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Topic: Did you think of horn for REps-1 ?

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Posted by Dominic on 11-15-2006
Not to be too presumptuous but i thought i'd start a thread that could serve as a repository for lowther comments, ideas etc.

the impetus for this was that rola experiment i mentioned in the cogent rmaf thread. I was thinking hmm, 'hard', 'shouty' that's what they say about lowthers. Around these days i'm on a bit of a multiway horn bent more because of the way life has worked out i'm in a position to try the idea. My impression of the ideal shares certain things with the cats but differs in some others. For example my idea of a fundamentals channel requires that it get under a bass singer's voice and over a sopranno's in a perfect world i would stretch that to certain other instruments but reaity being what it is. So in my various researches i've found few usefull drivers to cover that. I'm figuring a lowther-type driver (reps, loth-x, aer, FS,) without a whizzer and an appropriate phase plug for each desired bandwidth would allow for a kind of continuity. I remember reading in one thread or another that Romy thought little of the idea of using a lowther for midbass, but i don't see this as likely if you do a proper frontloaded midbass horn for the job, perhaps running fullrange that makes sense. of course i can't really Say because i haven't heard a lowther yet.

on a slightly differnt note i think the latest developments at Lowther proper are misguided, the driver was designed to be hidden deep in a very large horn and loaded on both sides, and people have been putting them in backloaded 'horns' with the front side acting as a dirrect radiator so no wonder they complain about shoutiness, you need that to get the hf through a gigantic bent horn.

hope i didn't mix anything up too much.


p.s. I just noticed the FS people (some sort of strange offshoot from AER) now has a field coil model Stick out tongue wonder what that would mean for sound.

Posted by Gregm on 11-16-2006
...if you want to use it "pure" as it were, without any in-between equalising. Or you could tailor the amp accordingly. I would see a lowther working well mid-high rather than mid-bass.
My experience is limited, however, to EX-4 used with wizzer in a 150 tractrix (because that was available), driven full-range, then cut through amp. Of course a back chamber is necessary.

Now, even there, there was a relatively linear -but rising - response, to ~12kHz. The wizzer still plays its role and you can hear & measure a (small) bump somewhere around 2,5-3,5kHz. Using a tweet, makes this much more linear and less "shouting"/"hard"/etc to the ear.

OK. But then , the problem is what drivers does one ultimately choose to play around that Lowther, and how? It would be interesting to have some one try this further.

One implementation I heard has the ex-4 coupled with a supravox-400 used as upper bass/ midbass -- but in an onken. Hmmm. I get the feeling that the supra may be ready to marry the lowther, but not quite in those circumstances: the bass voice is OK, the tenor has a few problems, the soprano is ok. Interestingly, cymbals and tympani are ok. So, lowther upwards in the freq range is OK, feasible at least. Downwards seems to be a problem.

It would be nice for s/one with professional interest to work this out using readily available items like the lowther, the supravox, etc.

Posted by Romy the Cat on 11-16-2006

Dominic, I did not use Lowtheres on my own and am familiar with Lowtheres only by observing of what other people do. Unfortunately, among what I have seen. Lowther was used in some strange ways. For whatever reasons people feel that absences of a crossover is very desirable thing and they sacrifice a lot to pursue this pointless desire. Also, a typical use of Lowtheres in a back loaded horn. Still, if even to leave aside the abstract problem with back-loading then the it is impossible to deny a fact that most of those back loaded horn are juts wrongly implemented horns, mostly with undersized mouths (Cain & Cain, Beauhorn, etc...) Are the undersized mouths a typical Lowther’s problems? Hardly only! However, the stupidly undersized mouths make the Lowther installations out there to sound very ugly and I do not add any credit to Lowther-minded people.

I never believe I advocated use of Lowther for upperbass. However, I never felt that Lowther is horn drive either. What I feel that Lowther might be a good direct radiator if it use in a relatively narrow frequency range. The best sound that I heard form Lowther was in Hørning loudspeakers were Lowther was used as MF driver.

http://www.goodsoundclub.com/TreeItem.aspx?postID=960#960

Still, I feel that Hørning use Lowther too low and complimented Lowther with VERY unfortunate bass implementation.

Anyhow, I did not play with Lowther myself and therefore I do not feel that this thread is something where I might contribute anything valuables. In the Lowther world I specialize only in bitching about what other people do wrong and recognizing how horrible their Lowther implementation sound.  That all did not motivate me to do anything with Lowther myself.

I find Lowther is too simple driver to ignite my interest. What I said “simple” I implied that even after spending efforts and learning how to get out of Lowther any more or less civilized sound the result might be still at sub-qualified level and might be easily beaten by other drivers.

Rgs,
Romy the Cat

Posted by Dominic on 11-16-2006
Ah yes that was the thread. You mentioned that the lowther was used too low on the hørning
 because a lowther could not honestly be used for a midbass.
What i was thinking is that due to its design and retarded power to weight ratio it could be plausible to use lowthers in all of the horns but the most high. With all of them being front loaded and full size. I really do agree that lowthers have to date not been used with any sense, and of all things, how on earth is a driver with a rising response supposed to be better as a dirrect radiator.

i'm starting to think that the sentiment you express in the last paragraph is very common and perhaps comes from the plethora of misguided implementations. the driver was designed to work with the original enclosure design which was a very large front horn:

cross section-
exterior-
if anyone shows interest i'll translate the description

 In a way it's like a corner loaded A7 with priority given to the horn rather than the BR section. if you look at it's no wonder there seems to be an inherently tipped up balance in the Chave design as it's essentially the Voigt design. THe DX drivers are to me an abomination forced on the company by the afforementioned misguided implementations.

Posted by Paul S on 11-17-2006
IMO, with care  the Lowther DX4 does pretty well from 150 to 10k Hz.; but it is as colored when "loaded" by a horn as anything else.

The "notch-filtered" DX4 driver is pretty natural in an OB within its "easy" range, lacking only the last word in drive available from an "ultimate" 4 or 5-way multi-amped, multi-horn system.

IMO the Lowther DX4 is the cheapest, easiest way to get most of what a mega-multi-horn system offers.

IMO the Lowther DX4 sucks as a "full-range" driver.

With Lamm ML2s I get fairly accurate ensembles and listenable 18th-19th century symphonies when I run this driver 150 Hz.- 10K Hz in a large OB.  IMO, a Lowther driver must NOT be asked to handle bass, and it trails off above 10 K Hz, if anyone cares.

Basically, considering it's limitations, I currently think the Lowther DX4 is the best-value "wide-range" driver  I know of.  I use it in a 3-way system with notch filters.  I am not sure the DX4  would be "better" in a 4-way system.

Paul S

Posted by Romy the Cat on 11-17-2006

I think you’re onto something in it. Those Lowthers in fact might be not unfavorable candidates to use with horns at all.  An open baffle at 150Hz? Perhaps, although I do not feel that Lowther can handle that exertion with a necessary integrity, and partially in opened baffle.

There is something else; witch is actually more disturbing to me in Lowther. Whatever Lowther implementation I have seen and heard (including the opened baffles) all of them suffer from one very characteristic for Lowther behavior: Sound getting emaciated, almost choked with raise of sonic complexity.

You were in a way correct restricting the Lowther use for 18th-19th century music; I would probably correct it to 17th-18th century music. However, even within a sonically simpler music the Lowther tendency to “collapse” from complexity still is well noticeable. I would not emphasize only sonic collapse – it is musical collapse as sounds are loosing their associations with each other and reproduce result do not sound like music any more but rather as an array of notes. Interestingly that most of the Lowther devotee that I have seen in fact did love that disassociated, doted Sound and chased that sound religiously.

In the end it bolides down to what you need. There is “Sound” and there are “the sounds”. It is possible, at least form what I have seen, to let Lowther reproduce “Sound”, if music is simplistic and do not play louder then 80dB. The Lowther will be fine for a jazz trio plays in over-damped recording studio. For anything more complex it might, from my point of view, require more complex acoustic system solutions.

The Cat

Posted by guy sergeant on 11-17-2006
I have a cousin who is autistic. He is happy most of the time but he isn't really able to communicate his feelings to anyone else.  He is also a very talented musician who plays the violin & piano very well. There are many interesting aspects of this disability but one is that it can give an insight into the potential of the human brain albeit often in only one direction such as mathematics or music.

There are some items of audio equipment that also give a glimpse as to what might be achieved although in other ways they are invariably flawed. The flaws might even be might even occasionally be the cause of the virtue.  I regard the Lowther PM4A in this way. (I don't like the DX drivers at all.) I agree that it, like most Lowther drivers has serious deficiencies and is not and cannot be a universally applicable solution. however there are some things it can do which no other driver I've heard can do. For me it sets a standard with one or two of its attributes and for that reason it is interesting. I suppose this is the reason why so many listeners persist in using Lowther drivers despite their obvious shortcomings. I gave up after several years.
 
The Decca cartridges (when working!) are another flawed design which hint, in one area, what might be done.

I'd be interested to hear any other suggestions for products that give a glimpse at what might be.

Posted by slowmotion on 11-17-2006
IMHO one of these drivers that make you listen to the music at first,
but something isn't quite "right".
Put it on a - big - open baffle and cut at 200 and use maybe up to 2500Hz.

Problematic with female voices, like opera and so on.

It distorts quite a lot.

I had best results with cutting of the whizzer, taking away the phase plug
and using some felt on the polepiece. Don't try to force it to extend the frequency range upwards. Make it sound good in it's natural (mid)range,
and use something else for top and bottom frequencies....

Many years ago now, so I don't remember exactly.


I haven't heard the new models.

Just my personal opinion.....

cheers

Posted by yoshi on 11-17-2006

I've been having love/hate relationship with Lowther (and its siblings) for several years now.  As you all say, it has many problems to use as a full-ranger.  Right now, my set up is a 3way multi-amp, Lowther (Reps 1) in Medallion cabinet covering up tp 1k, JBL 2450/2397 for 1k~10k, TAD (Pioneer)  RT8T for over 10k.  The crossover is 2 x TOA 0204 (digital) right after the transport (all 12db Bessel) and DA is done by TOA's internal DAC.  This is a digital only system since AD/DA completely screws up whatever advantage the system has.

I had to cut the upper limit of the Reps at 10k because of the nasty peak at around 2.5k~3k (seems inherent to all Lowther type drivers, except AER which seems to have flatter response).

Even with the limitation and the confusion of the backload horn bass, the system does OK for me when playing sources with not much dynamic range.  I love the immediate and tactile feel of Lowther.  But when you put an orchestra on, the whole thing collapses at ff.  Specifically, the mid-low to low muddiness becomes unbearable.  Also, it can't catch up with the dynamics.

I'm hoping to improve the situation by adding woofer for below 2~300.  Any suggestions/recommendations are appreciated.

Yoshi


Posted by Paul S on 11-17-2006
Perhaps there are ways to horn load Lowthers that do not screw up the sound, but I don't know of any, and there are other reasons, as well, for not asking LF from Lowthers.

For me the best thing about the high-pass-limited Lowther DX4 in OB is that it does a fairly accurate job of replicating  instrumental and voice pitches and timbres, within its frequency and dynamic limitations, of course.  One of the main reasons I quit working with horns is their colorations.  Horn loaded Lowthers I have heard share this problem, so I gave OB a try, and I also limited what I ask from the Lowther, in order to get as much of its best as I could.

IMO, for best use of Lowther, do not feed it LF.  LF seriously overloads the thing and the collapse Romy notes happens a lot sooner when the Lowther attempts LF.

I realize that many Lowther users "like" what amounts to its thinness.  I do not; in fact it drives me nuts, so I passively trimmed its 2.4k and 8k Hz frequency spikes.  Doing that and adding LF speakers and HF drivers brought pitch, timbre, weight and scale back into line, right along with superior clarity, focus and MUCH better dynamic range.

Of course the Lowther DX4 will never match compression driver SPL.  But it can comfortably do well up into the 90s if LF is kept out, and I happen to prefer its more liner dynamic quality to the "tromboning" of compression driver/horns, where the dynamic quality varies so much according to frequency and also varying "within itself", changing as it changes, if that makes sense.

As for HF, the Lowther does not get worse as it rises; it just trails off, and its HF needs help, just like its LF.

Yes, the Lowther has big problems; but I found them easier to mitigate than the horns' problems, at least to get as far as I've gotten with them to date.

Paul S

Posted by Datubie on 11-21-2006
I've had a pair of PM4 and GOTO SG30W sitting by cupboard for several years now and instead of just watchinng the foam rot on the Lowthers, I was thinking of slapping the lot into a sealed box for fun. The PM4 would have it's own chamber of course. For starters I was thinking of running the GOTO up to say 400 to 500hz and the PM4 from there on up. I've also got several ribbon & horn tweeeters to try should they be necesary. The room is pretty small at 18ft by 15ft, so I'll need to keep the size down as much as possible. Thoughts anyone?

Posted by Tom Brennan on 11-21-2006
 When I was in Paul Klipsch's museum in Hope several years ago ole PWK had several of those large upright Voight front horns such as Dominic posted and many Lowther-Voight drivers. Perhaps the old coot liked the things or found them interesting at least.

Posted by Paul S on 11-21-2006
I confess that at one point I tried PM6As in 2.5 cu. ft. vented boxes.  Lousy, tipped-up balance and soggy, one-note "bass", contrary to the designer's claims.  The only thing good about it was that the box did not add color like Lowther horns I've heard.  Having been through this, I decided that a small sealed box, maybe 1 - 1.5 cu. ft., would be a better way to do it; just high pass the Lowther and add notch filters to bring down the 2.4k and 8k spikes, top it off with a blended-in tweeter.  No way to tell what the box loading would do to the PM4As character until you try it.

Biggest problem I see with it is deciding the best compromise for a low pass and/or LF crossover.  Many have reported extreme difficulty getting bass that meshes seamlessly with the Lowther.  I cross at 150 Hz, bass chores handled by a 15" Audax P380MR.  I cannot hear the difference crossing with that woofer at that frequency.

Best regards,
Paul S

Posted by Romy the Cat on 11-21-2006

So, you are thinking about 3-way installation with GOTO bass, Lowther mid range and some ribbon atop? It is certainly no one knows how I might end up: try it, post the pictures and let know us how it went.

I can see a few points where you might need “working”…

1)  Deduct what to cat the Lowther/ It will be quite complex as you will need to find where GOTO will be go down quality-of-sound-wise and where Lowther will be able to take over. It will be in particularly complex because the performance of the drivers will depend form the type of the enclosures. For instance if you put the Lowther in open baffle then what size do you need to target the baffle: 400Hz, 550Hz, 700Hz? Only God knows… Whatever it will be it might very difficult to synchronies a sealed box with Lowther. I personally never heard Lowther sound good with any separate bass channel.

2)  Only God knows how good GOTO ay it’s HF knee. The driver is around mid 30s resonant frequency and it sealed bit it might hardly do well in upper bass. Still is the room is small then it might… It would be very cool to put a pair of GOTOs in array wings with open-baffled Lowther between them… Then, where to stick the ribbons? Once again… the only Allah knows…

3)  The higher you begin to use ribbon then better it will be…. but the Lowther do not do well above, I would say, 7kHz

But it is juts me…
The Cat

Posted by Gregm on 11-22-2006
IME (i.e. some pm's one dx), the Ex-4 sounds the most civilised -- and this, only up to ~10kHz or 1-2kHz lower.

It doesn't sound bad in a tractrix, unlike Paul S' experience with a dx4.

A horn is also useful to provide some extra spl (106 spl at 1+m with a tractrix) -- see below:

(following fm immediately above) It's spec'd at 100W, but should be maxed at ~5W, maybe 6. (maybe even 7? 10? Forget 50)

You MUST cut off the mid-bass downward, or it'll poof at the fff -- and you'll lose whatever detail is in upper mids.

Again, mating it with s/thing doing the job fm say 150/200 (better), etc, on down and whatever, 7-8kHz, up is a pain. Esp. the down.

Posted by Datubie on 11-22-2006

Thanks for all the replies.

I've got a fellow hornie friend who knows someone in the Japanese GOTO agency who can understand English. I'll try bouncing the idea off theem & see what they say.


Posted by Romy the Cat on 11-22-2006

Datubie,

I do not think you should have a lot of expectations from Japanese GOTO office. I do not know how about the drivers but I would doubt their practical experience in system engineering. Their exponential trumpet horns are very poor. Their “ready to go” systems are laughable. The GOTO and ALE sell very few LF compression drivers per year (if any) and mostly to very “specific” people. Therefore, I would not expect them to be “interesting” from “applied design perspective” …. or perhaps it is just my attitude). I would personally treat them as “drivers source” if you like their drivers but how you use their driver I think your own brain will figure out faster and more profitable. Perhaps you want get it touch with Kevin Brooks. He is a big GOTO and ALE enthusiast and I have seen him humiliating himself with Lowther as well. Perhaps he has some experience with combining them.

http://www.kbrooksaudio.net/photo.html

You generally might make some assumptions seeing how GOTO used that own bass driver. Frankly speaking I do not think it should be a lot of different from any other driver of the similar suspension. If it has soft suspension then treats it as 15” Altecs and afraid excursion (juts with a pair of GOTO drivers you have very little leverage to mange it). If it has hard suspension then treats thsm as 14” Kangfilms and afraid the bass softening during the  bass transients…

Still something suggests me that those Japanese folks did not intend to use this SG30W in a seals box as you’re planning. Japanese people do not like sealed boxes. Sealed box is fundamentals-centric machine but Japanese people are harmonics-centric.

http://www.GoodSoundClub.com/TreeItem.aspx?PostID=1959

I think that most likely the SG30W GOTO  folks meant to be use their direct radiates in some kind of setting when the drivers will be very running, arousing a lot of noise around itself, something like Onken or Ultraflex enclosures… I do not know if Lowther will be doing fine in “noise” world. With all Lowther evils it is not necessary a “noisy” driver….

Rgs,
Romy the Cat

Posted by Dominic on 02-16-2007
it doesn't appear to me that Lowther's own designs hold any real potential.
As some might figure, i'm partial to Voigt's original intentions, and i think those have been covered over.

I post now because i had an idea.
I see the lowther as a pseudo compression driver, an open rca 1428 in paper sort of.
Anyway, i was wondering if anyone out in the wide world had tried a lowther type into a plane wave tube. Since that is the common method of measuring a compression driver, this would seem a logical course of action, at least from my perspective.

Posted by Paul S on 08-13-2007

I realize that some people have been raised from infancy with the Lowthers, take them to bed, etc., so I do not mean to do anything here other than air some recent thoughts on the subject and perhaps get a discussion going about these drivers and possible further “evolved” uses for them.

I wound up with the Lowthers after starting with horns, then going to sealed, then planar speakers (briefly), then back to sealed, this over 40+ years.  I liked and still like some things about each of these topologies, and, honestly, I have stayed with what I have considered the least problematic speakers, hoping for a nice cost/benefit ratio in my dotage.  So shoot me.  But if you know or have heard the litany of Lowther Problems, then you know one is up against it when deaing with these suckers; it is still no cake walk and no End of the Rainbow, for that.

Actually, I have had some very particular positive reasons for doing as I have done.  I have for some time wanted to wind up with instrumentally-correct pitch, timbre, weight and scale, and this has been my main priority – but not my only priority - for some time.  The early modular  Fultons were fun toys for years, and remarkable in terms of pitch, timbre, etc., incredibly colorful, but too slow and vague to stay with when their cheap-o crossovers started to go and the old drivers wanted re-coning.

What I wanted from the Lowthers was fast Fultons, but it was not to be so simple as that.  While they do not have quite the palette of the old original Fultons, I find the DX-4s rich in color, quite dynamic for cones, and possessed of a certain “gestalt” that other drivers just lack.  And I find it truly remarkable how wide a frequency and dynamic range the Lowther can do its stuff with.  None the less, .IMO, the Lowther does not do “full range”; period.  Also, attempts to use horns to amplify the Lowther severally color the sound, so that is out for me, too.  And oh, yes: the notoriois "spikes" at 2.4k Hz and 8k Hz.  So, what do you do with these temperamental little near-misses?

I started thinking “wide range” rather than “full range”, and "tame the spikes", soon after I started with the Lowthers.  I tried a few options for growing the available range, but by the time Dick Olsher introduced his OB “BassZilla”, it actually made sense to me.  Also, by the time I got mine built, Dick had figured out that Lowthers should not be fed anything under 150 Hz., and he had added a ribbon tweeter to augment the Lowther’s whizzer, which trails off above 10k Hz.  A tweaked “final” version of Olsher’s design, the Diamond Edition BassZilla, is what I now use.

I like the relative absence of colorations, and I like the dymamics, within their limits (more, anon).  The BR bass is compatible with (if not a perfect extension of) the Lowther DX-4.  The ribbons I am now using go up as high as you’d want, and they are probably as good as or better than available amps.

Plusses: good pitch, timbre, weight and scale; surprising dynamics (for cones); nice imaging; excellent articulation; nice, big listening area; can be driven with SET***.

What’s wrong?  I will always take more color(!); has a gelatin ceiling on dynamics, at least with the ML2s; can’t really be driven to best advantage with one SET/channel, IMO.

So, here I am, open to fire on a horn-ish website.  Where do we go from here, guys?  I am futzing with the crossovers, then I am +/- whether to add amps or veer South to warmer climes.

Best regards,
Paul S

Posted by Bud on 08-14-2007
Paul,

And any one else that is interested in what may be a new leaf in the Lowther book.
Please go to the first post. This is from a participent in this forum. He may choose to speak up and he may not.

http://www.diyaudio.com/forums/showthread.php?postid=1269281#post1269281

This next is from Jon Ver Halen of Lowther America. There are a number of short posts following this one with some test data from Jon on what will be at the RMAF, as the main show speaker.

http://www.diyaudio.com/forums/showthread.php?postid=1275431#post1275431

This last is Jon's final commentary on what he is discovering. I invite you to email him for private conversations and perhaps discuss what you want and what he is comfortable with to meet your desires, for more than you curently have, from your current driver.

http://www.diyaudio.com/forums/showthread.php?postid=1276391#post1276391

I realise this sort of location is anathema to most here, not all by the way. Feel free to participate in any way you are comfortable with, there is a lot of information available and if you look just a little you will find all you need to treat your own Lowthers with, for about $40 in materials and a few emails. You won't be buying the materials from me, by the way.

Bud

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