Nectar Hive Review (Electrostatic Headphones)

[nectarsoundnet]

Is it possible you can buy one amp that will satisfactorily drive all electrostats? Which one would you get for that purpose? (maybe Amir would do better to see if he can get his hands on one for any future electrostat reviews)

Sure! Here is a KGSSHV I built! The massive size and power is not just for looks. The KGSSHV operates at a +/-450V rails and has plenty of swing, bias and output capability. The important part is to measure them properly, with an audio analyzer, and then with a scope (because it will exceeds the input voltage of the audio analyzer) and check the distortion. And check it at 1kHz, 10kHz, 14kHz, 20kHz etc..! Don't just do a 1kHz measurement and then an F response, that tells you nothing about the performance of an estat amplifier. I would encourage anyone doing these kinds of measurements to learn about how this technology works, what kind of load you're driving (NOT an inductive load like you're used to) and then make the proper array of tests needed to TRULY evaluate these kinds of amplifiers... The trouble with the KGSSHV is that parts are near impossible to find anymore. I got a chance to speak to the maker of Eksonic at CanJam this weekend, and he knows what he is talking about as well and makes great amps that are worthy of using as measurement equipment and evaluation of headphones: https://eksonic.com/

 

[Dial]

Ouch, how did that happen? I have the same adapter box.... so far no issues...

I don't know at all, yet I wasn't pushing the volume very high at all (because the distortion happens quite quickly). When in doubt and after careful consideration, I dumped the amplifier (more expensive than I had bought it because everything Anglo-Saxon has a strong love rating). Strangely my friend had an electrostatic Koss that was still working ten years ago (we lost sight of each other but he must still have it, he keeps everything).
This led me to buy only devices from my region or country as much as possible (impossible for cartridges for example or only vintage...).

 

[SuicideSquid]

It’s the peaks that will cause issues. For yucks I took measurements while listening to my floor speakers with a cal’d mic and at an average of 85dBA there were 105-108 dB peaks at times at lower frequencies, so you could possibly push them beyond their limits even in relatively normal listening.

As a person who suffers from mild hyperacusis, I can assure you that I never listen to music that peaks at 105-108dB. In a quiet room, I'm never pushing average volume beyond around 75dB, and in most cases that'd be closer to 70dB, with peaks maybe at 90 at the most.

I like my ears and do not enjoy abusing them.

 

[Miiksuli]

Is it possible you can buy one amp that will satisfactorily drive all electrostats? Which one would you get for that purpose? (maybe Amir would do better to see if he can get his hands on one for any future electrostat reviews)

Probably best would be pure transformer with Benchmark AHB2. But the problem is that you can't get hands very easily anymore to something like Pro iESL.

I would want to listen some day the KGSSHV. Probably I would be surprised. It's very expensive thought.

 

[LTig]

Sure! Here is a KGSSHV I built! The massive size and power is not just for looks. The KGSSHV operates at a +/-450V rails and has plenty of swing, bias and output capability. [..] The trouble with the KGSSHV is that parts are near impossible to find anymore.

What about using a standard speaker power amp and a properly sized step-up transformer? I think something like this was used in the 1970's - one of my teachers at that time had a Stax headphone connected to a black box which was connected to the power amp's speaker outputs.

BTW: when I was allowed to play with his Stax I did raise the volume too much and one channel lost signal after making some noise. Luccily it recovered after a few minutes.

 

[nectarsoundnet]

What about using a standard speaker power amp and a properly sized step-up transformer? I think something like this was used in the 1970's - one of my teachers at that time had a Stax headphone connected to a black box which was connected to the power amp's speaker outputs.

BTW: when I was allowed to play with his Stax I did raise the volume too much and one channel lost signal after making some noise. Luccily it recovered after a few minutes.

Xformer boxes (driven by speaker amps), while in theory is a good solution to the efficiency issue of driving such high voltages cleanly, they are fraught with danger which is why most people avoid them. They will just step up whatever you put at the input with virtually no limit, so what they do is they put these voltage suppressors on them, but that still may only limit the voltage to 1400Vpp levels, very high levels and you'll never know if one went bad until it fries your headphones. And the other issue is you now have a not so linear transformer to deal with in your audio path. Finally, some manufacturers don't put the standard 4.7Meg series ballast resistor on the 580V bias (or defeat it with a cap at the end of it) and this fries some headphones as well. I did make some of my own portable, battery powered amplifiers using output Xformers, and still have it. But just not a viable product. Also now you can struggle with driving LOWS properly (opposite issue of a solid state estat amps having trouble with the HIGHS) because now your speaker amp is driving an inductor, and that inductor looks like a short at low frequencies (2*pi*f*L)... So you need quite a bit of inductance and windings on the primary, then a ton of windings on the secondary to step it up. I think Pro iESL probably did the best job with theirs getting around all the issues, just from what I read.

 

[Cars-N-Cans]

As a person who suffers from mild hyperacusis, I can assure you that I never listen to music that peaks at 105-108dB. In a quiet room, I'm never pushing average volume beyond around 75dB, and in most cases that'd be closer to 70dB, with peaks maybe at 90 at the most.

I like my ears and do not enjoy abusing them.

70 dB is actually a fairly low listening level. On the unweighted scale you are easily going to be at 85 dB or so. I don’t enjoy abusing my ears, either, which is why I use a current limited amplifier of my own design that is limited to 20 wpc. That equates to the above levels with large floor speakers and a sub to extend the response. 80-85 dB is a fairly common upper listening level, it seems, for many people. As such, it can still cause damage long-term which is why I give my ears a break after an hour or so. This is not like my cars which went up to around 135-140 dB. That IS loud, and I stopped using those systems. I’ve had tinnitus my entire life so I have no indicators if I am harming my hearing. It’s also why I started putting hard limiters into my amps. It looks like it was a good call as my high frequency hearing is still completely intact. But long story short the SPL levels can be quite high at low frequencies just due to the nature of our hearing.

 

[Robbo99999]

I can't imagine ever wanting to listen to headphones above 90dB, let alone 100dB, but still, what a mess.

As some people have mentioned, there's a difference to measuring a headphone during a sine sweep at 0dBFS vs the level of "loudness" you are exposed to during music. The type of weighting used is a factor, and A-weighting is probably the best to indicate damage to ears and how loud something sounds. The other factor being that music is not at a constant 0dBFS, the recording levels are below that. I measured a typical listening level A-weighted on my loudest track using a miniDSP EARS rig and this is what I got:

So the average A-weighted listening level in the above graph for that track is the purple line labelled "LAeq10m", which was a value of 77dB. So I'd say I'm listening at 77dB there. Whereas if you do a 0dBFS sine sweep at the same amplifier settings you get the following graph, see following graph, and in the following most people would say that's at 84dB as that's the 1kHz point, so you can see that the sine sweeps Amir does for frequency response & distortion measurements are not the same thing as listening levels (instead they're closer to the momentary peak listening levels during a track):

EDIT: post has been edited to include pics that I know are at the same amplifier level.

EDIT #2: and note that this was the loudest track I have that I measured, so the difference between 0dBFS sine sweep and A-weighted listening level in tracks would be greater for an average track, which further illustrates the difference between a 0dBFS sine sweep that Amir does vs the actual amount of noise you're exposed to when listening to a track. So most of the time they'd be at least a 10dB difference between Amir's measured sweeps and your A-weighted dB level on your track - and that's not accounting for any bass boost EQ you've done which could be +10dB bass boost & the corresponding -10dB preamp, which would put the higher dB sine sweeps such as 104dB and 114dB into greater context (makes them more sensible) which you'd use to correlate to just bass distortion in your EQ'd headphone.

 

[Robbo99999]

Sure! Here is a KGSSHV I built! The massive size and power is not just for looks. The KGSSHV operates at a +/-450V rails and has plenty of swing, bias and output capability. The important part is to measure them properly, with an audio analyzer, and then with a scope (because it will exceeds the input voltage of the audio analyzer) and check the distortion. And check it at 1kHz, 10kHz, 14kHz, 20kHz etc..! Don't just do a 1kHz measurement and then an F response, that tells you nothing about the performance of an estat amplifier. I would encourage anyone doing these kinds of measurements to learn about how this technology works, what kind of load you're driving (NOT an inductive load like you're used to) and then make the proper array of tests needed to TRULY evaluate these kinds of amplifiers... The trouble with the KGSSHV is that parts are near impossible to find anymore. I got a chance to speak to the maker of Eksonic at CanJam this weekend, and he knows what he is talking about as well and makes great amps that are worthy of using as measurement equipment and evaluation of headphones: https://eksonic.com/

View attachment 213996

So those Eksonic amps would probably be a more realistic purchase then, due to availability.

Eksonic - Vision within music

To hear pure and complete music without colorization creates an experience that presents all auditory queues available in recordings against a black background so you can place instruments in space. This allows you to experience music as the artist intended and this is the foundation of...

eksonic.com

I noticed they've got some tubes in there, which you can see in the pic. Tubes have a negative connotation here on ASR due to unnecessary colouration of the sound ("euphonic" distortion), is that the same deal with the tubes in these amps?

 

[amirm]

How can anyone perceive any nuances of music at 106 dbSPL?

You will hear the nuances much better as they won't be lost in the noise floor/below your threshold of hearing.

Remember, threshold of hearing is 70 dB at 20 Hz. If you listen at 80 dB, bass would be barely audible. And that is where you need the power and dynamics. No one is talking about 106 dBSPL at 1 kHz.

 

[amirm]

Hi, I thought I'd chime in because the measurements don't really match the feedback I get from most of my customers, and the amplifier used is an SRM 313...

Your posts have focused on dynamics where I clearly mentioned my issue was with the frequency response. Do you have comments about those resonant peaks? They sure seem correlated to me and not created by the amplifier.

 

[nectarsoundnet]

Your posts have focused on dynamics where I clearly mentioned my issue was with the frequency response. Do you have comments about those resonant peaks? They sure seem correlated to me and not created by the amplifier.

Amir, first, I think you do a service to the community especially with objective dynamic driver measurements. Regarding your evaluation of Hive & SRM313 combo, I know you will appreciate how easily it is to get fooled by subjectivity so let me explain what might be happening: You may be seeing my F response of my electrostatic headphones with “resonant peaks”, then saying “aha! That’s the issue” then listening to the HP’s with an SRM313 that will introduce distortion in the high frequencies (please see the scope shots I attached or take your own with a Stax HP connected, play 10kHz or 15kHz and 20kHz and crank up the voltage, you may visibly see the distortion) and then linking what is probably the amplifier distortion issue directly to the “resonant peaks” in your mind. Then you are EQing those peaks out, with a +5dB delta at 2kHz.. So now your SRM313 which you have proven with another post that can only do 114dBSPL with a 3dB more sensitive HP before clipping, has a 5dB handicap. So now it can only go up to 109dB before clipping. Adjusting for 3dB of sensitivity delta with your previous measurement, that is where you get your 106dBSPL limit before clipping (but not before amp voltage distortion at the higher frequencies at high voltage levels).. Now finally both of these facts (amplifier limit as well as amplifier distortion) will explain your comment and subjective experience “Even without the filter, the ability to play loud is simply not there. Go past slight above average listening level and the sound starts to get dirty and congested. Keep turning up the volume and you now start to get mild static to go with that. Crank it up more and hell breaks loose at 3:00 o'clock.” Also this comment in your conclusion: “Fortunately their effect is not large unless a tone hits on them and you hear the sharp zing”… That sharp “zing” you mention is absolutely caused by high voltage distortion in the highs due to a poor amplifier, and much less by frequency response, I know from experience and objective measurements (please see the scope shots I shared). Many customers prefer my $600 HPs over the $3000 SR009 (not reviewed on this site) exactly because it doesn’t have that extra sibilance or harshness in the highs seen by some estats, which is derived from my tensioning techniques, but if you listen to either one with this amp you will experience the same thing. You do make a final comment “with this amplifier I have at least”. Which I truly do appreciate, however that comment is given no weight relative to the overall post, and people will see this as an objective, scientific review of “The Nectar Hive” as you have in the title with, and a picture of only the headphones without the amp, as “Poor” or “not terrible” (on the front page of this forum, with all valid discussion buried) which is the opposite of the sentiment I’ve gotten over the years.. To quote the customer that sent them in for review “I want you to know that my intentions were to spread the word about what I think it one of the best cans money can buy in today’s market” , and this could very well crush my small business I’ve been painstakingly hand building over 200 headphones for the past 4 years, I developed myself for really really happy customers. There is a lot to consider for a proper estat setup, and even though the trouble that goes to perfecting it is not for everyone, I am really happy to have made them more affordable.

 

[Robbo99999]

Amir, first, I think you do a service to the community especially with objective dynamic driver measurements. Regarding your evaluation of Hive & SRM313 combo, I know you will appreciate how easily it is to get fooled by subjectivity so let me explain what might be happening: You may be seeing my F response of my electrostatic headphones with “resonant peaks”, then saying “aha! That’s the issue” then listening to the HP’s with an SRM313 that will introduce distortion in the high frequencies (please see the scope shots I attached or take your own with a Stax HP connected, play 10kHz or 15kHz and 20kHz and crank up the voltage, you may visibly see the distortion) and then linking what is probably the amplifier distortion issue directly to the “resonant peaks” in your mind. Then you are EQing those peaks out, with a +5dB delta at 2kHz.. So now your SRM313 which you have proven with another post that can only do 114dBSPL with a 3dB more sensitive HP before clipping, has a 5dB handicap. So now it can only go up to 109dB before clipping. Adjusting for 3dB of sensitivity delta with your previous measurement, that is where you get your 106dBSPL limit before clipping (but not before amp voltage distortion at the higher frequencies at high voltage levels).. Now finally both of these facts (amplifier limit as well as amplifier distortion) will explain your comment and subjective experience “Even without the filter, the ability to play loud is simply not there. Go past slight above average listening level and the sound starts to get dirty and congested. Keep turning up the volume and you now start to get mild static to go with that. Crank it up more and hell breaks loose at 3:00 o'clock.” Also this comment in your conclusion: “Fortunately their effect is not large unless a tone hits on them and you hear the sharp zing”… That sharp “zing” you mention is absolutely caused by high voltage distortion in the highs due to a poor amplifier, and much less by frequency response, I know from experience and objective measurements (please see the scope shots I shared). Many customers prefer my $600 HPs over the $3000 SR009 (not reviewed on this site) exactly because it doesn’t have that extra sibilance or harshness in the highs seen by some estats, which is derived from my tensioning techniques, but if you listen to either one with this amp you will experience the same thing. You do make a final comment “with this amplifier I have at least”. Which I truly do appreciate, however that comment is given no weight relative to the overall post, and people will see this as an objective, scientific review of “The Nectar Hive” as you have in the title with, and a picture of only the headphones without the amp, as “Poor” or “not terrible” (on the front page of this forum, with all valid discussion buried) which is the opposite of the sentiment I’ve gotten over the years.. To quote the customer that sent them in for review “I want you to know that my intentions were to spread the word about what I think it one of the best cans money can buy in today’s market” , and this could very well crush my small business I’ve been painstakingly hand building over 200 headphones for the past 4 years, I developed myself for really really happy customers. There is a lot to consider for a proper estat setup, and even though the trouble that goes to perfecting it is not for everyone, I am really happy to have made them more affordable.

I really do think, and especially for a headphone that has been developed by one person or a small company, that we should respect their hard work & emotional/physical/monetary investment in such a project by making sure we're using the right amp so as to not misportray the headphone. I would like to see this headphone remeasured with an amp that is agreed worthy by manufacturer & Amir alike.......I think we should try to do justice to the headphone, especially when it's been produced by the opposite of a large/faceless company, as I feel the personal/future stakes for the producers are a lot higher.

 

[OkPsychology]

I really do think, and especially for a headphone that has been developed by one person or a small company, that we should respect their hard work & emotional/physical/monetary investment in such a project by making sure we're using the right amp so as to not misportray the headphone. I would like to see this headphone remeasured with an amp that is agreed worthy by manufacturer & Amir alike.......I think we should try to do justice to the headphone, especially when it's been produced by the opposite of a large/faceless company, as I feel the personal/future stakes for the producers are a lot higher.

This.

I couldn't agree more.

In the interest of full disclosure, I'm an unabashed Nectar Sound fan, and the subject of this review was my own headphone. I didn't really want to get involved in this conversation, as it would look painfully obvious that I have a horse in this race. But I think there have been enough questions raised about the results of this measurement, the methodology employed, and the equipment used to warrant a remeasurement of the headphone. To be quite clear, this goes beyond a simple "taking of an unflattering review personally", or wanting my gear to be reviewed favorably because it's an extension of my ego. Am I disappointed in the results? Ya, of course. But if we're not willing to be critical of our own processes, proceed as objectively as possible, and perhaps from time to time revise our techniques, then we're not really Sciencing are we? To my understanding, that's the whole point of this community, and ASR's reason for being.

@nectarsoundnet has provided ample evidence to support the claim that the findings herein do not accurately represent his product. This alone should warrant a reexamination of the headphone. That said, I've seen on a few occasions here at ASR questions raised about the testing processes have led to a doubling down on the supposition that the original methods were sound. In this instance, however, I do have some hope that we might see another pass at accurately measuring the Hive with an amp that's up to the task.

The way I see it, at this juncture reputations are on the line. Both @nectarsoundnet's and that of @amirm. A mischaracterization of the headphone is potentially damaging to Nectar's business. Furthermore, a failing to remeasure the headphone after solid evidence has been presented that the data is inherently flawed is a stain on ASR's reputation.

Luckily, and as it so rarely happens, there is a win/win solution to the problem with which we are now faced. Let's just remeasure the headphone with adequate amping, no? This seems like a no-brainer to me.

 

[CedarX]

I now better understand the “uniqueness” of this headphone and it’s manufacturer. But I also think the product page is missing clear warnings about the “correct” amplifier selection. From that respect, Amir’s review is perfectly legit. IMO: if I were to buy this HP, I would be pissed to find out after the fact that it only “works” with some specific estats amps, but not others designed for Stax estats (the de facto standard).

 

[Vict0r]

I now better understand the “uniqueness” of this headphone and it’s manufacturer. But I also think the product page is missing clear warnings about the “correct” amplifier selection. From that respect, Amir’s review is perfectly legit. IMO: if I were to buy this HP, I would be pissed to find out after the fact that it only “works” with some specific estats amps, but not others designed for Stax estats (the de facto standard).

Well, he does have a whole page dedicated to which amplifiers are most suitable. There's no warning on the product page itself, though. https://nectarsound.net/commercial-amp/

 

[Zoide]

Also, the SRM-313 came out 23 years ago and was replaced by the SRM-323A in 2006. It's basically 3-4 generations behind the current models.

So unless you're already really into estats you'd have to try hard to even know where to get one, and even then why would you?

BTW, I wonder if Amir's SRM-313 had its capacitors replaced or if they're ~20 years old.

 

[CedarX]

Well, he does have a whole page dedicated to which amplifiers are most suitable. There's no warning on the product page itself, though. https://nectarsound.net/commercial-amp/

Fair enough, but that page only hints at sensitivity & loudness considerations whereas, from previous posts, it appears there is more to it and not every estat amp--even a modern one--is going to work correctly.

 

[nectarsoundnet]

Fair enough, but that page only hints at sensitivity & loudness considerations whereas, from previous posts, it appears there is more to it and not every estat amp--even a modern one--is going to work correctly.

This is kind of where things start getting out of control with this kind of thing on forums. My headphones don't need to be paired with any specific amps any more than any other electrostatic headphone. They will work with pretty much any Pro-Bias estat amp. I even use the SRM1MK2 daily which is an older version of SRM313. I also have a very costly KGSSHV I built myself which gives me much better performance, this is totally normal and applies to any headphone/amp/combo. I've also had many many customers use my HPs with vintage $300-$500 amps and they love it. I honestly don't know how to gauge what Amir wrote when he says "dirty and congested" etc.. I've never heard that from ANYONE. So you're really just taking his word on something subjective. His objective measurements show my distortion numbers were to the floor.. He's doing stuff with EQ then cranking it up to when the amp clips... I've never had anyone report that as an issue to me. And has a youtube video showing some literature saying that 113dBSPL for a piano is normal and won't blow your ears out. I've blasted music on my rig to very loud levels and it doesn't push above 96dBSPL peaks, but I admit I don't have the same expensive GRAS rig he has. Guys, if my headphones sucked and only worked with like 1 amp, I would have given up a long time ago, and not spend HOURS and HOURS building headphones by hand in my spare time. I also understand that electrostatics is a cumbersome technology, for every electrostatic headphone - not just mine! And why is mine the only one being torn apart here?

 

[SuicideSquid]

As some people have mentioned, there's a difference to measuring a headphone during a sine sweep at 0dBFS vs the level of "loudness" you are exposed to during music.

[snip]

Snipped most of your post just in consideration of not having a massive block of text. I appreciate the detail in your response. I'm aware of these issues and admit I was being somewhat glib in my comment re: 90dB levels - there are certainly many scenarios where you can be listening at a reasonable volume level and want headroom over 90dB.

I also maintain that no sensible person should care if a headphone starts clipping, distorting, or simply will not push past 106-108dB. Even after considering that you may need some additional headroom for EQ and factoring in different weighting, etc., if you're listening at a level where you're going well past 100dB (or just shy of 100dB and need that headroom for EQ), you're risking your hearing. I think a lot of people are far too cavalier with their hearing, especially when using headphones (I'm always amazed when I can hear someone else's music from ten feet away when they're using IEMs...) - we're headed for a generation of people suffering major hearing loss in their 50s and 60s as a result of unsafe listening practices.

It's all kind of moot anyway because that wasn't Amir's primary concern with these headphones - the absolute mess that is the frequency response of these cans above 1kHz is much more of a problem than the fact that they can't exceed deafening volume levels.