I have been wondering about this. I have seen much speculation that there are not significant differences between the unity patent, and the synergy patent, and even James Croft expressed surprise in his patent column when the synergy patent was granted.
1) is it the confusion between the differences between the two patents that is stopping people from exploring unity?
2) what are the differences between the two? (I have seen people (mostly connected to Danley) talk about the differences, but seemingly only to cover tracks, not to really educate.) (I have admittedly not searched out this information, just come across it.)
I guess that I can say anything and it's invisible...(to certain folks)...
See http://www.diyaudio.com/forums/multi-way/294382-synergy-horn-flat-pack-4.html#post4869239
Basically, the second patent, US8284976 assigned to DSL, is not different because it isn't distinguished from the first patent--US6411718, assigned to SPL--in its IP. (I wonder how it got through the patent office, in point of fact, because it cannot patent the same IP.)
The passive crossover of the DSL Synergy horns is talked about but is never detailed in the patent, so it wasn't actually patented.
The rest is up to the patent lawyers to argue. (I wouldn't want to be DSL trying to upstage the SPL Unity Summation Aperture patent.)
See http://www.diyaudio.com/forums/multi-way/294382-synergy-horn-flat-pack-4.html#post4869239
Basically, the second patent, US8284976 assigned to DSL, is not different because it isn't distinguished from the first patent--US6411718, assigned to SPL--in its IP. (I wonder how it got through the patent office, in point of fact, because it cannot patent the same IP.)
The passive crossover of the DSL Synergy horns is talked about but is never detailed in the patent, so it wasn't actually patented.
The rest is up to the patent lawyers to argue. (I wouldn't want to be DSL trying to upstage the SPL Unity Summation Aperture patent.)
The extensions of the horn beyond 1/4 wavelength will affect the HF directivity--and in a good way. The only concerns are impedance bounces due to irregularities and discontinuities. And you can't hear the harmonics of fundamentals that are above 10kHz.
Perhaps you failed to read the information on the K-510 horn, along with its directivity vs. frequency plot. (That's okay.)
...and yes, directivity is actually more important in smaller "small rooms" than in larger "small rooms" due to early reflection issues affecting human hearing processes more strongly.
Chris
Update: I got this dialed in, it was easy. I'm running the horn down to 500Hz, with a pro 15" + sub below that. It is nice. I recommend it*
As a mono system, it plays satisfyingly loud in a big workshop, with a listening distance ~5m.
The OP, if listening in stereo in their tiny room should get effective SPL at least 10dB higher than what I'm hearing. That should be plenty, assuming the OP has more than a few watts available**.
You can get the NE65W-04 from Parts Express or Digi-Key.
The horn mentioned in post 15 should be fine for this. It is also cheap and located reasonably close to the Philippines - I dunno if that helps with the "direct couriers" issue.
Horn Flare Large Format 2" Throat 4 Bolt Mount
The total cost for drivers & horns would be ~$ 200 AUD or 8,000 PHP.
*I don't recommend everything I buy. I have a lot of stuff on the shelf cos it wasn't good enough / wasn't right for the intended project. I've also tried several drivers on this horn, including a 14kg compression driver.
**my listening was with this amp
Dayton Audio DTA-120 Class T Mini Amplifier 60 WPC
For an inexpensive horn, that's probably one I'd use. It tests fine.
But I'd use it only if lowest price is the requirement...
The smaller horn is the K-510, which has much better performance in terms of polar control:
Chris
Attachments
The horn profiles and mouth roll out are different. One uses a straight-sided horn with unknown coverage angles and either an exponential or truncated tractrix flare.
The other uses a straight-sided horn section with full tractrix flare, plus "mumps" in the corners (a patented horn feature) which controls the "waist-banding" near the horn's axial fc. It was designed to hold its polars more constantly vs. frequency.
The two horns look similar, but they're really not--at least in terms of their performance.
The other uses a straight-sided horn section with full tractrix flare, plus "mumps" in the corners (a patented horn feature) which controls the "waist-banding" near the horn's axial fc. It was designed to hold its polars more constantly vs. frequency.
The two horns look similar, but they're really not--at least in terms of their performance.
I guess that there is a problem using the English language on an international forum. I said nothing about phase plug design of compression drivers. If that is what you consider to be of higher importance than the lower midrange upwards through most of the treble frequency band in terms of directivity, then I'd recommend starting another thread on that subject.
Me...I'd simply look for another compression driver that is higher performing to mate with my 2" throat horn.
Anything above 7-8 kHz is controlled by the compression driver phase plug. I thought that was "common knowledge"...Perhaps it isn't.
Chris
Me...I'd simply look for another compression driver that is higher performing to mate with my 2" throat horn.
Anything above 7-8 kHz is controlled by the compression driver phase plug. I thought that was "common knowledge"...Perhaps it isn't.
Chris
The above plot was done in the Klipsch anechoic chamber in Hope AR using a K-402 horn and a B&C DE75 compression driver...which is not exactly what I'd call a "high cost" driver, but rather one that they used on their base-level commercial cinema products. They now use a B&C DE750 driver, which they call a K-691 driver. I can post plots of that driver's performance if required. It performs well.
I'd actually recommend considering the Faital Pro HF200 series drivers for home hi-fi use, at about the same cost or perhaps even lower, depending on your geographical location.
Chris
I'd actually recommend considering the Faital Pro HF200 series drivers for home hi-fi use, at about the same cost or perhaps even lower, depending on your geographical location.
Chris
Is this better performance something you've measured?
In some comparisons, the cheap / generic horn has had better polars than the 'impressive' one, e.g:
trying Pyle PH916 constant directivity waveguide: first impressions | MiniRIG
The user rates and measures the Pyle as slightly better than the more expensive Faital equivalent.
HF144 with FaitalPro LTH142 and Pyle PH916 – outdoors directivity measurements | MiniRIG
I like the look of the "mumps".
Apparently the secondary flare on the synergy horns is there for the same reason.
Hi hollowboy, the peerless driver i am using with the horn is the 830983, it is passively crossed over with a 15uf cap along with a resonance peak suppressor cct to tame the drivers resonance peak (BTW the driver is mounted open backed) and for the bottom end i have it matched up with an old modified AR28(?) 10" driver/box set up, and with a bit of treble boost the set up sounds quite nice.
cheers, Arthur
PS i wonder where the op went?
cheers, Arthur
PS i wonder where the op went?
The driver I got looks very similar. They probably put the same motor and cone onto a slightly prettier (aluminium) frame.
Are you able to take / share measurements?
You could try using a stuffed, open ended tube (aperiodic loading) as an physical means of removing the resonance peak ...but I have no idea if that'd sound any better / different to using a passive circuit.
I've been wondering too.
Maybe they wanted a one-line answer, and can't be bothered reading all this rambling
Yes, i take measurements (i am still using Bill Waslo's IMP (since 1996) because it is easy to use and i cant be bothered/or have the time learning all the new measurement software that i have installed on my PCs, i think even if i used and stuffed an enclosure for the driver it will still have a peak that would need treating, an L a C and an R is quick and easier than making an enclosure
Yes. I think that the anechoic polars of the Klipsch K-510 are already posted for the vertical direction. The horizontal direction is better. If you're recommending the other horn, I assume that you already have its polars. They're okay.
The point I was trying to make is that there seems to be a large DIY appetite for not-the-best horn profiles--because the horns are cheap. Contrast that to the subject of passive crossover components, where everything's under the microscope in terms of "their subjective sound".
I've seen that before (and you probably have too), and it's very much like the proverbial story of the drunk looking for his car keys under the streetlight because the light's better over there--instead of looking where he dropped his keys. The concept of balancing one's focus on the most important acoustic elements first (even if those subjects are difficult) in order to achieve better system performance is apparently alien. I could write a book on that subject (and I probably will at some point, as a matter of time). This effect seems to be a common affliction in this particular pastime. I personally find that there's a lot of bad information about horn design and performance floating about.
Dual flare straight-sided horns partially address the waisbanding issue, but actually create an impedance bounce issue--among other effects. They also don't perform nearly as well as--for instance the K-510 horn profile--in terms of polars vs. lower frequencies...by a large margin.
Chris
I bought a box of these about ten years ago and they were my favorite small driver. The surround on every last one cracked.
There's a handful of small drivers with a rising response above 5khz. These are great for horn loading because the rise offsets the drooping treble that's typical of constant directivity horns.
TL;DR:
My own preference (in the absence of local sellers of quality parts) would be to get a cheap horn, then apply some DIY effort to mimic the good features of nice horns like the K-510.
Exact words:
It was an just educated guess. The pyle I just linked, the horn in the pi speakers whitepaper, and several others are very simple designs that have good polars (published). My educated guess was that the generic horn, being very simple and very similar in appearance, would have equally good polars.
That's a valid point - in isolation. However, cheapness of the horn itself isn't the only factor. Other big ones are:
1) This is a DIY forum. I like to DIY, and unless told otherwise, I assume that anyone else posting here is happy to do some work with their own hands.
Therefore, I like getting a cheap, undersized horn that's just 'okay', and then making it better.
2) postage can blow out the project time and costs. The OP, in the Philippines, mentioned two horn suppliers, both European. This can be slow - sometimes extremely slow - and adds considerably to the expense.
A recent example: I ordered some Scan Speak drivers which I thought were in a local retailer's inventory. This was 15-Dec-2016. They actually shipped from Europe, and arrived at my house on 13-Jul-2017 (yes: 210 days later), by which time I had mothballed / changed the project.
Experiences like this tilt me very heavily towards locally available products.
3) I think I've shipped gear from the USA four times, and two of these deliveries have arrived with parts broken. For me to send something back and then wait for a replacement takes a lot longer (and more $) than it will for a US resident.
Now put these factors together: my best case scenario for a cheap horn is that it arrives in a few days, then takes a few hours of DIY tweaking to make it perfect.
My worst case for a US or Europe sourced product is that postage doubles the item cost, delivery takes >100 days, and the item is broken in transit.
I'm snipping the rest, not to be dismissive, but because I agree. Money and effort are best spent where it makes the most difference.
I'd be pleased if you could counter some of this bad info:
Could you please show the polars of the K-510 vs those of the cheap horn?
If my educated guess was wrong, I'd like to know why / how much.
My own preference (in the absence of local sellers of quality parts) would be to get a cheap horn, then apply some DIY effort to mimic the good features of nice horns like the K-510.
Exact words:
It was an just educated guess. The pyle I just linked, the horn in the pi speakers whitepaper, and several others are very simple designs that have good polars (published). My educated guess was that the generic horn, being very simple and very similar in appearance, would have equally good polars.
That's a valid point - in isolation. However, cheapness of the horn itself isn't the only factor. Other big ones are:
1) This is a DIY forum. I like to DIY, and unless told otherwise, I assume that anyone else posting here is happy to do some work with their own hands.
Therefore, I like getting a cheap, undersized horn that's just 'okay', and then making it better.
2) postage can blow out the project time and costs. The OP, in the Philippines, mentioned two horn suppliers, both European. This can be slow - sometimes extremely slow - and adds considerably to the expense.
A recent example: I ordered some Scan Speak drivers which I thought were in a local retailer's inventory. This was 15-Dec-2016. They actually shipped from Europe, and arrived at my house on 13-Jul-2017 (yes: 210 days later), by which time I had mothballed / changed the project.
Experiences like this tilt me very heavily towards locally available products.
3) I think I've shipped gear from the USA four times, and two of these deliveries have arrived with parts broken. For me to send something back and then wait for a replacement takes a lot longer (and more $) than it will for a US resident.
Now put these factors together: my best case scenario for a cheap horn is that it arrives in a few days, then takes a few hours of DIY tweaking to make it perfect.
My worst case for a US or Europe sourced product is that postage doubles the item cost, delivery takes >100 days, and the item is broken in transit.
I'm snipping the rest, not to be dismissive, but because I agree. Money and effort are best spent where it makes the most difference.
I'd be pleased if you could counter some of this bad info:
Could you please show the polars of the K-510 vs those of the cheap horn?
If my educated guess was wrong, I'd like to know why / how much.
That's terrible, but good to have forewarning of.
Did you push them hard, or was is simple aging / drying that did it?
What are they?
I'd love to find something with an upward tilt, that is also just as smooth + extended as these little 2" units.