise.

I am looking for as-simple-as-possible 'solution', even if it means not approaching the highest possible musical magic possible. Besides... I feel confident that using field coils will mean upgrading everything else I use in the audio food-chain and I am not quite ready for that kind of commitment... and my budget will not allow too many expenditures beyond splurging on boutique drivers.

Hi Matevana ~ Your very interesting post is not off-topic at all. It is right-on-target! I will look into the Eminence 820H drivers as soon as possible.

Thanks everyone... and I really mean it... for your wonderful feedback and suggestions. I need to study this a little bit more and I will certainly keep in touch... especially once I set up a new higher db sensitivity 8" driver and using a flea-watt amp.

If anyone has any more suggestions I am extremely interested to hear them... thanks in advance!!! Have a lovely day.

With Warmest Regards ~ Richard
« Last Edit: 14 Aug 2013, 02:35 am by -Richard- »

versus rider

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #6 on: 19 Aug 2013, 11:37 am »
One of those (field coil) drivers said "up to 108".

That's amazing (if true).
I have heard the voxativ field coil in their own Ampeggio due bacl loaded horn and its absolutely amazing for a single driver, excellent bass too. I had to have a serious talk with myself about not  buying them as they sound as good as my open baffle bass/tractrix horn/ Raal tweeter set up developed over several years. At £6k a pair they are not cheap but if I went back to single driver they would be first choice. They sound even better with a battery supply in place of the power supplies from voxativ.

rjbond3rd

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #7 on: 19 Aug 2013, 01:45 pm »
The best large fullrangers I've heard were the Feastrex D9NF and the Lowther field-coil.  Both sounded better than the Feastrex field coil (so field coils don't have any automatic advantage).  I have AER's and I thought the Voxativ sounded exactly the same in the midrange and treble (to my ears, anyway).

The Lowther "shout" turns out to be people putting the drivers in the wrong enclosures (bad design) or sometimes also people listening (or measuring) too close and on-axis, vs. a normal listening position.  They are worth the patience to do right (although personally, I think my 12x12 room was also too small for them).

-Richard-

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #8 on: 21 Aug 2013, 05:15 pm »
Hi versus rider ~ 6,000 pounds (where is the pound sign on my Apple keyboard?) for the voxative field coil drivers seems a bit low to me. Their American dealer has the Voxative field coil AC-X2 listed as $16,875 a pair... and their "ultimate" version lists for $37,800 a pair. Factor in the ancillary/supporting gear, including some form of baffle structure and the question arises: should listening to music be that expensive?

Money, of course, in and by itself has no meaning. It is just numbers. However, to accumulate large numbers (lots of 'money') usually requires an extraordinary effort of some kind, and even if one just steals it, there is stress and risk involved. Just to cover the field there is also inherited "money" and winning the lottery.

But look how far we have journeyed away from the essence of what music actually means to us. Originally music was shamanic... it provided an entry point to inter-dimensional 'travel' within (drumming and rhythmic singing)... it also created a group experience of shared love, shared togetherness by providing a vehicle for mingling our tribal voices (listen to the a capella group singing of the Bush peoples of Africa)... it was also used to release the burdens of any activity like planting, and harvesting... and of course it could lift the spirit to unimaginable heights of transcendent flights of feelings. There is also the role music plays in dance, infusing movement with powerful drive.

If we do not sing or play a musical instrument ourselves, then we must rely on others to play or sing for us. And if we love to listen to recorded music, as Deborah and I do, then some form of playback is needed and that means technology. But must we spend thousands and thousands of dollars (those large numbers) to experience the essence of what music, and only music can do to release the spirit, like a trapped bird, from its cage?

That is where the DIY Open Baffle paradigm can be of enormous help to getting us closer to the magic of what technology can do to recreate the life in recorded music, at least so far at this time.

So the question for me is: Is it worth the leap in cost of the diminishing returns one hears as we attempt to get a 'little more' of this or that quality from ones OB drivers? More transparency, or detail, or resolution, or extension and so on. Put another way, is there a threshold where one hears something so qualitatively different from a more costly version of a driver, that it makes it impossible to live with the less expensive driver once this very costly driver is heard?

The strange part of this is that even if the pricier driver does do that for us, one gets used to the 'shock of the new' very quickly, causing an increasing and continuous demand for ever more 'shocking' new experiences. This really has nothing to do with the music itself. It is much closer to an auditory addiction. I have heard music played through terrible audio equipment and poor little radios, that lifted me to those transcendent heights. The suggestion here is that it is all about 'perception'... it points back to the perceiver, the perceiving mind, and not necessarily to the source.

So, can we find a driver, for example an 8" wide-range driver, that can take us close, say to 70%, of the magic of what a very costly driver can do in the OB paradigm?

Here is another place where I think the OB paradigm works for us yet again. It allows drivers to breath... to 'live' in their natural functioning fluid state without imprisoning it in a box. This goes a long way to releasing the music so it can 'live'.

Hi rjbond3rd ~ Thank you for sharing your insights concerning the Lowther 'shout'... which as you have pointed out, could be the result of poor implementation. Your reference to 'normal' listening position is of course just a conditioned idea... I am not saying that it is not a reasonable assumption... normal distances in our 'living' or 'listening' rooms reflects the way one usually arranges furniture (the male usually defers to the wife or significant other to make this decision). But perhaps you are right after all, if one considers that drivers may be designed, whether through tradition or inherent limitations, to be listened to from certain preconceived distances.

I would love to purchase a pair of Lowthers from the A series. But I hesitate thinking that they may not deliver the promise of being exponentially 'better' than a much less expensive driver of a similar design.

------------

Just thinking out loud here.

Thanks for sharing your thoughts, suggestions and insights.

With Warmest Regards ~ Richard

rjbond3rd

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #9 on: 21 Aug 2013, 06:47 pm »
Quote
So, can we find a driver, for example an 8" wide-range driver, that can take us close, say to 70%, of the magic of what a very costly driver can do in the OB paradigm?

I think one such driver would be the $50 FE103En but there are others.  Good things happen when the driver's diameter scales down.  What you lose in bass is made up in the treble.

But having said that, the Lowther 6" drivers like the A45 are not too expensive ($1400 I think).  And both the 6" and 8" make -incredible- midranges.  The very best OB I ever heard was at an RMAF several years ago, and it was the Lowther field-coil 8" with RAAL tweeter and a servo woofer (of some kind).  These drivers were mounted on simple rectangular slabs, but the sound was miraculous.

You could often hear sounds "behind" you, and the imaging / soundstage was (no exaggeration) holographic (whether that was in the recording or not, it was 3D).  But obviously tons of effort and expertise went into making that system sound so great.

guest60106

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #10 on: 3 Sep 2013, 12:46 am »
I realize this is a bit off topic and isn't meant to be a direct response to your question but thought you might like to consider nonetheless. I have been experimenting with a really neat 8" high efficiency extended range driver that I run in tandem with a small neo tweeter from a 3 watt tube amp. I have measured a conservative 97 dB 1w/1m from this driver. There are three interesting aspects to this driver:

1) It is a hemp cone driver intended for guitar applications yet has a respectably flat response and maintains close to 97 dB over it's intended range w/1 watt.
2) The driver's Qts is .88 and performs nicely in open back; with it's hemp construction it sounds warm and clear with very fluid mids. I believe the former is paper which contributes to its pleasant sound.
3)  The retail price is $69 US

The driver is an Eminence 820H and is a relatively new product. It has a 4 ohm nominal impedance but I am able to drive them w/o issue from my small SET amp. This driver crossed at around 2.2k to a small efficient dome produces none of the characteristic shout you are looking to avoid.


That looks like a very interesting driver indeed for OB mat.

-Richard-

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #11 on: 3 Sep 2013, 05:34 am »
Hi Harvey and Matevana ~ Reading what little there is about the new Eminance 820H suggests they could sound quite nice up to 2kHz, after that the frequency chart has them going on a roller coaster. The hemp material could help to smooth out the mid-range and perhaps warm it up as well, as Matevana suggests... meaning less dry, less analytical, perhaps less hi-fi sounding. Although, admittedly, that is an area known to be very subjective.

The question then is what tweeter will work with it from 2kHz upwards?

Tweeters definitely serve an important purpose in 3-way closed-baffle designs... and if they go low enough, some AC members report they could be used in a 2-way design as well... meeting the 'bass' driver somewhere in the middle.

I admit I have a very friendly bias toward 'single' driver coherent 'point-source' sound, it is very organic sounding. Even though within the OB paradigm a bass driver is usually called for, the crossover is usually so low, say from 60Hz to around 250Hz, we can consider the bass driver is actually 'filling-in' for the loss of lower frequencies which is the bain of OB physics... cancellation of lower frequencies due to their slower travel-time by the back wave. So in a practical sense the bass driver is not really working against the integrity of the 'single-driver' concept.

Once a tweeter is used, there are necessarily complications... synergy with the 'mid-driver', sensitivity issues, the amplifier has more now to 'get through'... to amplify, possible phase issues and so on.

So I would like to ask Harvey and Matevana and of course open it up to our community:

What tweeter would you recommend from 2kHz upwards that you might think compatible with the Eminence 820H?

Incidentally, the spec charts suggest a sensitivity closer to 96db for the Eminence 820H... still quite nice... especially for those of us using low powered amps. Like my current Millenia TBI version 3, class D amp. It sounds remarkably like a well-designed 45 SET amplifier... without the shockingly expensive tube set. I am looking at the new, just released, iFi iTube, that might just have a lovely synergy with it. Anyone looking for a preamplifier with the option to increase gain and that is using a NOS tube should look into it. At $300 it may be a game changer for people like me whose budget must squeeze value whenever and wherever it can. I am seriously considering ordering one.

With Warmest Regards ~ Richard 

matevana

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #12 on: 3 Sep 2013, 05:15 pm »
Well I haven't had much luck with any of the high sensitivity compression driver/horn combos, although others have. Just not my cup of tea I guess. I would say if that interested you though, you may want to look at some of the polyimide or mylar diaphragm drivers as opposed to titanium. Just seems to be a bit smoother for hi-fi.

While you may lose a bit of potential system efficiency by matching to a good quality dome, I would still go that route. My personal favorites are the Usher 9950, the Vifa XT19 dual radiator, the Dayton RS-28F silk dome and the Seas 27TBCD/GB-DXT.  The DXT and the XT19 are very well suited off axis. But I'm partial to the Usher overall. It's just a very pleasing tweeter to listen to and will do well crossed at 2k. It is known to be very "fast" for a dome, and can easily keep-up with dipole bass. While all of these can be crossed fairly low under normal SPL's, the Dayton will cross even lower and sound similar to the Usher (it's OEM'd by the same).

You could also explore crossing the Eminence 820H even lower, to a wide range driver like the Scan-Speak Discovery 10F/4424G00. You may lose a hair at the highest spectrum, but the driver is ruler flat over several octaves and your system will be dipole all the way up! It has a 90 dB efficiency rating which is impressive for a driver of it's kind. If you went this route, I would cross around 1k and improve upon any beaming artifacts. Also both drivers would be operating well into their comfort zone. 

versus rider

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #13 on: 3 Sep 2013, 05:37 pm »
Hi Richard, the original AC-X is about £6K, innes, the owner of voxativ had decided to replace them with the AC-X2 at £10K a pair, but during a recent visit to the UK she took advice from the UK agent to keep selling the AC-X and yes the permadour version are £23K. Haven't heard those yet. As I said they are almost as good as my three way, my three way having the edge in the bass which is to be expected with 15" drivers moving more air than an 8". If I ever decided to go back to single driver then the field coils would be the thing. At this time, due to me building new open back boxes for the woofers I am listening to 30 year old Wharfedale Lazer 60 two way standmounts with a 300B amp and valve cd player and its not bad, its also not a patch on my horn set up but if I had no choice I could be content. 
Hi versus rider ~ 6,000 pounds (where is the pound sign on my Apple keyboard?) for the voxative field coil drivers seems a bit low to me. Their American dealer has the Voxative field coil AC-X2 listed as $16,875 a pair... and their "ultimate" version lists for $37,800 a pair. Factor in the ancillary/supporting gear, including some form of baffle structure and the question arises: should listening to music be that expensive?

Money, of course, in and by itself has no meaning. It is just numbers. However, to accumulate large numbers (lots of 'money') usually requires an extraordinary effort of some kind, and even if one just steals it, there is stress and risk involved. Just to cover the field there is also inherited "money" and winning the lottery.

But look how far we have journeyed away from the essence of what music actually means to us. Originally music was shamanic... it provided an entry point to inter-dimensional 'travel' within (drumming and rhythmic singing)... it also created a group experience of shared love, shared togetherness by providing a vehicle for mingling our tribal voices (listen to the a capella group singing of the Bush peoples of Africa)... it was also used to release the burdens of any activity like planting, and harvesting... and of course it could lift the spirit to unimaginable heights of transcendent flights of feelings. There is also the role music plays in dance, infusing movement with powerful drive.

If we do not sing or play a musical instrument ourselves, then we must rely on others to play or sing for us. And if we love to listen to recorded music, as Deborah and I do, then some form of playback is needed and that means technology. But must we spend thousands and thousands of dollars (those large numbers) to experience the essence of what music, and only music can do to release the spirit, like a trapped bird, from its cage?

That is where the DIY Open Baffle paradigm can be of enormous help to getting us closer to the magic of what technology can do to recreate the life in recorded music, at least so far at this time.

So the question for me is: Is it worth the leap in cost of the diminishing returns one hears as we attempt to get a 'little more' of this or that quality from ones OB drivers? More transparency, or detail, or resolution, or extension and so on. Put another way, is there a threshold where one hears something so qualitatively different from a more costly version of a driver, that it makes it impossible to live with the less expensive driver once this very costly driver is heard?

The strange part of this is that even if the pricier driver does do that for us, one gets used to the 'shock of the new' very quickly, causing an increasing and continuous demand for ever more 'shocking' new experiences. This really has nothing to do with the music itself. It is much closer to an auditory addiction. I have heard music played through terrible audio equipment and poor little radios, that lifted me to those transcendent heights. The suggestion here is that it is all about 'perception'... it points back to the perceiver, the perceiving mind, and not necessarily to the source.

So, can we find a driver, for example an 8" wide-range driver, that can take us close, say to 70%, of the magic of what a very costly driver can do in the OB paradigm?

Here is another place where I think the OB paradigm works for us yet again. It allows drivers to breath... to 'live' in their natural functioning fluid state without imprisoning it in a box. This goes a long way to releasing the music so it can 'live'.

Hi rjbond3rd ~ Thank you for sharing your insights concerning the Lowther 'shout'... which as you have pointed out, could be the result of poor implementation. Your reference to 'normal' listening position is of course just a conditioned idea... I am not saying that it is not a reasonable assumption... normal distances in our 'living' or 'listening' rooms reflects the way one usually arranges furniture (the male usually defers to the wife or significant other to make this decision). But perhaps you are right after all, if one considers that drivers may be designed, whether through tradition or inherent limitations, to be listened to from certain preconceived distances.

I would love to purchase a pair of Lowthers from the A series. But I hesitate thinking that they may not deliver the promise of being exponentially 'better' than a much less expensive driver of a similar design.

------------

Just thinking out loud here.

Thanks for sharing your thoughts, suggestions and insights.

With Warmest Regards ~ Richard

-Richard-

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  • Posts: 853
Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #14 on: 4 Sep 2013, 02:46 am »
Hi matevana ~ I don't know what you mean by "You could also explore crossing the Eminence 820H even lower, to a wide range driver like the Scan-Speak Discovery 10F/4424G00." I looked at the frequency chart for the Discovery and a severe break-up begins soon after 1000 Hz. I am currently using a 15" Eminence Alpha 15A crossed over to a Dayton Neo 8" wide-range driver. It is not clear what you have in mind for the Discovery? At less than 90db sensitivity I would not think that it would be a good match for 820H.

I appreciate your overview of several tweeters you have played with... thanks very much... a nice reference to have for those tweeters.

I suspect unless a tweeter is incredibly sophisticated/refined it will spotlight the upper frequencies in some way... that would not work for me. "More" is not my cup of tea... "natural" is where I live, musically. Deborah and I listen to live unamplified music and that is our reference for classical and jazz. We also love blues and many other genres that use amplified sound, but both of us cringe when the upper frequencies are overly exaggerated.

Hi versus rider ~ The British pound has long since de-coupled from the US dollar, thanks to a long standing policy by the US to ramp-up our money supply as a way for the US to pay back our creditors with cheaper dollars. The British pound is now 1 to the US dollar's 1.55. So £6K's, which looks almost acceptable (for some with deep pockets) = $9,300.!!!! Apply that relationship (1 = 1.5) to the even higher numbers and you could experience a nose bleed for Voxative's premium field coil versions.

If I can get somewhat close to what a field-coil can sound like, without the fuss of needing batteries to regulate the DC voltage supply, I would be quite happy. The music and the OB paradigm can do the rest to sprout wings on the soul.

Thanks for your insights about the Votative drivers. Over the last few days I have been eyeing the Voxative 1.5 with its 99db sensitivity and surprisingly flat extension (if one can believe their frequency charts) and thinking this could be the last driver I would ever need. Then I could even exercise my desire for another stab at a 45 SET amplifier (2 watts), like a Bottlehead kit.

With Warmest Regards ~ Richard

matevana

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #15 on: 4 Sep 2013, 03:18 am »
I see only about a 3 dB ripple in the 1k to 10k range for the discovery 10f. That's pretty flat by any standard. It's also supprisingly efficient.

The usher 9950 is a very realistic sounding soft dome. It is never harsh. If you poll those who have actually used this driver, the feedback is overwhelmingly positive. I listen mostly to acoustic jazz and it remains my go-to tweeter for the genre.

-Richard-

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #16 on: 4 Sep 2013, 05:03 pm »
Hi Matevana ~ I was looking at this chart from Madisound, for the Scanspeak Discovery 10F:


Thanks again for pointing out these drivers as possible solutions.

Warmest Regards ~ Richard

matevana

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #17 on: 4 Sep 2013, 06:12 pm »
Zaph's testing shows basically a flat line well over six octaves! You're not likely to find that with any dome. The ability to cross to the Eminence lower than intended is also a plus. The peak around 10k is easily dealt with but I would listen to it first. I'm just saying that it would make an interesting option.




Poultrygeist

Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #18 on: 5 Sep 2013, 12:02 am »
Hi Richard,

I have had good luck with the Realistic 40-1310A super horn tweeters. After trying a number of others including Vifa domes and Neo 3's they were the best match for my Eminence Beta 12LTA's.

The Japanese made Realistic 40-1310A is not the same as the Radio Shack 40-1310B ( Korea ) and 40-1310C ( China ) and looks to be the clone of a more expensive Fostex horn tweeter. I don't know it's sensitivity rating but it keeps up with the 97-98 db Betas. I use a single .47uf cap to tone down the sizzle.

I know I sound like a broken record but the Beta 12LTA goes to another level when you cut out the dust cap and add a phase plug. It's proven as enjoyable and more fun than the Tang Band W8-1808's.


-Richard-

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Re: Researching the best high-sensitivity 8" driver for OB ~
« Reply #19 on: 7 Sep 2013, 06:17 am »
Hi Poultrygeist ~ I googled the Realistic 40-1310A super horn tweeters and notice that they are no longer made, for sale only on ebay... and the price varies quite a bit. I wonder how you came to use them, or rather how you came to know about them at all?

I have never read anything you have written before this current post about the Beta 12LTA... or about your suggestion to "cut the dust cap and add a phase plug". They are sensitive at 97db... quite nice!! "...more enjoyable and more fun than the Tang Band W8-1808"? Really? That is quite a recommendation given the raves about the Tang Band in OB application!!!

I haven't seen a frequency chart for it yet... there are 15 reviews for it on Parts Express, most of them are from guitarists using it as a guitar speaker, one person for stage sound.

Where did you get the phase plug, from planet 10? or did you make your own? I must still have the pair of phase plugs Dave made for me from Planet 10 for my pair of Visaton B200 drivers.

I have been having an itch to try the B200's again in my simple flat OB's. Now that I have been listening to the Dayton Neo's for several months I am curious what the B200's actually sound like with my present set up: iPad mini connected to the TBI version 3. Simple. The amazing thing is how very good the Daytons sound without a DAC, when the music I stream from Internet radio stations on the iPad mini stations is broadcast in a hi-res format. Quite startlingly good.

The suggestion here is that you could buy incredibly expensive appliances, like DAC's (I am not using one yet) but when the streaming music is of a hi-rez quality, the sound in OB is sensational. And all of this on-the-cheap!

Can it sound better? Yes... there is enormous room for hi-end appliances to bring out the qualities that we love (if not actually crave) in our home music experiences. But at a cost that for me does not seem attractive. I am not in love with appliances anymore... although I do love well designed audio products. And given an open-ended budget, who wouldn't want to have pricey beautifully designed audio products pulling out the last drop of magic from ones beloved music?

I find your suggestion of the Beta 12LTA quite intriguing, Poutrygeist!!! and at $80 each, if they are as good as you suggest, it would be a steal!!! This may be just what I am looking for... a gem of a driver hiding in the shadows because they do not have the pedigree or 'branding' that the expensive products enjoy.

I still favor a full or wide-range driver that does not need a tweeter... with a well-designed Alnico magnet... I am certain they can bring that smoothness (if not actual warmth) they are known for to the all-over musical presentation.

Thanks for the very positive suggestion.

With Warmest Regards ~ Richard