High efficiency speakers appreciation and discussions

[mwhouston]

A thread dedicated to speakers having a rated efficiency of 96db\watt\meter or more.

 

Over the years I have built a number of speakers, mostly single driver, which have been high efficiency. We are all aware that low power valve and SS amps can struggle to produce good volume levels with speakers of efficiency lower then 90db. But team-up you flea power valve amp with a speaker featuring the Fostex FE206En and magic happens. Even SS amps in the 25W range can not always produce the dynamics which more powerful amps will produce into speakers with a more normal 87db rating. 

 

I have built four pairs of speakers three using the Fostex FE206En, the driver having a rating of 96db. From simple ported types to the super complex back loaded horn. See images. These have worked extremely well with 2 to 5W SE valve amps but some complain there is no weight behind the music. I think the counter argument to this is that these ultra light weight coned speakers produce better micro-dynamics, general dynamics and detail than there less efficient partners. Weight in notes can be enhanced with the use of active sub-woofers or assisted bass speakers and yet still retain the detail and dynamics of these special drivers.

 

Over the last three or four months I have been using only my DIY 98db efficient 12" Beyma concentric speakers (retro-thermionic - VoXConcentriC). My 5.8W DIY SE 300B plays to ear-bleeding levels when hook-up to the Beymas. They are Tannoy style and with a 2" Titanium tweeter produce reasonable bass to 50hz and bright treble response to 20K+. To pickup a little more weight in the lower register I team them up with 12" active stereo sub-woofers. This way I get bas down to 31hz, crisp micro-dynamics, detail and what appears to be unlimited head room. I have really fallen in love with these speakers. Even my 3W DIY 6V6 SE amp plays to excessive levels with these speakers. Voice, brass, and acoustic instruments sound excellent and alive through these inexpensive speakers. I like these Beymas so much I have ordered the 15" version.

 

Please post your experience, good or bad, with either commercially built or DIY high efficiency speakers. Any projects you may have in the future and would like to discuss here. Images are always good to. Even experiences at shows, demos etc.  

Edited October 31, 2015 by mwhouston

[darth vader]

I'd like to hear more of your thoughts on the Fostex FE206en speakers you made, I'm considering making a set. Interested in what you say about no weight behind the music from them, do you think this comes partly from driving them with low watt valve amps?

I'm considering them from an affordability point of view, and I'm wondering if they would respond just as well with a different driver and what it might take to tune them to a different driver (something like a seas, maybe?)

[mwhouston]

The Fostex are nice and cheap and a good way to get into high efficiency drivers. The drivers will definitely sound different when driven with different amps. My Fostex folded horns were driven by a powerfull SS amp at a Melbourne Audio Club meeting. In the large room they sounded excellent, loud and bass really lifted.

I think high efficiency speakers out perform lower drivers with greater detail and a more immediate sound. They bring the sound into the room instead of sitting back. What's right and what is wrong? The Beymas can be very left and right but produce excellent central image only when it is on the recording. They appear far more accurate with the imaging where other speakers I have always appear to plonk the sound in the middle with not a lot of width.

[mwhouston]

My main axe, my DIY 300B, decided to take a dive. The HT section of the power tranni shorted, taking out the fuse. I have contacted AVAT (who wound the tranni for me) to see if they can wind a new ranni on the iron of the old.

In the meantime I have brought out, once again, my DIY 6V6 amp, Black Lace. Though only 2 or 3W, the Beymas make it sound a lot more. The amp is strictly old school with 50+ year old all Ozzie tubes, carbon film resistors and NOS caps.

So far it sounds excellent. A really nice sounding amp and made even more enjoyable with the help of the Beymas.

[acg]

I am building something like this:

 

 

 

 

It is a duplication of a infamous Bostonians system which may end at seven channels if I keep my energy and build some mid-bass horns.  Those four channels shown are all around that 109dB sensitivity, then there will be some 8 driver bass arrays that will be about 100db sensitive.  The system will be fully active with line level crossovers and driven exclusively by SET amplifiers.  I've made a lot of the components and can't wait to start piecing it together and getting some sound.

[Sir Rab of Everest]

Where's the cat, Anthony?

[acg]

I'm more a dog person Richard, and then really just working dogs.  Lucky fellow, you have heard that particular feline system...

[mwhouston]

I am building something like this:

 

My Macondo 1.jpg

 

My Macondo 2.jpg

 

 

It is a duplication of a infamous Bostonians system which may end at seven channels if I keep my energy and build some mid-bass horns.  Those four channels shown are all around that 109dB sensitivity, then there will be some 8 driver bass arrays that will be about 100db sensitive.  The system will be fully active with line level crossovers and driven exclusively by SET amplifiers.  I've made a lot of the components and can't wait to start piecing it together and getting some sound.

Big project. Looks good and very efficient.

[THOMO]

I think many people chase excessive sensitivity and the higher the sensitivity the harder it is to get everything working seamlessly together.If not impossible.

 

I have owned and built plenty and never got any of them sounding quite right.By contrast you can buy something like the JBL Studio 590s for $3000 which has 93db sensitivity and is easy to drive and unlike the vast majority of sensitive speakers comes with a flat frequency response and excellent driver integration and phase response.

Another good one as the Audio Note AN /E.

 

You can have a lot of fun building high sensitivity speakers and I guess you have to just appreciate them for the things they do well.Do not expect perfection however.

[mwhouston]

I think many people chase excessive sensitivity and the higher the sensitivity the harder it is to get everything working seamlessly together.If not impossible.

 

I have owned and built plenty and never got any of them sounding quite right.By contrast you can buy something like the JBL Studio 590s for $3000 which has 93db sensitivity and is easy to drive and unlike the vast majority of sensitive speakers comes with a flat frequency response and excellent driver integration and phase response.

Another good one as the Audio Note AN /E.

 

You can have a lot of fun building high sensitivity speakers and I guess you have to just appreciate them for the things they do well.Do not expect perfection however.

In hifi there is no perfection. There is only the sound that makes you happy. Currently my Beyams are making me more than happy. And what is even better there are making my flea power SE maps sound extremely good. Ive just started an EL84 SE UL amp. Possibly only a few watts. BUT on the Beymas this little amp will sound like 100W. Now that's perfection.

[Happy]

Another SNAer told me the true Hi Fi starts from 95dB.

Sent from my iPad using Tapatalk

[Tasebass]

I am building something like this:

 

 

 

Are you a campanologist too  acg??

 

Hells bells when there finished......cant wait!!!

 

Tase.

[mwhouston]

Many years back I got into building chip amps. They produced about 40W, very low distortion and only required two resistors and two 1500uf electros, minimalist and good. Also I was into Foxtex FE206En drivers, so I have a low distortion 40W pc amps with 94db efficient speakers. I made comments on a forum that this combo was unnecessary that medium power amps didn't need high efficiency speakers.

One guy took me to task and said to even approximate the dynamics, volume and force of a live performance you require thousands of watts and extremely efficient speakers. I never forgot what he said though at the time I didn't agree but more likely could not understand what he was getting at. Now having the Beymas In place with 6W 300Bs and 2.5W 6V6 SE amps I'm starting to appreciate dynamics.

I have also run the Beymas with my 180W Tripath power amp with staggering results. Dynamics and detail overload. Even with my 6V6 SE flea power amp, (Black Lace), it has had me jump with live Classical performance in some dynamic parts. I'm now wondering if every low efficiency speaker is not really delivering and only high efficiency speakers are bringing us closer to a true live performance.

Edited November 5, 2015 by mwhouston

[jimcan]

Hi Mark,

 

I have found this speaker system sensitivity/efficiency thing to be a bit of a minefield.

 

A number of years ago, I got into Open Baffle speakers, specifically Hawthorne Audio Silver Iris's, which consist of a modified Eminence ( I think) 15" driver mated with a Radian compression tweeter and stitched together with a crossover network like this:

 

 

I was able to run this just fine with a 6CL6 SEP Spud amp with a massive 3 watts or so per channel, albeit with additional bass support.

 

A year or so ago I "upgraded", and replaced the compression driver with an AMT driver:

 

 

The crossover required to stitch this to the 15" woofer was designed by Danny Ritchie of GR Research and looks like this:

 

 

Much higher parts count obviously. I presumed it would all be a straightforward changeover for the better, but that was not the case.

When the anticipated higher quality sound did not emerge, there was much wailing and gnashing of teeth and WTF is going on here

 

In desperation, I tried a higher power solid state amp and was treated to a miraculous transformation. With much regret my Spud amp was mothballed

and one of Earles Topaz KT120's ordered, and is in use currently with no issues.

 

I guess I learnt that driver sensitivity on its own does not tell the whole story, the crossover has a bearing as well.

Still looking for something that the Spud would be happy with (Pauls HE2 perhaps?) so I can put it back in service sometimes, for a change.

 

Cheers,

Jim

[Guest]

That "no no" cat is @@davewantsmoore 's,  not Anthony's. 

 

The PSE144, is possibly one of the most efficient speakers coming in at (I think I remember correctly) over 105dB, 1w @ 1m

 

The other driver, the Acoustic Elegance TD18+4, is 98dB, 1w @ 1m. It has a magnet the size of a baby's head.

 

Recent acquisition, waiting to be picked up, Eminence Magnum, 95dB, 1w @ 1m. Measured in the enclosure

 

 

Now, there is another another system in the same room that would be lucky to get close to 88dB, so there is going to be a bit of fun actually answering all the many questions,  when both finally are commissioned sorry, set up, around Christmas      

 

Nothing like grabbing the "bull" by both horns and separating the facts from the myths in the real. Move on with the journey. Have deep respect for those that have experience and express it, learn from them.

 

Regards

 

Edit, the low effiency system is 5500w, the high, 1000w for obvious reasons

Edited November 5, 2015 by Guest

[Newman]

I still reckon there's more to it than "whatever makes you happy", by which standard every happy mp3-playing Beats wearer is an accomplished audiophile.

[mwhouston]

I still reckon there's more to it than "whatever makes you happy", by which standard every happy mp3-playing Beats wearer is an accomplished audiophile.

In his own mind, but not in mine.

[mwhouston]

That "no no" cat is @@davewantsmoore 's,  not Andrew's. 

 

The PSE144, is possibly one of the most efficient speakers coming in at (I think I remember correctly) over 105dB, 1w @ 1m

 

The other driver, the Acoustic Elegance TD18+4, is 98dB, 1w @ 1m. It has a magnet the size of a baby's head.

 

Recent acquisition, waiting to be picked up, Eminence Magnum, 95dB, 1w @ 1m. Measured in the enclosure

 

 

Now, there is another another system in the same room that would be lucky to get close to 88dB, so there is going to be a bit of fun actually answering all the many questions,  when both finally are commissioned sorry, set up, around Christmas      

 

Nothing like grabbing the "bull" by both horns and separating the facts from the myths in the real. Move on with the journey. Have deep respect for those that have experience and express it, learn from them.

 

Regards

 

Edit, the low effiency system is 5500w, the high, 1000w for obvious reasons

They are serious drivers. My 15" Beymas have left the US of A. They cost $2K landed, boxes $1K plus Xovers. It's an expensive exercise. If it fails I just blame me!

[mwhouston]

Hi Mark,

 

I have found this speaker system sensitivity/efficiency thing to be a bit of a minefield.

 

A number of years ago, I got into Open Baffle speakers, specifically Hawthorne Audio Silver Iris's, which consist of a modified Eminence ( I think) 15" driver mated with a Radian compression tweeter and stitched together with a crossover network like this:

 

 

I was able to run this just fine with a 6CL6 SEP Spud amp with a massive 3 watts or so per channel, albeit with additional bass support.

 

A year or so ago I "upgraded", and replaced the compression driver with an AMT driver:

 

 

The crossover required to stitch this to the 15" woofer was designed by Danny Ritchie of GR Research and looks like this:

 

 

Much higher parts count obviously. I presumed it would all be a straightforward changeover for the better, but that was not the case.

When the anticipated higher quality sound did not emerge, there was much wailing and gnashing of teeth and WTF is going on here

 

In desperation, I tried a higher power solid state amp and was treated to a miraculous transformation. With much regret my Spud amp was mothballed

and one of Earles Topaz KT120's ordered, and is in use currently with no issues.

 

I guess I learnt that driver sensitivity on its own does not tell the whole story, the crossover has a bearing as well.

Still looking for something that the Spud would be happy with (Pauls HE2 perhaps?) so I can put it back in service sometimes, for a change.

 

Cheers,

Jim

I dabbled with open baffle. Somethings I liked, some I didn't. Don't think I'll try it again soon. In the middle of a EL84 SE\UL amp.

[Guest]

Yea, the AE's were no picnic either from the US also, but the devil is in the detail as they say. 

Personally doubt you will be disappointed  have fun !

[Newman]

In hifi there is no perfection. There is only the sound that makes you happy. 

I still reckon there's more to it than "whatever makes you happy", by which standard every happy mp3-playing Beats wearer is an accomplished audiophile.

In his own mind, but not in mine.

 

Sure, but I could say the same thing about you. You don't care about true performance, you only care about being happy (in post #10). (just raising a point here, not insisting it is true of course)

[Newman]

Anyway, just to prove I'm not trolling, I have a history of being drawn to high-efficiency speakers. My current bass units are in a cabinet 6ft tall and that a hifi-listening guest once asked me why do I have a wardrobe in the room's corners. He wasn't kidding. 

Edited November 5, 2015 by Newman

[Happy]

I guess I learnt that driver sensitivity on its own does not tell the whole story, the crossover has a bearing as well.

Still looking for something that the Spud would be happy with (Pauls HE2 perhaps?) so I can put it back in service sometimes, for a change.

Cheers,

Jim

Passive XOs can eat up lots of power and sonics. Thats why I prefer active XOs or FR drivers.

Sent from my iPad using Tapatalk

[Happy]

Many years back I got into building chip amps. They produced about 40W, very low distortion and only required two resistors and two 1500uf electros, minimalist and good. Also I was into Foxtex FE206En drivers, so I have a low distortion 40W pc amps with 94db efficient speakers. I made comments on a forum that this combo was unnecessary that medium power amps didn't need high efficiency speakers.

One guy took me to task and said to even approximate the dynamics, volume and force of a live performance you require thousands of watts and extremely efficient speakers. I never forgot what he said though at the time I didn't agree but more likely could not understand what he was getting at. Now having the Beymas In place with 6W 300Bs and 2.5W 6V6 SE amps I'm starting to appreciate dynamics.

I have also run the Beymas with my 180W Tripath power amp with staggering results. Dynamics and detail overload. Even with my 6V6 SE flea power amp, (Black Lace), it has had me jump with live Classical performance in some dynamic parts. I'm now wondering if every low efficiency speaker is not really delivering and only high efficiency speakers are bringing us closer to a true live performance.

So you had better results with the 180w?

Sent from my iPad using Tapatalk

[Guest]

Interestingly, my experience was "more power the better" particularly noise floor and SQ, more life like and dynamic a performance. 

 

EDIT, prticularly at low volumes, may have something to do with the FET A/B Amps running biased hard on running class A 

Edited November 5, 2015 by Guest