Danley Signature Series are for sale now:
https://www.sweetwater.com/store/de...ries-hre1-4400-watt-4-way-powered-loudspeaker
https://www.sweetwater.com/store/de...ries-hre1-4400-watt-4-way-powered-loudspeaker
It's all business I guess... it may even start (or be able) to compete with this one:
https://www.genelec.com/8381a
https://www.genelec.com/8381a
My experience has been that class D amplifiers and horn-loaded loudspeakers (even hybrid horn-direct radiating bass loudspeakers like the model being discussed in this thread) is not something that I'd imagine is a naturally good combination. Even Hypex NCore NC400 seems to have issues on the small-signal end of its performance:
https://community.klipsch.com/index.php?/topic/202006-minidsp-shd-power-hypex-nc400-class-d-amps/
If considering Hypex FusionAmp modules--my subjective experience with FA122s on a SH-96-sized horn was appalling:
https://www.diyaudio.com/community/...a123-with-old-mtm-towers.394294/#post-7229947
I would hope that the amps servicing the HF Synergy Horn portion of the HRE1 might just as likely be class AB instead of class D for the reasons discussed above. If they're class D--at the prices being shown in the advert above (i.e., 50% higher than a Klipsch Heritage Jubilee--which itself I believe is an insanely high price...at least 5x the manufacturer's actual building costs), I would hope to see something other than class D module boards internally for home hi-fi use.
The clarity and sensitivity of the horn-loaded portion of the loudspeaker design magnifies the weakest part of class D amplifier operation (the part that direct-radiating loudspeakers typically isn't audible due to their >10x lower power efficiency). I'd be skeptical of any class D modules driving the Synergy Horn--reportedly an SH-60 without reflex ports inside the HRE1--for home hi-fi duty.
YMMV.
Chris
@Cask05
If you have done the comparison with a class AB or A that measures with extreme low distortion?
The question is whether the amp is so transparent that is revealing flaws in the speakers (and possibly acoustics of the room) or if it's a mismatch for some reason.
As I'm sure you know, the higher distortion with Hypex is suppose to be above the audible range or it happens if the amplfier has to output a lot of power in the treble - something that doesn't happen for home use.
If you have done the comparison with a class AB or A that measures with extreme low distortion?
The question is whether the amp is so transparent that is revealing flaws in the speakers (and possibly acoustics of the room) or if it's a mismatch for some reason.
As I'm sure you know, the higher distortion with Hypex is suppose to be above the audible range or it happens if the amplfier has to output a lot of power in the treble - something that doesn't happen for home use.
You apparently didn't read Langston's posts, above in the first link (or mine in the second link).
The problem is the inverse of what you describe--the lower distortion of the compression drivers (mostly intermodulation) vs. using the drivers in direct radiating mode.
This problem is not the passive drivers, but apparently rather the active amplifiers (class D) in the microvolt and below region.
Chris
The problem is the inverse of what you describe--the lower distortion of the compression drivers (mostly intermodulation) vs. using the drivers in direct radiating mode.
This problem is not the passive drivers, but apparently rather the active amplifiers (class D) in the microvolt and below region.
Chris
I've read the Langston's thread. I wouldn't say that's convincing. His NC400 amp measured great. In the listening session he first experienced great sound but came to the conclusion that it sounded somewhat dry. He went on with an ABX test but he didn't level match within 0.1dB, so that's not a valid ABX.
Several people in the same thread boasted about how well different Hypex or Purifi amps sound. So basically different subjective experiences. Or did I miss something?
I have never tested the Hypex FA122, but I do know that Hypex amps with low distortion doesn't sound anything like you describe on horns. I would think that must a have a bad apple. BTW: The Hypex DSP in their plate amplifiers isn't 100% transparent, but I doubt that's the cause here since the experience was so bad.
So, if you want to call him incompetent, that's your prerogative. However my experience is that he is one of the more thoughtful, careful, and knowledgeable people that posted on matters related to the present subject. I know the experience levels and the dial-in quality of the others' systems in that thread. I think I'll stick with Langston's published data and subjective comments on that subject. I found his observations and opinions to be spot on in the past. That's why I referenced that thread.
I do think it must be a cultural difference to so openly ignore or to dismiss others' posts on technical matters, such as the current one. This isn't the first time for us. I know that in my profession (mechanical and systems engineering >45 years), that you do that with great caution and deference for other opinions, and not outright dismissal of their findings without even a mention of doing so, or using specious arguments to dismiss them. To do so is considered at least impolite in my geographic area. [FYI--in case you were wondering why I'm taking the time to explain.]
[By the way--on another subject--I contacted about 25 of the people that I've worked with/helped about your horn offerings. I hope that at least one or two of them showed some interest.]
Chris
I use class-D amplifiers on horns (EXTRON XPA2004) but I also attenuate the compression driver with a passive network and run my amplifiers at the minimum gain required to get full output with my DSP. I have run a wide variety of amplifiers in the past including Crown CTS, Yamaha P5000/P7000, Apart audio, Cloud, beyond differences in noise floor and perhaps the Crown CTS 4200 sounding a bit 'brittle' (perhaps under biased?) they have mostly sounded the same. I would agree though that connecting a compression driver directly to an amplifier is a recipe for requiring some expensive electronics!
If we look at a high performance amplifier like the Purifi 1ET400A is has an a weighted output noise voltage of 11.5uV so with a 110dB/2.83V1. speaker the speaker will output 2.17dBA/1m noise so noise is not likely to be an issue even without attenuating the compression driver. What could be more of an issue in this hypothetical DSP->AMP->HORN system is that the voltage requited for the compression driver is very small and as such considering the amplifier gain the DAC on the DSP has reduced performance due to not using its most significant bits, this reduces the SNR but also there is a whole host of non ideal behavior from DACs at the bottom of their range such a spurious tones and output correlated tones which are not captured well in normal testing which I think are a bigger issue. I have a battery powered system that has a low performance DAC (DSP and DAC one chip) using digital attenuation to reduce volume, this system sounds pretty garbage at low volume with 100dB/1W speakers (desktop use), beyond the hiss you can also make out tones in the noise, my thoughts are this somehow makes the music playback less pleasurable. At high volumes this system sounds fine though.
To mitigate issues like this in my home system I attenuate the output of the DSP to match the amplifier. However this issue is independent of amplifier class and would also apply with a class A/AB amplifier and would typicaly get worse with a higher power amplifier due to their greater closed loop gain. Simply claiming a perceived issue is due to a large open loop gain in the audio band is not correct, this is a well known technique to improve performance and is a principle also used in high performance class A/AB amplifiers (and small signal electronics like OPAMPS). I would refer back to Harold Blacks original paper for clear examples. I would actually speculate a class-D amplifier could have better small signal performance than a class-AB as their is no discontinuity around 0V (crossover region).
If we look at a high performance amplifier like the Purifi 1ET400A is has an a weighted output noise voltage of 11.5uV so with a 110dB/2.83V1. speaker the speaker will output 2.17dBA/1m noise so noise is not likely to be an issue even without attenuating the compression driver. What could be more of an issue in this hypothetical DSP->AMP->HORN system is that the voltage requited for the compression driver is very small and as such considering the amplifier gain the DAC on the DSP has reduced performance due to not using its most significant bits, this reduces the SNR but also there is a whole host of non ideal behavior from DACs at the bottom of their range such a spurious tones and output correlated tones which are not captured well in normal testing which I think are a bigger issue. I have a battery powered system that has a low performance DAC (DSP and DAC one chip) using digital attenuation to reduce volume, this system sounds pretty garbage at low volume with 100dB/1W speakers (desktop use), beyond the hiss you can also make out tones in the noise, my thoughts are this somehow makes the music playback less pleasurable. At high volumes this system sounds fine though.
To mitigate issues like this in my home system I attenuate the output of the DSP to match the amplifier. However this issue is independent of amplifier class and would also apply with a class A/AB amplifier and would typicaly get worse with a higher power amplifier due to their greater closed loop gain. Simply claiming a perceived issue is due to a large open loop gain in the audio band is not correct, this is a well known technique to improve performance and is a principle also used in high performance class A/AB amplifiers (and small signal electronics like OPAMPS). I would refer back to Harold Blacks original paper for clear examples. I would actually speculate a class-D amplifier could have better small signal performance than a class-AB as their is no discontinuity around 0V (crossover region).
It's an all-in-one design.
Arguably, the major advantage of this speaker isn't the sum of it's parts, it's that Danley Sound Labs was sidelined by the pandemic for a while there (broken manufacturing pipelines and Covid restrictions) and they used their time to design the heck out of a loudspeaker.
I believe I'm probably one of five or ten people who've heard a Danley SH-50 back-to-back with a Lambda Unity Horn, and though the two look similar, they sound very very different.
I attribute a lot of this to refinement of the concept, and the Danley Signature Series is basically months and months of painstaking refinement of existing parts.
If Danley was selling cars, this would be like comparing a Porsche GT3 to a fifteen year old 911. Sure, they look similar, but they perform much differently.
I haven't. My comments here relate to the general architecture of class D amplifiers vs. class AB or even class A.
To sum up what I'm saying here in my comments, it seems to be relatively more difficult to do a good job in class D (a lot more difficult) than the current SOTA for the other topologies for horn-loaded loudspeaker duty. That's basically it. I think that the user must make up their own minds, i.e., caveat emptor applies. I relate my experiences here only for the benefit of others that might be thinking of doing the same. I do think that it would be prudent to consider buying amplifiers that can be returned for full refund if considering class D, etc.
I can relate my experiences with regard to others on the forum(s) that seem to be quite insensitive to the fact that well-designed horn-loaded drivers are typically at least 10x more efficient (based on input/output power to equal SPL)--and closer to 100x more efficient--than their operation in direct radiating mode, and that threshold effects for amplifiers like the ones I related above actually exist and can be a real issue with much higher efficiency loudspeakers. That's why I commented here.
However, my experience with Tom Danley designed loudspeakers and other hardware has been uniformly good, if constrained to the knowledge that his offered equipment is mostly optimized for fixed PA duty (present case excepted). I would only recommend extensive A-B auditioning the HRE1s before buy if they are completely powered by class D. The buyer can make up their own minds whether or not the amplifiers and loudspeaker design/integration itself is up to their standards for home hi-fi duty. Most home hi-fi enthusiasts I know buy their own amplifiers and integrate with their loudspeakers, so powered loudspeakers remove that "degree of freedom" for hi-fi enthusiasts.
Chris
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Gain structure is very important. One way to avoid the above mentioned problem with having to use a DSP/DAC in it's lower volume settings, is using a small but excellent amplifier for the compression drivers. F.e. I use a <1 watt tube amp -with the bonus benefit that the output transformator is blocking DC, so you don't have to be afraid of frying the drivers with DC offset in case of trouble and you don't have to use a protection capacitor which may degrade the performance.