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Offline Clark B.

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Reply #495 on: November 16, 2013, 12:27:38 PM
I realize I didn't post about why I was talking about Feastrexes and Subs yesterday. 

Over the years, I've fielded many questions about the 5" feastrex drivers and how well they would mate with subs. 

For instance, would the Dungeness do well if mated with the Feastrexes? 

It wouldn't be necessary as the Dungeness only has frequency overlap with the 5" Feastrexes in the Uni cabinets, both going down solidly to just under 40 hz or so.  They also have almost the same diameter driver, so it just wouldn't have much to offer in terms of additional bass.

The Feastrexes are extremely fast and plentiful on their own in the bass dept. and can be elusive and tough to keep up with with "any old sub."

However, I do think its very much possible to get a good pairing between a Feastrex and sub, as evidenced by a quick "plug in" of the woofer bank at Doc B's place the last time I brought them over for listening, which was pretty encouraging in terms of performance.  Doc had one of the nicest sounding tube crossovers I've heard running the system.  It think that this piece of hardware made all the difference that day and I'm pretty stoked to go hear it again.

Why woof?

The reason to use a woofer with the 5"ers would be to get far greater power handling and SPL's if that happens to be the taste of the listener.  The ear's own EQ changes as volume increases, and the need for low bass to be louder than the rest of the mix increases as average listening levels top ~95db or so (to me) in order to be perceived as "flat" to the ear.  This can be challenging for any 5" driver to keep up with above 10+ watts when its already making its own 32 hz (and few millimeters of confident, yet ultimately limited, excursion).

Now for me, personally, it is purist fullrange all the way with these drivers because I like nearfield and midfield listening with most speakers, especially the 5"ers.  One SET, one voice coil.  "Uni" is partly an homage the concept of "unite," "unification," both in terms of the sound of these drivers, and the strength of the design team that is behind them in Japan, and also over here in the US as PJ, PB, and Dan have all helped us immensely in the rekindling of this project. 

The Feastrexes in our new cabinets are so coherent, and they make so much good bass when run full range in most listening environments that most people could rest assured that they'll more likely than not make more than enough excellent bass from even a few watts. 

However, a hidden capability of these drivers that few people have ever really been exposed to is that they can make absolutely crazy SPL'S without any compression if the low frequencies are sent somewhere else.  Their magic is still there as tweeters/midrange/low mid wide rangers. 

Another cool feature of all field coil drivers is that you can vary the voltage slightly (+ or - 10%) in order to tune the drivers to a specific sound system.  The high frequency presentation changes slightly in addition to bass character ("lean," "balanced," or "plump"), and this adjustment can prove to be a tremendous asset to be able to compensate for a slightly rolled off phono cartridge or to alternatively take the edge off of an un-optimized digital system. 

The highs of the driver are slowly rolled off above 5k and this is a trait that is inherent to the sound of the drivers (like the Orcas, but there is a greater rolloff on these Feastrexes because they are intended for higher volume playback where the ear becomes more sensitive to high frequencies.)

I personally find the rolloff to be well executed.  A breath of fresh air.  Others who have experience with vintage drivers like the Altec 755A and E know that there is a seductiveness to this kind of sonic presentation if its done well.  If the highs that are there are accurate enough, the ear still seems to be able to prioritize them enough psycologically that they are most certainly "heard."  And while the roll off would appear to be pretty dramatic, the highs and even uppermost highs are paradoxically (to what these measurements would suggest) totally audible to my and others' ears as many things in the mix do definitely "shimmer" but they never "bite."  There is an uncanny ease and accuracy of presentation that these drivers have at all frequencies.  They "Uni-te" the music.

However, if one wanted to add a tweeter to the mix it would be very easy to do.

One could dial back the field coil voltage a bit to bring the efficiency more in line with a 92-93 db tweeter, which also softens the highs in a pleasant way to get a pre-rolloff before a crossover comes into effect, for instance.  Alternatively, one could turn the voltage up even beyond 10% to get the rising frequency response of typical fullrange drivers, up even more and they make excellent tweeters! (but be careful to not go too crazy as the drivers get hot (and it's eventually impractical))

With exotic fullrange drivers like this, it can be initially tough to get used to the idea of their being malleable on a fundamental level but still with good, reliable results.  In many senses, the sole fact that you've paid way more than normal for a set of fullrange drivers (not considering the cabinets), means you've probably gotten more capabilities than you might have thought.

Just like the Orcas, just like the design philosophy of Bottlehead amps, we are actually pretty open minded about how people use our speakers in the real world, so long as we are giving the vast majority of folks something that works extremely well as a simple "plug and play" pair of speakers that have an inherently good frequency response with SET's all the way down to any old amp you've got lying around. 

So while for Molly and I, the 5" Feastrex in a "single driver" configuration with the beepre and paramounts is our "mega system" in the realm of completeness of resolution and holography and chest pounding, "goes through you" sort of bass presence and clarity off of 2-10 watts per channel. 

But as with any sound system, even one employing 4-15" woofers (which we also have in our listening room!), there will eventually be limitations in bass power handling.  The limitations inherent to the purist's single driver approach are ones that I am personally OK with for my own listening - just like the power limitation in the much less expensive, and much less loud, Orca fullrange.

Molly and I personally prefer long term low to medium volume listening to be a completely engaging yet relaxed sound especially in the high frequencies.  Now - I'm not talking about "slippers and cigar" kind of backgroundey loungey musak boringness.   Whether I'm sitting at the edge of my seat or bleary eyed at midnight sinking into the couch, I just want all the detail and none of the "edge."  These are speakers for musical study and/or deep enjoyment or deep healing without any listening fatigue.  We've built the heart of our business around these kinds of speakers and customers because we feel that this is a market sector that, traditionally, has not been served very well by the majority of modern speaker offerings. 

To Molly and I, really good HiFi creates this needed "safe space" for thoughts to unfold, profound or casual, to listen actively to the music and to give musicians fewer communication barriers with their audiences.  Or, more humbly, to just make watching movies and TV a more enjoyable experience. 

Just like the speakers themselves are meant to be simple, transparent, and calmly go about the business of projecting their sound, it's our goal as a business to be transparent and give our all as dedicated woodworkers/manufacturers bringing our best to the production processes that are necessary to achieve this level of quality and control.  It all goes hand in hand.

Cheers,

Clark
« Last Edit: November 16, 2013, 03:00:33 PM by Clark B. »



Offline Clark B.

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Reply #496 on: November 18, 2013, 08:14:40 PM
Listening a bit more over the weekend I am starting to think that I'd like to play with some HF reinforcement with the Feastrex Alphas.  While I know that my own taste is for pretty mellow highs, I can already tell that most folks, especially those in the age demographic to be able to afford the Unis are going to want some sort of high frequency reinforcement to these drivers.  When you've been a music appreciator your whole life you tend to need a little extra high frequency information up top and there ain't a damn thing wrong about that it will probably happen to me some day too!  And our designs simply must serve the tastes of the appreciator, so its with no hesitation that I'll begin experimentations on this.  Perhaps I'll end up with something as mellow as the Fix or perhaps something else entirely.  It will be a challenge, like everything, but totally worth the effort once we nail it.  Luckily, I happen to have a brand new pair of Fostex T900A's (the big boys) to play with for a few days before I'll be installing them into the Cain and Cain Double Horn BEN ES as well in the next week.  If memory serves, these should sound a whole lot better than my old T90A-EX tweeters of yore.  Will report back soon on the preliminary results.

Best,

Clark


Offline xcortes

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Reply #497 on: November 19, 2013, 02:21:15 AM
The t500a mkii are way better than the 900. The only tweeters that are better sounding to me are my plasma tweeters from Doc but those have spl limitations. Would be great with the feastrexes. I'll try them ind day with the WE.

Xavier Cortes


Offline Clark B.

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Reply #498 on: November 19, 2013, 09:27:30 AM
Xavier, totally agree with you about the T500A MK II.  Its probably one of the only horn tweeters that I can really get behind (that's not Goto or ALE!)  And the price is pretty decent considering the massive amount of brass and precision machining (and, of course, the sound for the dollar). 

I have heard some ribbon tweeters at Paul B's place while we were monkeying around with the Mark Audios and those sounded very good as well.

It will be cool to hear about your results with the WE's!



Offline tdogzthmn

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Reply #499 on: November 19, 2013, 01:46:51 PM
Clark,

Did you find the Mark Audios to be too hot in the treble to fit into the "Blumenstein house sound"?  Just curious what the drawbacks were sonically with the Alair drivers and why not use some of Fostex's larger full range drivers?



Offline Clark B.

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Reply #500 on: November 21, 2013, 05:13:39 PM
Hey Thomas, I've been writing up a response yesterday and in spurts today but now need to finish my important rewiring work on these for a customer before I took a night off to finish taking and compiling a few more impressions.  And I also might want to weigh in on the performance of these actually pretty darned good sounding 208 sigmas to review along side the rest.  It may be a little bit of cabinetry magic going on though... These are Terry's first pair of double horns afterall.  Dated June of 2002.

Pouring a little out for my homie,

Cheers,

Clark


Offline jpsimons

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Reply #501 on: November 21, 2013, 06:30:15 PM
John Simons here, my first post I think.

Interesting to hear about high frequency reinforcement on the Alphas, Clark. It's my personal belief that the highs are where music really lives. It's what gives the energy to music rock, it's where so much of the detail is. And the Orcas would support that claim; they don't go very low but still they're the most pleasant speakers I've ever owned, and I really could make due with them the rest of my life. Bass? Bah, nice to have but not that important.

I also have this theory that "relaxing" highs aren't about how loud or soft they are, but how they're distributed. The Orcas go way up over 20khz, which makes the highs smooth. Speakers that barely get to 20k, you have turn them up to hear the highest highs, the shimmer, and then the rest of the treble bites you. The Orcas never poke at my eardrums no matter how much I turn them up, and yet they're bright. They have a lot of punchiness.

Given my particular sonic preferences, I'd be awfully curious how the Alphas sound with more voltage than Feastrex recommends...

Analog: Rega RP6
Digital: iPhone 4
Amp: Fi X 2A3 w/ KR tubes
Speakers: Blumenstein Orcas


Offline Grainger49

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Reply #502 on: November 22, 2013, 09:18:11 AM
John, and the forum,

I asked Clark to recommend a supertweeter for my Orcas some time back.  His comment may be unrelated, but... there is always a but.  I have had my hearing tested and discovered that I have normal hearing up to 5k Hz. then it rolls off by 5dB and remains level above that. 

20 years in heavy industry, noise levels similar to Paul Joppa who worked for an airplane manufacturer, have taken its toll on my hearing.  OSHA mandated hearing protection is insufficient for guys who like audio.  I want something to replace the highs to where my system still has the sizzle of cymbals that I remember in my twenties.  I could hear 19.5k Hz reliably.

Obviously I need something a good 5dB more sensitive than the Orcas and a good 4uF first order crossover for a nominal 8 Ohm tweeter.  I am currently using some cheap supertweeters that lack the elegance of the Orcas.  I turn them off when friends younger visit for a listen.  The supertweeters are just for old farts with damaged hearing.



Offline Grainger49

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Reply #503 on: November 22, 2013, 09:42:26 AM
On to listening impressions....

Last night I had an old friend over.  He owns one of the Record shops here, Raven Records.  We had a couple of drinks, dinner and came up to a very well warmed up system.  I was a little disappointed by the bass response of the double Dungeness subs.  He wanted to hook up the Boston Acoustics sub. 

Then I noticed the bass went through some dramatic changes as I walked to my seat.  I moved him forward about a foot and a half and all was well.  My seat was in a notch in the room's bass response. 

Today I listened to Van Morrison's Moondance, Chicago Transit Authority, first LP, and now The Cowboy Junkies Trinity Sessions.  Nope, I didn't hear the horrendous room rumble from the air conditioner.  I haven't heard that for a long time.  Speaker changes for better imaging and soundstage have lost that ultra low noise, and it is just noise.  But the electric bass on Chicago's first album was very satisfying.  Moondance sounded like he and all the musicians were here behind the speaker line.  The bass drum and boomy old electric bass on CJ's Walking After Midnight is realistic. 

I set them up just as specified by Blumenstein's site and haven't felt the need to touch the knobs since.



Offline Clark B.

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Reply #504 on: November 22, 2013, 10:19:34 AM
Hi John,

Great to see you on here!

I agree with everything you say about the highs of the Orcas. Not to toot my own horn here too much, but it is no small feat to get a $40 driver to sound like this in the HF department.  Alot of the "coolness" to their final character owes to our tuned rubber bushing method of dampening the stamped steel driver frame, and the lack of any damping material in the cabinet as a result.  The use of nice plywood that's been heavily braced (Birch or bamboo) also helps quite a bit too in the highs.

With the Alphas, what's so key about them is that they don't seem to have a "parasitic resonance" sound to them after they've warmed up.  Its pretty easy to shape or add to this sort of raw ingredient into something that would suit people well.  Much more difficult to seemlessly "calm down" a "nervous nelly."

Though, before I monkey around too much with higher voltage with this FC, (which is definitely in the cards), I really want to clean up the field coil wiring from the power supply to the driver with something that's really low resistance and listen closely for the difference in sound now that I'm used to the current paradigm of these drivers in their current boxes, wires etc. and I've got a feel for the way they warm up through the day and behave in general.  Now I've just gotta work my a$$ off patiently to keep putting all the rest of the puzzle pieces together to crack the code.

For instance, the current set of field coil wires I have were (embarrassingly) lengthened to over 20 ft each by soldering 3 lengths together to get each side long enough for a PA gig I did for a singer/songwriter friend a few years ago.  I'd imagine that those extra solder joints aren't doing any favors for the overall performance of those cables in a higher fidelity application though...

Also, I have some nice new low resistance field coil lead wires to try for the runs that are inside the box.  Even switching those out alone should brighten things up in a pleasant way.  When I first tried the drivers on our bench last week, I plugged them in straight to the P.S. with those cleaned up lead wires with the drivers outside of the box, the highs had a noticably clearer tone to them.  Based upon the results from experimentation with cabling in the rest of the system that I did this week that positively affected the response at 10k, it might just be a case of rebuilding pretty much everything in the system really nicely and taking fresh impressions with this 4.5 Volt P.S.

I've played with field coil wiring in the past and it has a similar effect as changing speaker wire to higher quality stuff, but beyond affecting the DCR of the field coil circuit slightly, perhaps desirably "quickening" the relationship between the power supply chokes to be able to deal better with the back EMF from the field coil, I can't offer any other potential explanation as to why FC cabling can affect the sound so much, other than to say that I've heard from other folks who've found out the same about the cabling of these and other field coils.

But something good about the Feastrex drivers in general is that their sound is so robust, you don't need to be too dogmatic about following "the rules" with voltage, tweeters, cabinets or etc. :) 

As soon as we get these Cain & Cain BENs in crates and shipped off after the weekend, I'm going to lock myself in the shop and work on refining these Alphas over thanksgiving.   They still need more hours to be put on them before I can consider measuring the FS of the driver itself as well.  Based upon the bass performance that's still been opening up, I am expecting a slightly lower number than the whizzered versions for sure.  For a 5" driver, this is definitely something that I am excited about!

Cheers,

Clark

Still compiling notes from the Mark Audios before I post results from the ~ year or so of experimentations with them


Offline Clark B.

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Reply #505 on: November 22, 2013, 11:25:24 AM
Grainger,

I don't care if my customers are old farts or not, I just want to make speakers that work for their ears and musical tastes!  So a supertweeter or boost of some sort seems like a very natural addition for folks with any significantly attenuated high frequencies in their hearing.  My philosophy with a "mass market" fullranger like the Orcas is to make something that is more likely than not going to work well for everybody in its "nude" state, just plugged in and played satisfyingly with almost any sort of amplifier without any tone controls engaged.   Or alternatively, you can look at it as the fact that they are close enough to "right" that the folks who know themselves to be outliers in the bell curve of frequency response in human hearing can slightly "shape" them to suit their individual taste.  But in general, you probably want to start with something pretty stinkin' good before you try to band-aid your way to perfection ;)

I'm glad to hear about your Double Dungeness opening up.  I'd suggest trying floor placement as well to get the lowest notes coming in stronger or perhaps the floor placement might help deal with any nodes in your room's frequency response. 

Also, though this is something super basic that I'm sure you've already troubleshooted, (and I hope its not insulting to your intelligence to bring it up!) is to make sure that the polarity of the subs' input wiring is correct.  I've had it wrong a time or two before I noticed what was wrong.  And I was duly embarrassed.

I've also learned from extended use (and customer feedback) that both gain and frequency adjustment knobs should be set at just a tiny bit below the 10 o clock position (9:45-9:55) with most floor placements.  The drivers get more efficient as they break in and eventually you'll need slightly less gain in the amps than you would when the drivers are fresh.  In some ways, I've noticed that a tiny little bit less gain from the double subs integrates better from a psycological standpoint, though the margin for what constitutes "slightly soft" is really slim.  I usually just tune them patiently and gradually by ear from that initial 10 o clock position to what sounds the most natural with all kinds of music.  Then I almost never find myself adjusting them to suit different genres of music or anything.  They just seem to finally "click" together at around 9:45-9:55 after several months and I just end up prettymuch forgetting that there's a sub(s) playing at all. 

One more thing to look out for as well is that the knobs on the sub amps are actually lined up with the lines on the dials.  Sometimes these get put on "a tick" off at the factory.  To get them set correctly, turn the knob all the way down and see if the tick mark on the knob lines up really closely with the first line on the dial.  If it is not lining up, then the knob can be pulled off and put back on in the correct position.  We almost always catch this discrepancy before we ship, but it might be worth a check in case we forgot as it could slightly affect the "stereo" aspect of the bass in a double sub arrangement.  For example -  if one of the subs' knobs were one tick off this could mean that your "visual" match of the knobs (for stereo subs) could be a little different from the actual match of the acoustics.  Its an easy check to make anyways.

One reason I like double subs is that you can ever so slightly compensate (if you need to) for assymetrical room placements that are often unavoidable in modern (I.E. socially acceptable) listening environments.  For instance, one sub in the corner, one out in the room.

Cheers,

Clark
« Last Edit: November 22, 2013, 11:33:19 AM by Clark B. »



Offline Clark B.

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Reply #506 on: November 22, 2013, 01:57:39 PM
On to listening impressions....

Last night I had an old friend over.  He owns one of the Record shops here, Raven Records.  We had a couple of drinks, dinner and came up to a very well warmed up system.  I was a little disappointed by the bass response of the double Dungeness subs.  He wanted to hook up the Boston Acoustics sub. 

Then I noticed the bass went through some dramatic changes as I walked to my seat.  I moved him forward about a foot and a half and all was well.  My seat was in a notch in the room's bass response. 

Today I listened to Van Morrison's Moondance, Chicago Transit Authority, first LP, and now The Cowboy Junkies Trinity Sessions.  Nope, I didn't hear the horrendous room rumble from the air conditioner.  I haven't heard that for a long time.  Speaker changes for better imaging and soundstage have lost that ultra low noise, and it is just noise.  But the electric bass on Chicago's first album was very satisfying.  Moondance sounded like he and all the musicians were here behind the speaker line.  The bass drum and boomy old electric bass on CJ's Walking After Midnight is realistic. 

I set them up just as specified by Blumenstein's site and haven't felt the need to touch the knobs since.


Grainger, Glad to hear that you've got the Dungeness figured out now.

Cheers,

Clark

Edited: initially I misinterpreted Grainger's message

« Last Edit: November 22, 2013, 02:36:09 PM by Clark B. »



Offline Grainger49

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Reply #507 on: November 22, 2013, 03:37:10 PM
Clark,

Last week the whole system was out of relative phase.  I knew when noting imaged in the center I had something wrong.  There are always 2 or 3 voices or instruments around the center spot. 

The phasing on the tiny wire for the Dungeness Subs is hard to see.  I think I got them right but will double check tomorrow.  I'll also try a stack of Dungeness - stand - Orca.
« Last Edit: November 23, 2013, 02:30:22 PM by Grainger49 »



Offline Clark B.

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Reply #508 on: November 22, 2013, 05:39:05 PM
Thomas,

After writing up and looking over my notes and impressions on the Marks, I realize that the only information I really need to convey is actually pretty simple.  Like you mentioned, the Alpair 6P, 10P and 12P just weren't suited to fit into our "house sound" of high frequency presentation - just yet.   Now these are still better than many fullrangers for the price, and the bass is just great and was easy to get from all the enclosures we built and especially so in the heavily braced and double thickened 3/4" bamboo "final" cabinets we came up with for them.  So I definitely do respect the following behind these drivers.  They are gonna suit somebody's tastes, just not mine, nor the local customers and close friends I demonstrated them to over the past  several months.  So for now we've determined to stay true to the search for exactly what we want in a mid priced FR and to keep an eye on this brand into the future to see the newer models they come up with.  I especially have to applaud Mark and his team for overcoming a significant health challenge last year and coming out on the other side making drivers that are better than ever.  There aren't enough people in the industry that care as much as these guys. 

The other Fostexes are probably another story for another day, but of course their reputation as being "hit and miss" is well deserved.  I promise I'll do a good writeup soon because I probably owe it to our community to share my impressions on them in a concise and easy to follow essay of some sort.  There's a partial writeup of these impressions in a discussion in another thread about alternative drivers for the Abby cabinet.  Because of my proximity (pure luck) to Cain and Cain in the early days, I got to bring home or buy and prototype with almost every model of fullrange driver that Fostex has made since 2001, even many of the Japan only special editions, and lately even a pair of the old style (whizzer cone) sigmas with the darker paper just showed up, awaiting impressions to be taken. 

But I can't do any of this work with my hands just a-hangin' out on the keyboard.  Gotta go!

Cheers,

Clark

Edit: spelling.
« Last Edit: November 22, 2013, 05:44:10 PM by Clark B. »



Offline Grainger49

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Reply #509 on: November 23, 2013, 02:42:46 PM
I checked tonight.  The subs are in phase.  I didn't try moving the Dungeness subs to the floor yet.