HD600 Safety and Quality via iPhone

[WickedInsignia]

Hey all! Apologies in advance if this comes off as a cringey/newbie post but I simply can’t find the info I need elsewhere online.

I have a Sennheiser HD600 arriving soon and I intend to drive it through an iPhone 6. I understand 300 ohms is pushing the limits of the onboard amp, but I enjoyed the sound solely through my phone at the store and found I only turned volume up halfway to reach my preferred listening level.
Using the HD600 through my iPhone is optimal for my listening situation and I’d like to avoid the use of an amp due to desk space.

I have a few questions regarding this situation that I’d like answered to ensure I’m making the most of my investment:
- I’ve heard that clipping can potentially damage a driver. Would driving it through an iPhone produce clipping or any other artefacts that may cause damage?
- Am I to believe an amp will increase the quality of audio through the HD600? How discernible is this in reality?
- I have a Focusrite Scarlett Solo Gen3. The company expresses it can drive headphones up to 200 ohms and maybe more....would this be enough to get good performance from the HD600 if the iPhone really doesn’t deliver?

Thanks for your attention and time on this topic! I’m not very technically inclined in amping/drivability and look forward to some opinions from those who know what they’re talking about haha.

 

[Jimbob54]

Hey all! Apologies in advance if this comes off as a cringey/newbie post but I simply can’t find the info I need elsewhere online.

I have a Sennheiser HD600 arriving soon and I intend to drive it through an iPhone 6. I understand 300 ohms is pushing the limits of the onboard amp, but I enjoyed the sound solely through my phone at the store and found I only turned volume up halfway to reach my preferred listening level.
Using the HD600 through my iPhone is optimal for my listening situation and I’d like to avoid the use of an amp due to desk space.

I have a few questions regarding this situation that I’d like answered to ensure I’m making the most of my investment:
- I’ve heard that clipping can potentially damage a driver. Would driving it through an iPhone produce clipping or any other artefacts that may cause damage?
- Am I to believe an amp will increase the quality of audio through the HD600? How discernible is this in reality?
- I have a Focusrite Scarlett Solo Gen3. The company expresses it can drive headphones up to 200 ohms and maybe more....would this be enough to get good performance from the HD600 if the iPhone really doesn’t deliver?

Thanks for your attention and time on this topic! I’m not very technically inclined in amping/drivability and look forward to some opinions from those who know what they’re talking about haha.

If you were loud enough and it sounded good at half volume, you won't clip the iPhone amp and definitely not the drivers at that level

A bigger amp would only increase the quality if you were at levels that caused the iPhone to distort or clip

Some comments on the focus rite https://www.audiosciencereview.com/...yet-good-unit-or-is-it-a-pass.3854/post-91733

Not sure if it would add much to the iPhone, but worth testing with both, can't hurt.

 

[WickedInsignia]

ot sure if it would add much to the iPhone, but worth testing with both, can't hurt

Absolutely! I intend to test both when it finally arrives....although of course some expectation bias may contribute. My impressions will unfortunately be subjective in that case but I will relay them here anyway.

I’ll have a read through that material, thank you!

 

[hyperplanar]

There seems to be a pervasive misunderstanding about how higher impedance (ohm) headphones are hard to drive. This is a true statement, but not in the way that many seem to think.

The higher the impedance of the load (headphones), the less current is allowed to flow compared to a lower impedance load at the same voltage (which to simplify, voltage is what a volume knob on an amplifier or the volume setting on your iPhone sets).

The sound your headphones produce is a result of power, which is the product of voltage times current. Since less current can flow, more voltage is needed to produce the same power as with lower impedance headphones. At every equivalent voltage, the amplifier is actually working less hard than with lower impedance headphones, because it doesn’t have to output as much current. The extreme end of this is when the load impedance is extremely high, such as a line-in/audio input on an amplifier, etc. where the load impedance could be something like 10,000 ohms. So I think it would be fair to say that as the load impedance goes up, it actually becomes an easier load to drive by the source, because less “oomph” is needed behind that voltage.

The problem with using an iPhone’s headphone jack with an HD600 shouldn’t be that it will overload the internal amplifier causing damage/distortion, but that its max voltage is not high enough to drive the HD600 to satisfactory loudness levels.

 

[WickedInsignia]

The problem with using an iPhone’s headphone jack with an HD600 shouldn’t be that it will overload the internal amplifier causing damage/distortion, but that its max voltage is not high enough to drive the HD600 to satisfactory loudness levels.

I must be a fairly low-SPL listener by all standards because I found the volume level perfectly acceptable for my preferences at around half of what the iPhone could push. I get what you mean though, and that's all very helpful!!

In that case, am I to understand the iPhone 6 is perfectly capable of driving the HD600 to its best performance at any chosen volume? There's generally a lot of talk on the net about the HD600 being "scalable", or sounding better at the same listening level as more power is supplied to it via "better" amps. Should I assume that if sound is being created by the headphone and the DAC is of good quality (such as that in the iPhone) the objective sound quality will not improve with sources that have much more volume headroom?

 

[WickedInsignia]

A bigger amp would only increase the quality if you were at levels that caused the iPhone to distort or clip

Ah okay, this is quite informative and I didn't give it proper thought the first time around.
So I guess if there is no audible distortion, the headphone is performing at its best regardless of source? TBH I would not know what to look for to determine if there was any sort of distortion or clipping.

 

[Jimbob54]

Ah okay, this is quite informative and I didn't give it proper thought the first time around.
So I guess if there is no audible distortion, the headphone is performing at its best regardless of source? TBH I would not know what to look for to determine if there was any sort of distortion or clipping.

Not quite that simple, but let's go with that. I tend to find I increase volume during a listening session so you might end up at the top end of the iPhone volume after a time.

As others have said, if you find yourself wanting a bit more ooomph, then you might want to get a more powerful amp down the line. But volume preferences seem to vary wildly around here and can be content dependant too of course. A classical listener might need more absolute headroom, for example.

I wouldn't worry about it tbh, get them and worry about an extra amp only if you ever find the iPhone to be insufficient. A different amp is unlikely to give different sound at the same output levels you listen at.

 

[Doodski]

Not quite that simple, but let's go with that. I tend to find I increase volume during a listening session so you might end up at the top end of the iPhone volume after a time.

As others have said, if you find yourself wanting a bit more ooomph, then you might want to get a more powerful amp down the line. But volume preferences seem to vary wildly around here and can be content dependant too of course. A classical listener might need more absolute headroom, for example.

I wouldn't worry about it tbh, get them and worry about an extra amp only if you ever find the iPhone to be insufficient. A different amp is unlikely to give different sound at the same output levels you listen at.

Ima tightening my Sennheisers right now for more OOMph! Content dependant...

 

[WickedInsignia]

Not quite that simple, but let's go with that.

I understand (I think) that music with higher dynamic range (such as classical) will need more volume by nature and that distortion would most likely appear in those situations due to spikes from crescendos and other peaks, but fortunately my choice of music tends to be fairly compressed.

Good to hear that I could be getting the most out of my headphones from the iPhone (at least in my particular case)! I'll be sure to do some listening tests vs the Focusrite regardless and leave my impressions here.

It was so difficult to get objective information on this haha. I was led to believe something like the iPhone couldn't push the HD600's drivers fast enough, to emit tight enough bass or something of the sort, and that higher-powered amps would somehow improve the performance of the drivers at low listening levels.

 

[solderdude]

In that case, am I to understand the iPhone 6 is perfectly capable of driving the HD600 to its best performance at any chosen volume? There's generally a lot of talk on the net about the HD600 being "scalable", or sounding better at the same listening level as more power is supplied to it via "better" amps.
Should I assume that if sound is being created by the headphone and the DAC is of good quality (such as that in the iPhone) the objective sound quality will not improve with sources that have much more volume headroom?

No the iphone is not capable of driving the HD600 at any chosen volume. It is limited to a certain volume level.
Up to the max level the iphone can reach it will sound exactly the same as from an amp. Even if that one can reach several Watt.
Only when you want to go beyond the levels that can be reached with the iphone the amp will sound better (by lack of clipping) and it can then reach impressive levels and with the needed bass boost becomes a very impressive headphone. That is the 'scaling' part.

As long as you keep the volume at polite levels you don't need and won't benefit from any amp.

 

[WickedInsignia]

Ima tightening my Sennheisers right now for more OOMph! Content dependant...

I'm sure once I've worn my ears down with too much EDM I'll find myself in a similar boat!

 

[WickedInsignia]

No the iphone is not capable of driving the HD600 at any chosen volume. It is limited to a certain volume level.

Oh of course, I meant within the limits of the iPhone's maximum volume. Since half of what the iPhone could push out is enough for my ears, I don't really have intentions to go past that.

Up to the max level the iphone can reach it will sound exactly the same as from an amp. Even if that one can reach several Watt.

That's the exact information I was looking for! Glad to hear that's the case, and that there's nothing "missing" from the HD600 picture if I listen at levels within the iPhone's limits (I hope that's the right conclusion to make from that?)

Also, I gotta say DIY Audio Heaven has been a fantastic resource for me. Sincerest of thanks for the effort you put into that site and your impressions, they've helped me on my audio journey immensely.

 

[Jimbob54]

Ima tightening my Sennheisers right now for more OOMph! Content dependant...

OOMph

 

[Leporello]

I must be a fairly low-SPL listener by all standards because I found the volume level perfectly acceptable for my preferences at around half of what the iPhone could push. I get what you mean though, and that's all very helpful!!

In that case, am I to understand the iPhone 6 is perfectly capable of driving the HD600 to its best performance at any chosen volume? There's generally a lot of talk on the net about the HD600 being "scalable", or sounding better at the same listening level as more power is supplied to it via "better" amps. Should I assume that if sound is being created by the headphone and the DAC is of good quality (such as that in the iPhone) the objective sound quality will not improve with sources that have much more volume headroom?

I have Iphone 6s and the HD600. Spotify loudness level set as 'Normal'. On most recordings the max volume level of the Iphone is more than enough. I never listen to any music that loud. I am not sure about the sound quality. The headphone out of an old Benchmark DAC1 might sound slightly punchier or brilliant but then again this could be placebo doing its thing.

The HD600 is just a headphone. It is not any more "scalable" than other headphones out there. "Scalability" is just a myth perpetuated in the Head-Fi fantasy universe.

 

[WickedInsignia]

The HD600 is just a headphone. It is not any more "scalable" than other headphones out there. "Scalability" is just a myth perpetuated in the Head-Fi fantasy universe.

Unfortunately that's the world I'm escaping from. The audiophool dimension corrupts everything deeply and darkly. Suddenly what's technical truth and subjective bullshit merges into an ambiguous sludge and next thing you know you're part of the hive!

 

[AnalogSteph]

To be fair, HD600/650 are among the lowest-distortion 40 mm driver cans out there (even if not a match for planars and the like), so they make a decent basis for EQ and whatnot. You have to keep in mind that this notion of "scalability" is essentially as old as HD650s themselves, which were king of the hill for (remotely affordable) dynamic headphones when they came out in 2003. Few people were crazy enough to own anything as exotic and expensive as some Stax electrostats. Kilobuck dynamics were years away at this point, and planar magnetics were a funny niche technology that only Fostex used in mass-production cans most popular for band practice.

Looks like the iPhone 6 can output a maximum of almost exactly 1 Vrms into 150-330 ohm loads, with the volume obviously topping out before it has a chance to clip. For most people and all but the most dynamic material, it should generally go loud enough with HD600s. The worst that can happen is that it just doesn't and you find yourself wishing for more output with the volume maxed out.

 

[WickedInsignia]

To be fair, HD600/650 are among the lowest-distortion 40 mm driver cans out there (even if not a match for planars and the like), so they make a decent basis for EQ and whatnot. You have to keep in mind that this notion of "scalability" is essentially as old as HD650s themselves, which were king of the hill for (remotely affordable) dynamic headphones when they came out in 2003. Few people were crazy enough to own anything as exotic and expensive as some Stax electrostats. Kilobuck dynamics were years away at this point, and planar magnetics were a funny niche technology that only Fostex used in mass-production cans most popular for band practice.

Looks like the iPhone 6 can output a maximum of almost exactly 1 Vrms into 150-330 ohm loads, with the volume obviously topping out before it has a chance to clip. For most people and all but the most dynamic material, it should generally go loud enough with HD600s. The worst that can happen is that it just doesn't and you find yourself wishing for more output with the volume maxed out.

Enlightening and succinct! Thanks so much for the info, that certainly helps put my mind at ease around using the iPhone to drive these.

 

[3125b]

... unfortunately newer smartphones have lower output voltage, here are some that I measured (only power, not signal quality - they're all more or less fine in that regard):


What I can tell you from experience is, that my iPad Pro 9.7 (same chipset as the iPhone 6s, 1Vrms max) can drive even my Beyer T90 and AKG K601 just fine, both have a lower sensitivity and lower impedance than the HD600.
Unfortunately iOS doesn't seem to have a systemwide EQ, and Spotifys EQ is no more than a bad joke.

 

[hyperplanar]

... unfortunately newer smartphones have lower output voltage, here are some that I measured (only power, not signal quality - they're all more or less fine in that regard):
View attachment 116976

What I can tell you from experience is, that my iPad Pro 9.7 (same chipset as the iPhone 6s, 1Vrms max) can drive even my Beyer T90 and AKG K601 just fine, both have a lower sensitivity and lower impedance than the HD600.
Unfortunately iOS doesn't seem to have a systemwide EQ, and Spotifys EQ is no more than a bad joke.

I noticed you’re located in Germany, is this because of the EU regulations on max headphone listening level? As far as I’m aware the lightning to 3.5mm dongle here in the US still outputs 1 volt.

 

[Gadget Goober]

I'd like to add, and would love for the more experienced than I to jump in, for sake of clarification and education: I've heard some schools of thought that state that underpowered amps could actually damage drivers such as the higher impedance ones in your (I'm sure) beloved 6xx's - surprisingly, and not the other way around. I'm not qualified enough to argue against or for this, other than saying it makes sense: but the theory states that the clipping of the sine waves creates square waves, which can be difficult for your drivers to reproduce due to the sudden start and stop of the drivers. Please, I'm no expert, there's obviously much better persons here that may be able to support or deny this. I'm not sure if the modern phone amps have workarounds to this in some way. In fact, I'd love someone to jump in an educate me.

With that said, I've never had an issue, but my volume levels and "punch" on my 6xx were lacking. Your volume levels and "punch" may or may not be lacking - to you. But is there is no worry in damaging your iphone's circuitry. My HD6xx's are lacking in aural enjoyment dept. to my ears even on my Fiio M11 (22mw @ 300ohm I believe), which is why I built some balanced cables for the 6xx just to aid portable enjoyment. The increased power that the glorious Mr. Ohm lends even if voltage or current limited helps massively (for me!) to aid in enjoyable portable listening without an external amp.

Guess what I'm saying is that if it sounds good to you, you'll probably be okay... over the past 39 years I've never personally damaged any cans or equipment, even when being curious and stupid. But I'm no expert... at all.