CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS
Lobby => Headphone, IEM, and Other Audio Related Discussion => Topic started by: Marvey on January 10, 2013, 04:28:59 AM
-
Finally got my setup for the HE500 tonight. Been meaning to do this for a long time - just soldered together the adapter cable.
- Dynamic
- Spacious
- Vice like control of the bass
- Neutral
- Very involving!
CD player -> Modified Behringer DCX2496 -> Schiit Mjolnir (Preamp) -> Crest CA2 (Power Amp) -> HE-500.
- The Mjolnir is an awesome preamp. The few shortcomings which were mentioned (dogmatically vigilant, lack of depth in stage) while driving headphones were not noted at all. It sounds cleaner driving the amp than driving the headphones directly, despite 20 feet of XLR patch cord. The beauty of balanced drive! I would presume that driving the power amp is a much easier load than driving headphones. The HE-500 sounds extremely open and spacious from the Crest CA2 (it's a characteristic of the amp.)
- Don't laugh at the Crest CA2. While most pro amps are shit, the Crest CA series is very good. There's a reason why it isn't $299 at Musicians Friend. (It use to cost MUCH less than it does now, just a few years ago.) It will kick the ass of the majority of so called audiophile amplifiers. I actually called around the Bay Area (when I lived there) various venues to ask a few professionals what amps they liked and felt were the best. Most of these sound reinforcement systems are active systems, and I noted that the CA2 was used a lot for tweeter applications (at least at the good venues). That told me something. Besides, I've gone through a few audiophile brand power amps, and the CA2s (I own several of them) have managed to stay.
- What I like about pro amps is that you can usually select gain and attenuation. Gain has been reduced from x40 to x20 via a DIP inside the amp. The attention at the front panel is rather nice for headphone use.
- I've always felt orthos needed massive power (and good quality power) to shine. Particularly with control of the driver. I've never heard the HE-500 sound so tight in the bass. The Mjolnir and Dynahi do a great job, but this is on a another level. No more blurry or muddy bass.
- The HE-500 isn't all that resolving, so adding extra stages did not seem to impact plankton retrieval. It should be noted that the modded DCX2496 is nowhere near the PWD2 though.
- Note minor EQ on DCX2496 to level off the 10kHz peak. The settings have since been adjusted to 10.1kHz -2.5db with a Q of 4. A combination EQ/DAC is awesome. I've noted the HiFiMan's tend to respond very well to EQ.
- Don't go out and buy any random power amp thinking you will get the same results. I've heard plenty of crappy sound from high powered amps / receivers driving headphones.
-
Love this rig. If I still had my HE6, I would have picked up that Crest amp for sure. There's one on ebay for $250.
I fed the HE6 7 watts @ its 50 ohm rating and though it sounded good, I thought there was probably more to be had.
Those cooling fans look noisy though...
-
Before the neo-orthos a lot of people in the ortho thread AFAIK, used to say that orthos were an easy load for amps to drive because they're dipoles I think. Maybe dBel can chime in. I remember Wualta mentioning it a few times, though I don't want to put words in his mouth.
Maybe they need a lot of certain kinds of power?
I'm just curious, I've always wondered how to reconcile the differing opinions on this one.
-
Love this rig. If I still had my HE6, I would have picked up that Crest amp for sure. There's one on ebay for $250.
I fed the HE6 7 watts @ its 50 ohm rating and though it sounded good, I thought there was probably more to be had.
Those cooling fans look noisy though...
Downside to pro-amps = cooling fans. I replaced the stock cooling fans with a similar model running at lower RPM :-) You can do this if you are running pro amps at home!
With this setup, I could compare between the Mjolnir output and CA2 output. I much preferred the CA2 output, at least with this headphone. At least we know the Mjolnir is a very good preamp.
The modern orthos need a ton of current. I don't know anything about the old ones.
-
I had intentions to do something like this with the HE-6, but couldn't stand them long enough to try.
-
Neither could I
-
Before the neo-orthos a lot of people in the ortho thread AFAIK, used to say that orthos were an easy load for amps to drive because they're dipoles I think.
Orthos were considered an easy load for amplifiers because their load is almost entirely 'resistive' (constant impedance at all frequencies) unlike the dynamic drivers.It was assumed that since the orthos didn't have any change in impedance with the frequency so they won't be generating any back EMF( so no electrical dampng) & the amps would find it much easier to drive.
This ofc has nothing to do with the power/current requirements of the driver. That has to do with the very low impedance/low sensitivity of neo-orthos which means that they would require huge amounts of currently to be driven adequately.(It still doesn't explain the need for gazillion watts power amplifiers though.)
-
:)p5
-
It still doesn't explain the need for gazillion watts power amplifiers though.
That part is very easily explained though.
Speaker amps are designed to deliver in 4 to 8 Ohms and mostly rated (to give highest figures) in Watts at the lowest impedance.
Ortho's are generally between 32 and 50 Ohm.
Simple calc says 100W into 4 Ohm = 20V
20V over 50 Ohm = 8W
So you need a 100W speaker amp to feed a 50 ohm ortho with 8W
The amplifier in that case is not delivering 100W but simply 8W
The current is NO problemo for any power amp.
It is for most headphone amps.
Just like delivering the voltage is no problem for most speaker amps (depends on the power rating)
It is for most headphone amps that in general do not exceed 10V output voltages under 50 Ohm loads (2W)
-
^Ya but shouldn't 8W be an overkill even for hifiman orthos?
-
Maybe the coarse traces on the large HiFiMan diaphragms require a steady stream of more tightly packed electrons.
-
^Ya but shouldn't 8W be an overkill even for hifiman orthos?
I think so looking at the SPL and inevitable compression at those powers ;)
Short peaks however with average powers of about 10dB lower (0.8W) will give it great and realistic dynamics.
I still have to build myself a peak meter (was in the pipeline) to 'see' the shortest of peaks an d how big they are.
-
Why I would like explore is why the increase in precision and control? Will need to try other headphones to see if the react similarly.
-
^ Would it be possible for you to run your distortion measurements out of this rig ?
-
I would love to see measurements for this too.
Also interested if an Audeze phone can get a great synergy like this as well.
-
LOL, you guys are thinking exactly the same thing I was when I on my way to visit a client this morning. Just got to get off my ass and haul either the PC / test rig downstairs, or power amp / preamp upstairs. Hmmm, that's an easy decision.
I will have to do it in the middle of the night...
-
Also interested if an Audeze phone can get a great synergy like this as well.
Yes, the best I ever heard the LCD2 r.1 was on my old Sansui. It grabbed that driver by ballz even w/ high output z.
I'll bring over my HE5 to play w/ the CA2.
-
Any real reason to keep the preamp in this setup?
-
Volume control. Probably not a good idea to use passive volume control in this case b/c I'm taking the signal from the DAC directly from the chips without an active buffer stage (part of the mods). DCX2496 has digital volume control, but it's limited to -15db.
-
On the tangent of easy or difficult loads, the perspective from speaker amps and speakers is this:
As guru implied, the impedance of orthos tends to be more even throughout the frequency range. Take BG NeoCD planar drivers. A flat 4 ohms from 20Hz to 20kHz. Whereas with traditional dynamic drivers (especially in multi-way configuration with crossovers) can tend to have really screwy impedance with some spots at nominal rated 8 ohms, a rising impedance to 16 ohms or more in the treble, and on occasion even some dips way down to 2 ohms (getting closer to a short circuit).
Amps don't like driving things which are near a short circuit. Such amps do exist, but I believe they are called arc-welders, and are probably not suited for reproducing audio frequencies. Another important reason is that transducer systems which have screwy impedance will have FR irregularities depending upon output impedance of the amp. This is rarely a problem with solid-state systems with large amount of feedback = very low, almost 0 output impedance. Tube amps however will have a more difficult time.
Now going back to the case of multi-way dynamic speaker systems. It is indeed possible to flatten the impedance curve of such systems through use of passive components, i.e. caps, coils, resistors, etc. The downside to this approach, is that these components, while they make the speaker more palatable to amps, also act as heat-sinks essentially wasting energy output from the amp. Some designers elect to implement these impedance compensation circuits, others elect to leave them out (and assume you have a super duper mega power amp which be double as a welder.)
At any rate, orthos are different in that they tend to have lowish impedance, but poor efficiency. I would not say orthos are an easy load to drive compared to Grados / ATs (extremely efficient, low impedance) or Senns (moderately efficient, high impedance).
More thoughts later.
-
So the question is, lets do a relative comparison between the HD800 and HE-500. We'll simplify things for now.
HD800
Nominal impedance: 350 ohms (doubling around ~100Hz)
Power required for 90db SPL: 0.00016 watts
HE-500
Nominal impedance: 46 ohms
Power required for 90db SPL: 0.00204 watts
The amplification question
Most people who own HD800s would agree that some sort of amp with decent power is necessary to get the best of out them in terms of bass precision, control, slam, etc. So lets take for example the BHA-1, EC S7, Mjolnir or even the BA (not as powerful as people think). These three amps will output approximately 300mW to 800mW to the HD800.
HD800 amp power / 90db sensitivity ratio
So let's do 90db sensitivity thing and come up with a ratio. For the sake of simplicity, let's pick a number and use 500 mW for the output of a typical HD800 amp in a "good" setup:
0.500 W / 0.00016 = 3125 x
HE-500 amp power / 90db sensitivity ratio
So let's say we are using a speaker amp which outputs about 8 watts into 46 ohms (again, keeping in mind that 46 ohms is much much higher than most speakers which are nominal 8 or 4 ohms, hence less power into headphones).
8 W / 0.00204 = 3921 x
---
The mega power amp paired with the HE-500 has a higher power / headphone sensitivity ratio, but it's not any more overkill than many amps commonly paired with the HD800. We are still playing within the same magnitude.
-
Let's extend the study with the usual dB's instead of factors of power (some may prefer dB over factors).
HD800 (350 Ohm) needs 0.16mW for 90dB SPL (0.235V), driven to 500mW will require 13.2Veff and only draws a 0.04A current
with 500mW you will end up (if the HD800 would behave linear which it probably doesn't at these levels) with 125dB SPL
This output voltage is equal to a 45W into 4 Ohm power amplifier which thus could also be used instead of a headphone amp without any output resistors added.
HE-500 (46 Ohm) needs 2.04mW for 90dB SPL (0.306V), driven to 8W will require 19Veff and draws 0.4A of current.
with 8W you will end up with 126dB SPL
This output voltage is equal to a 90W into 4 Ohm power amplifier which thus could also be used instead of a headphone amp without any output resistors added.
So equally loud yet the HE500 is 16x as inefficient.
Let's hope that target SPL are merely extremely short peaks in very dynamic music ... for our ears' sakes.
-
Thanks for doing that Purrin! I want to hear my orthos on a power amp now!
-
When do I get to hear this beauty of a system? p:3
-
Anytime. I'm in all week. Need to give you Frogbeats back.
-
Anytime. I'm in all week. Need to give you Frogbeats back.
Let me know what your preferred time is after 6pm Monday - Friday. :)
-
Tonight should work.
-
Whoa, must have missed this thread... I have a Crest CA-2 in the basement I kid you not, I'm going to drag it up and give it a spin with my orthos..
-
Tonight should work.
See you tonight. ;D
-
Thanks for doing that Purrin! I want to hear my orthos on a power amp now!
Just thinking out loud (hoping someone will catch my mistakes for add stuff.)
@Solderdude: Thanks for putting in db / log terms - which is more appropriate since we hear that way.
Whoa, must have missed this thread... I have a Crest CA-2 in the basement I kid you not, I'm going to drag it up and give it a spin with my orthos..
WTH? Do we have a Crest CA-2 club now? :-\
-
It's not a real club until we start willfully excluding people.
-
Stopped by to listen to this system....
The Synergistic system is synergistic. p:3
SERIOUSLY.
-
I clearly do not roam the threads enough , this is a great reflection on the poweramp for ortho phenomenon. LFF - you should try and run the XA1 directly. If it sounds even more phenomenal, then it is time to remove the voltage divider on the headphone output.
never heard of crest amps before either.
..dB
-
The Crest stuff is pro / sound reinforcement gear (among QSC, Crown, etc.)
I figured it was time I posted something specific on this since no one on HF could ever explain why these HFM orthos sounded better from power amps other than they sounded "better" without any qualifications. The observations here (less one-note/blurry/muddy bass - more articulate, more open and spacious) only pertain to the HE-500 of course.
-
Not surprised at your finding. This was my conclusion too and used to listen straight out of the Sansui AU-217 and tried it once with the Plinius SA-100mk2. ANd i ran it without the voltage divider both times. Mostly with Wharfedale ID1s and Fostex T50RP
-
Hi guys!
I am a newbie here. LFF know me just enough through a pm exchange to introduce me to this thread. Nice forum BTW.
If I may chip in on your power amp discussion, I would like to think out loud for a moment. Let start with dynamic headphones. To generate the attack of a big bass sound wave, the membrane first have to move torward its max amplitude, driven by an electric field. We know that the force of the electro field is proportional to the current.
This sound wave, lets call it a sin wave, is a moving train and the membrane has to accelerate fast if it want to get on it. In real life, there is always a very little lag because of the inertia of the membrane. It cannot get instantaneously at the proper speed. The higher the current, the faster the membrane will get to the imposed speed (or the lighter the membrane, or the more powerfull the natural magnet is).
Then it gets only worse. Just as it reach it's max point of displacement (top of the sin wave), the electro magnet reverse its energy, trying to impose a change of direction to the membrane (lets not go into the hysteresis of the field here). But with the acquired momentum, the membrane will fight this force field and move a little too far before it finally come to a stop and reverse its movement (generating, like a dynamo, a counter current that will fight the "pure" signal). Again, the higher the current, the faster the membrane will reverse (or the lighter the membrane, or the more...).
In real life, the displacement of the membrane doesn't follow perfectly the sound wave. So you not only need your tension to align with your impedance (non linear through the spectrum, oh god) and your power to move some air and play it loud. You also need current to control your membrane behaviour. Making it follow the sound wave as close as you can. The lower the frequency, the more energy is in it, the more difficult it is to control/impose/restrain the movement the membrane by its own initiative! Or in other words, if the current is just enough to move the membrane, it won't be able to stop it fast enough. So high impedance headphone on too small amplifier eat the tension and offer less current to control your membrane, not only lowering the volume, but more importantly damaging the sound.
To makes things a bit more interesting, we could add that the membrane has a non linear elasticity. Of course, there is no perfect amplifier either. They all do have their own quirks. An ample reserve of fast power supply will help the amplifier to cope with any scenario of fast attack, generating instantaneously the power it needs to control these lazy and errant membranes (which relate to speed, control and sharpness, a purer wave).
How does everything apply to orthos? Well, in fact, I don't know much about this technology. I only suspect that the membrane has a low inertia and it should be easier to control them. And its lower impedance doesn't take so much tension. So the culprid must be its low sensitivity that eat lots of power/current to produce a loud enough performance. This means probably too low current to adequately control/impose/restrain of the membrane on a smaller amplifier. Only a guess here.
Does this all make sence?
-
Welcome to the forum girly stephanie..
The damping factor thing has been discussed here and there already.
For headphones above .. say 32 Ohm... it really doesn't matter that much if a driver is driven from a 0.001 Ohm power amplifier or 0.1 Ohm headphone amplifier.
It DOES when driven from an amplifier with a considerable higher output R ;)
You see, the damping current is determined by the impedance of the driver, not by the output R of the amp as the latter is relatively too small and they are always in series for current but in parallel for voltage to make it more complicated.
The perceived 'grip' on the driver is perhaps just perceived that way or caused by voltage division FR changes.
Also note that a headphone membrane has no problems following a bass note's speed but most dynamic headphones DO have an increased impedance at those frequencies which are caused by the 'overshoot' or back EMF. Electrical damping doesn't do much though.
The toughest thing to follow are the higher frequencies.
The speed at which the membrane travels is many factors higher at 5kHz than at 50 Hz (you can do the math) yet 5kHz and even 10kHz isn't a real problem to follow.
5kHz is about the highest harmonic content of a bass and it should be noted that the amplitude there is extremely small already.
http://www.independentrecording.net/irn/resources/freqchart/main_display.htm
If it would be that problematic you would see a different impedance plots of the headphone when driven from different source resistances which is not the case.
The HEARD differences are caused by voltage division IF the output resistance is relatively big opposite the impedance and depending on the mechanical properties of the driver.
The reason the bass performance is always 'the culprit' and not have enough slam or power can (mostly) be contributed to 2 things.
Amplitude difference (due to volume control change after changing something) because of our nature of hearing (Fletcher/Munson curves say you hear relatively more lows at increased volume) and the most important factor the changes in FR at the 'bass' fundamental frequencies opposite the relatively less boosted harmonics of those bass notes resulting in a different 'bass'
An ortho's efficiency is relatively bad (little windings, relatively large airgap) and so you need heaps of power to motivate it to move.
In the other direction a motion of the membrane induces little if no current in the membrane for the same reason.... flat impedance graph.
Damping theories and 'grip on the driver' can go overboard, there isn't any grip on the membrane.
Why a power amp sounds 'better' with orthos ?... because there is more voltage and current available and thus MUCH more dynamic headroom.
Voltage isn't a real problem for desktop amps, current is often limited though.
No such limits, for headphones, exist using power amps as they are designed to deliver 10 times more current than an ortho can ever draw before bursting into flames.
The below mentioned Plinius SA-100mk2 would in fact be able to pump 20W into a T50RP which (if it were linear) would result in 141dB (if it would have survived being only 3W).
So you simply have loads of dynamic range and the noise floor of the power amp isn't bothering us due to the low efficiency of the driver.
The noise remains below the audible treshold.
More sensitive headphones connected directly to a power amp (600 Ohm headphones can be connected to power amps without any resistors) might have audible noise in the background as power amplifiers can easily have higher voltage noise levels without being audible (unless our ears are close to the tweeter).
About the non-linear behavior of an electro-mechanical transducer that is most definitely a grave point.
Ruthlessly shown in Purrins measurements of the HE500 which showed the distortion is the same regardless of the amp (Magni-O2) and many factors higher than the addition of the amplifiers when using testtones.
Would be great to repeat the test with white noise and a spectrum analyser in that case the objections of single tones not revealing everything would be smaller, yet still not be the more organized audio spectrum of music.
So much tests to run but even more music to enjoy.
Though choice ... to measure or enjoy music... :-Z
In the end... an ortho fed from a power amp makes sense and has been making sense for a long time already.
-
This is a great discussion. I always wonder if more power is truly better. In terms of dynamic headroom:
If I have a modest amp that can do 500mw into HE-500 46ohms, that provides 116db peaks at the HE-500 89dB/mW. 89 + 10 × Log(500) = 116db.
Those peaks are pretty loud. Assuming I have a much more powerful amp like the 8W example, and given everything else being equal (low amp output impedance, etc), there should theoretically be zero difference in what I hear as long as my peaks don't go over 116 causing the amp to clip.
Is this right or am I missing something fundamental? It seems an amp that can put 500mw vs 8W into the same load isn't an advantage even on the HE-500 in most circumstances. It'll only make a difference if you want those peaks to be over 116db without clipping (current limiting), a volume that is probably not typical for most long term listening.
-
Why does everything have to be a function of loudness? Is SPL that attractive of a red herring? Are we all 17 year olds w/ arrays of 12 inch subwoofers in the back of our Hondas?
-
This is a great discussion. I always wonder if more power is truly better. In terms of dynamic headroom:
If I have a modest amp that can do 500mw into HE-500 46ohms, that provides 116db peaks at the HE-500 89dB/mW. 89 + 10 × Log(500) = 116db.
Those peaks are pretty loud. Assuming I have a much more powerful amp like the 8W example, and given everything else being equal (low amp output impedance, etc), there should theoretically be zero difference in what I hear as long as my peaks don't go over 116 causing the amp to clip.
Is this right or am I missing something fundamental? It seems an amp that can put 500mw vs 8W into the same load isn't an advantage even on the HE-500 in most circumstances. It'll only make a difference if you want those peaks to be over 116db without clipping (current limiting), a volume that is probably not typical for most long term listening.
I am inclined to fully agree with you, and am sure Voldemort will too.
However, Not all amps that are measured with an output of 1kHz frequency and reach a certain output level (often with only 1 channel driven to get better numbers) have the same power bandwidth with both channels driven with wide spectrum signals.
Consider the provided power in squarewave and sine wave with the same peak voltage needs different power amounts of power.
Reality is somewhere in between (leaning towards sinewave.. agreed).
Also it will depend on the dynamics of the song.
If you playback a highly loudness war'ed song you will be looking at 110dB average SPL and 116dB peak.
This would have let you turn down the volume knob MUCH sooner and the 0.5W is dynamic and powerful enough !
Now a classical piece with average SPL of say 90dB that is played back at realistic levels small peaks might occur of over 116dB which are NOT found to be absurdly loud but when compressed takes away a bit of the enjoyment.
I think it is too bad no-one has powermeters on their amps, I am still contemplating making an ultra-fast one that can measure even the shortest peak just to see if I am nearing the clipping level.
Also one could easily shout 'expectation bias' but I don't want to cause I was not there and did not meet the persons doing the test.
Some individuals I don't 'believe' others I give the benefit of the doubt.
8W (or even 20W in the other example) may seem a bit too much, for drivers that are rated at 3W, but the rating is for continuous sinewave and is a power it should handle without burning or permanent damage. For music signals the average power is lower so when 3W average power is reached 20W peaks may occur (8dB between peak and average power) which it could handle without any probs.
Consider our hearing has built in AGC (Automatic Gain Control) and has problems with dynamic ranges over 70dB this means you will be needing more power during the day to get the same sense of 'loudness' as in the wee hours where you can hear your watch tick.
-
Thanks for a very good reply. I totally agree with you, on very dynamic music (classical, etc) you may hit very high peaks briefly and not know it because the average volume is much much lower. Yes it'd be great if amps had a peak current meter so we can know roughly how much headroom we really need.
I have a HE-500 and wonder if it'd sound better with a much more powerful amp, and if it does sounds better if that's due to power or some other reason. I don't listen to my music crazy loud, nor do I listen to extremely dynamic classical so I'd think 116db peaks is definitely enough. That makes me think 500mw of power into the HE-500 is enough (for me). Perhaps I can get SQ gains still, but not necessarily due to more power..
-
BTW, Anaxilus came over and we tried the same thing with the HE-5. The HE-5 sounded better from the power amp as well. More open, dynamic, and most of all, better clarity and control in the bass.
-
Have you tried a T50rp?
-
Hmmm, not yet.
-
Maybe it can turn rubber into mila kunis' butt?
-
Sadly, the HE5 needs even more juice than the HE500.
-
The HE-5 is rated at 87db/mW sensitivity so you still only need 0.8W to hit 116db peaks. So unless you're hitting peaks beyond that in dynamics while listening it's not power that is giving it better sound, but something else with the amp that's still a mystery..
Only a real peak current meter will tell you how much of that 8W power you are really 'using'..
-
In this case it was a matter of the HE5 needing more gain than the HE500 for the same output.
Btw, the HE500 is 38ohms/89dB, not 46ohms. http://hifiman.us/Products/?pid=102 (http://hifiman.us/Products/?pid=102)
-
In this case it was a matter of the HE5 needing more gain than the HE500 for the same output.
Btw, the HE500 is 38ohms/89dB, not 46ohms. http://hifiman.us/Products/?pid=102 (http://hifiman.us/Products/?pid=102)
The HE500 is spec'd as being 38 Ohm.
It is probably an average value as Jerg measured one driver to be 33 Ohm and the other 46 Ohm so there seems to be quite some spread even in 1 headphone.
The 46 Ohm I 'took' from impedance measurements I trust over claims of manufacturers (namely Tyll's HE500 measurements) and should have typed 47 Ohm b.t.w.
There is a good chance though of people having HE500's close to 38 Ohm.
On the same output VOLTAGE an HE500 is only 1.7dB 'louder' than an HE5 eventhough the efficiency of the HE5 is 3.7dB lower (in POWER) assuming Tyll's measurements were correct.
IMO it makes sense to drive ortho's from a power amp, just like you can easily drive 600 Ohm headphones directly from power amps (it's what they were designed for back in the days)
-
I've measured many HE-500s out of curiosity and the ones I personally measured ranged between 33ohm - 46ohm so the 38ohm is definitely an average and not all samples will measure that..
-
I've measured many HE-500s out of curiosity and the ones I personally measured ranged between 33ohm - 46ohm so the 38ohm is definitely an average and not all samples will measure that..
Are a lot of them wildly off between the two channels, as in 33Ohm Left, 46Ohm right? Because that is what is up with my pair haha. I don't notice any effect in practice though.
-
Maybe it can turn rubber into mila kunis' butt?
I rather have her face...but I'll try to bring over a T50RP soon to test out.
-
Are a lot of them wildly off between the two channels, as in 33Ohm Left, 46Ohm right? Because that is what is up with my pair haha. I don't notice any effect in practice though.
One pair I measured was ~36 both channels. The existing pair I have is ~45 both channels. The good thing is that both headphones had essentially the same sensitivity and FR as each other. At least I think so. I will check.
-
The one Golden Ears tested was 37 Ohm, the one tested by a Russian site was 33.8 Ohm (both channels)
-
My first pair's right cup was roughly 20% louder than its left (since I was using Windows to correct it for awhile before returning them). No idea what that would translate to in impedance difference, but I'm assuming that was the cause. Shame because that pair sounded better than my current one after volume adjustments.
-
My first pair's right cup was roughly 20% louder than its left (since I was using Windows to correct it for awhile before returning them). No idea what that would translate to in impedance difference, but I'm assuming that was the cause. Shame because that pair sounded better than my current one after volume adjustments.
That assumption is discrepant with my observations with my pair though; 32-48 Ohm Left vs Right impedance, and no channel imbalance at all. It would have been great (well, not for you but for the general knowledge about planar magnetic cans) if you also measured the impedance of the imbalanced pair you had, and they turned out to match. That would have shown that balance/FR is not directly related to the apparent impedance values. Ah well.
Looking forward to Purrin's low vs high impedance HE500 measurements.
-
Are a lot of them wildly off between the two channels, as in 33Ohm Left, 46Ohm right? Because that is what is up with my pair haha. I don't notice any effect in practice though.
One pair I measured was ~36 both channels. The existing pair I have is ~45 both channels. The good thing is that both headphones had essentially the same sensitivity and FR as each other. At least I think so. I will check.
This would be very interesting. There have been a few posts with people listening to different impedance HE-500 and claiming they hear a difference in FR. I have noticed myself the 33ohm unit bass FR was a bit different than the 45ohm unit (33ohm had a bit less bass, about 1.5db difference on the low end, not very noticeable except in fast direct comparison, could tell in blind test, also had slightly brighter treble). Not sure if this is due to just random unit variance or actually correlated to the driver impedance. The difference was very very small but it was there..
-
Are a lot of them wildly off between the two channels, as in 33Ohm Left, 46Ohm right? Because that is what is up with my pair haha. I don't notice any effect in practice though.
One pair I measured was ~36 both channels. The existing pair I have is ~45 both channels. The good thing is that both headphones had essentially the same sensitivity and FR as each other. At least I think so. I will check.
This would be very interesting. There have been a few posts with people listening to different impedance HE-500 and claiming they hear a difference in FR. I have noticed myself the 33ohm unit bass FR was a bit different than the 45ohm unit (33ohm had a bit less bass, about 1.5db difference on the low end, not very noticeable except in fast direct comparison, could tell in blind test, also had slightly brighter treble). Not sure if this is due to just random unit variance or actually correlated to the driver impedance. The difference was very very small but it was there..
I dunno, if purrin ends up proving that impedance actually has no relevance with the FR and channel balance in general, then I'd be a happy camper because I won't always be bugged that my L and R channels are a whopping 13 Ohm apart in impedance.