Another candidate for a Synergy mid driver?
I came across this relatively new sealed back mid driver from Precision Devices. I have not heard the driver, but based on the specs it seems to be a monster of a 6½" sealed mid driver
. It is not exactly cheap though....
PD.615WG
Best regards
Peter
I came across this relatively new sealed back mid driver from Precision Devices. I have not heard the driver, but based on the specs it seems to be a monster of a 6½" sealed mid driver
. It is not exactly cheap though....PD.615WG
Best regards
Peter
In my projects, I've found that the woofer is generally the weakest link, then the tweeter. The midranges are just loafing along.
This is the reason that I generally use 2-4 very small woofers; I don't need more.
The reason that the woofer is the weak link is that the woofer isn't horn loaded; it runs out of steam first.
I've usually found the tweeter is the weakest link in my designs. The constant directivity horn means that the tweeter driver's naturally rollled off response has to be equalized flat again, so the sensitivity that results is what the tweeter does at its highest frequency and without help from further horn directivity/beaming (that many elliptical horns cause). So, realistically, 95dB/1w/1m at 8 ohms is about what an overall passive design gets. Using small tweeter CDs, of course, could be higher with something like a FL450 driver.
So, I go for the smallest practical mid drivers (2"D ideally, maybe 3"D if only using two mids). Not a lot of reason for larger, and larger get a lot more difficult to use.
So, I go for the smallest practical mid drivers (2"D ideally, maybe 3"D if only using two mids). Not a lot of reason for larger, and larger get a lot more difficult to use.
I am planning to build my first "full" Synergy horn. I have some test models built already. How low should I worry about pattern control of the horn. This is for a 3 way system for mostly Home Audio and maybe the rare block party type of thing.
I was thinking in the 200-250Hz area? I used the Synergy Calc. XLS and came up with similar Size horn as the Danley SH-69.
I was thinking in the 200-250Hz area? I used the Synergy Calc. XLS and came up with similar Size horn as the Danley SH-69.
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Ik have a very old phillips woofer 8 inch, it did this in the synergy.
port 7 cm from the throat, as you see it go above 1000 Hz.
But I go on with the tractrix horn, will on a day go try these synergy also, keeps me busy.
regards
port 7 cm from the throat, as you see it go above 1000 Hz.
But I go on with the tractrix horn, will on a day go try these synergy also, keeps me busy.
regards
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I have fallen victim to building Synergy Horns!!!!!!
I plan to start a full build now that I have tested the waters with a few test builds. I will open my own thread soon enough. I am not sure what I plan to do yet. I have thought of building 2 x SH-96HO or building 1 SH-96HO and 2 SH-60F type speakers. This would be the building block to a HT. I dont have room for a good HT right now so I am more interested in just building two stereo speakers.
Just to let you know what I am working with:
8 x MCM 55-2981 cast frame 10inch woofers
MCM Audio Select 10'' Die Cast Professional Woofer - 250W RMS | 55-2981 (552981) | MCM Audio Select
12 x GRS 5SBM-8 Sealed back mid
https://www.parts-express.com/grs-5sbm-8-5-sealed-back-midrange--292-432
2 x D250 Dayton Polymide CD
https://www.parts-express.com/dayton-audio-d250p-8-1-polyimide-compression-horn-driver--270-402
I think this could represent some great bang for the buck. With the qty discounts that would be $200 per speaker for a high output 3 way horn.
I figured I would dump this teaser post in here as it has become kinda all things Synergy Horn
Steve
I plan to start a full build now that I have tested the waters with a few test builds. I will open my own thread soon enough. I am not sure what I plan to do yet. I have thought of building 2 x SH-96HO or building 1 SH-96HO and 2 SH-60F type speakers. This would be the building block to a HT. I dont have room for a good HT right now so I am more interested in just building two stereo speakers.
Just to let you know what I am working with:
8 x MCM 55-2981 cast frame 10inch woofers
MCM Audio Select 10'' Die Cast Professional Woofer - 250W RMS | 55-2981 (552981) | MCM Audio Select
12 x GRS 5SBM-8 Sealed back mid
https://www.parts-express.com/grs-5sbm-8-5-sealed-back-midrange--292-432
2 x D250 Dayton Polymide CD
https://www.parts-express.com/dayton-audio-d250p-8-1-polyimide-compression-horn-driver--270-402
I think this could represent some great bang for the buck. With the qty discounts that would be $200 per speaker for a high output 3 way horn.
I figured I would dump this teaser post in here as it has become kinda all things Synergy Horn
Steve
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Mine sound fine, better than the econowave standard (selenium d220ti). The Celestion might sound better,but since I haven't heard them, I can't comment
To each his own, I guess.
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New Danley offering in the works, Ivan mentions it here:
official danley sound labs thread - Page 10 - AVS | Home Theater Discussions And Reviews
official danley sound labs thread - Page 10 - AVS | Home Theater Discussions And Reviews
I don't know if throwing around negative reviews without backup info regarding the Dayton CD's is fair. My experience with all Dayton branded products has been very good and I think they offer some products with high quality value and features that will sometimes cost you 3x the price with another brand. They have a good return policy too. What exactly about the Dayton CD's makes them unsuitable for a synergy?
As examples try to find another driver that matches the RS225-8 for about the same or higher price. Look at the PS95-8 driver: cast frame, copper shorting ring, inverted surround, phase plug, paper cone, nice sound for $23. Look at PA130-8 for $18 - superb sound and great sensitivity in a rugged package that is unpretentious. Look at the RS100-4 for $27 same thing with allow frame but anodized aluminum cone and shorting rings and low distortion. I could go on. I don't have the CD in question but can't imagine that it wouldn't sound decent - as Zobsky agrees.
As examples try to find another driver that matches the RS225-8 for about the same or higher price. Look at the PS95-8 driver: cast frame, copper shorting ring, inverted surround, phase plug, paper cone, nice sound for $23. Look at PA130-8 for $18 - superb sound and great sensitivity in a rugged package that is unpretentious. Look at the RS100-4 for $27 same thing with allow frame but anodized aluminum cone and shorting rings and low distortion. I could go on. I don't have the CD in question but can't imagine that it wouldn't sound decent - as Zobsky agrees.
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I've gone into this in more detail in some other posts, but here's a summary:
First off, all compression drivers have limited bandwidth. In order to improve the low frequency cutoff, something has to give, and compression drivers that can handle a low cutoff suffer in the top octave. (10khz+)
Even Danley can't engineer around this. When I rented the SH50s, the imaging knocked my socks off, but the treble on my homebrew Synergies was noticeablly cleaner. The compression driver that Danley uses costs $150.
If everyone agrees with me so far, then you'll wonder "how do we fix this?"
The answer is simple : use a smaller compression driver.
The compression drivers with small diaphragms run circles around the DE25, DE250, the Parts Express knockoff, etc.
Even better, they're cheaper!
At this point, you'll be thinking "there's no free lunch, what's the catch?"
The catch is that you have to move the xover point up.
But in a Synergy horn, this is incredibly easy. The B&C DE250 can happily live with a 900hz xover, like Geddes uses, but we don't NEED a 900hz xover for a Synergy horn.
I typically use a xover around 1500hz.
Once you start using the small format compression drivers, you will not go back. The difference is NOT subtle.
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An externally hosted image should be here but it was not working when we last tested it.
Don't believe me? Just ask JBL. The JBL M2 uses a large format compression driver, with a 1.5" throat. The compression drivers are $3000 a pair. There's some serious engineering in there. Despite all that, reports coming back about their new studio monitor indicate that the small format 2409H measures better than the large format 2430K.
And the price difference is COLOSSAL; $3000 a pair versus about $300 a pair.
It's an excellent illustration of the law of diminishing returns; if you want to squeeze more bandwidth out of a compression driver, it gets painfully expensive.
And isn't that what the Synergy Horn is all about? The whole point of a Synergy horn is to synthesize a point source using an array of drivers, instead of pushing the bandwidth of a single driver.
In previous posts I've published data to back up these claims; you can see the superiority of the small format drivers (when used within their limits) in the CSD plot in particular.
Right now I think the Bill Waslo design is the one to beat.
At this point I've heard the following:
1) piles and piles of Synergy horns that I've built for myself
2) Two sets of Lambda Unity horns in different owners homes
3) Danley SH50s, pitted against my own designs
Bill's Synergy isn't just good, it actually exceeds the original in some respects. He has a heck of a design there.
Back in 2006 I used small format compression drivers and small format midranges because the design was going into a car. Eventually I bugged Danley enough to reveal the midrange used in the Lambda, and I bought a case of them. But after building piles of these things, I realized that there's a tradeoff with the large format midrange and compression driver. You get epic output and power handling, but you pay a price when it comes to transparency.
Basically Bill's Synergies don't sound like horns; they sound like conventional loudspeakers but they image better.