## Topic: Sennheiser HD800: What type of amp do I need? (Read 17585 times)previous topic - next topic

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• skamp
• Developer
Sennheiser HD800: What type of amp do I need?
##### Reply #25 – 24 December, 2012, 07:14:51 AM
that amp has pretty high output voltage, but fairly crappy output impedance at ~ 34 ohms

Where did you get that figure? FiiO rates it at < 10?.
See my profile for measurements, tools and recommendations.

• saratoga
Sennheiser HD800: What type of amp do I need?
##### Reply #26 – 25 December, 2012, 02:08:20 AM
I would basically never trust the published specs, but if they're true that amp has pretty high output voltage, but fairly crappy output impedance at ~ 34 ohms.

Where did you get that figure?

As I said, those are the numbers GSARider quoted from Fiio with the output impedance calculated from the speced power per load impedance.

FiiO rates it at < 10?.

"I would basically never trust the published specs, "

I'll let you draw your own conclusions as to why the specs are contradictory.

• skamp
• Developer
Sennheiser HD800: What type of amp do I need?
##### Reply #27 – 25 December, 2012, 08:29:52 AM
I used formulas from NwAvGuy's blog and I came up with 12.279Ω, which is much closer to the rated spec. I must admit that I'm a highschool drop-out and I haven't had to solve an equation in nearly 15 years, so my math is pretty foggy.

Code: [Select]
`V = sqrt(P * Zhp)Vload1 = sqrt(1W * 16Ω) = 4VVload2 = sqrt(0.08W * 600Ω) = 6.928VZout = (Zhp * (Vnoload - Vload)) / VloadZout = (16Ω * (Vnoload - 4V)) / 4VZout = (600Ω * (Vnoload - 6.928V) / 6.928VVnoload = (Zout * 4V / 16Ω) + 4VVnoload = (Zout * 6.928V / 600Ω) + 6.928V(Zout * 6.928V / 600Ω) + 6.928V = (Zout * 4V / 16Ω) + 4V(Zout * 6.928V / 600Ω) + 2.928V = Zout * 4V / 16Ω(Zout * 4V / 16Ω) - (Zout * 6.928V / 600Ω) = 2.928V(Zout * (4 / 16 * 600) / 600) - (Zout * 6.928 / 600) = 2.928(Zout * 150 / 600) - (Zout * 6.928 / 600) = 2.928(Zout * 150) - (Zout * 6.928) = 2.928 * 600 = 1756.8Zout = 1756.8 / (150 - 6.928) = 12.279Ω`

I checked and that value is a match with the Vnoload and Zout formulas above:

Code: [Select]
`Vnoload = (12.279Ω * 4V / 16Ω) + 4V = 7.069750VVnoload = (12.279Ω * 6.928V / 600Ω) + 6.928V = 7.069781VZout = (16Ω * (7.069750 - 4V) / 4V = 12.279ΩZout = (600Ω * (7.069781 - 6.928V) / 6.928V = 12.278954Ω`
See my profile for measurements, tools and recommendations.

• IgorC
Sennheiser HD800: What type of amp do I need?
##### Reply #28 – 25 December, 2012, 11:24:13 AM
Can I ask You how did You get 1W, 0.08W, 16Ω and 600Ω values? I ask because these measurements have an error range that can have siginificant influence on final result and its calculation steps.

• skamp
• Developer
Sennheiser HD800: What type of amp do I need?
##### Reply #29 – 25 December, 2012, 11:32:18 AM
The manual for the E09K gives 900 mW into 32Ω and 150 mW into 300Ω, which computes into an output impedance of 9.231Ω, which happens to be within the rated < 10Ω.
See my profile for measurements, tools and recommendations.

• GSARider
Sennheiser HD800: What type of amp do I need?
##### Reply #30 – 25 December, 2012, 03:47:08 PM
I guess the short answer is that I will find out how they sound when I get them and pair them up with the Fiio's...

Again, the Ie80's and Amperiors that I already have sound fantastic via the E17 on its own, but when I dock the E17 into the E09K and go via my iMac - not so good, sounds flat in comparison. Hence why I'm trying to ascertain if the HD800's will be any better.

Sennheiser HD800: What type of amp do I need?
##### Reply #31 – 25 December, 2012, 05:28:36 PM
I guess the short answer is that I will find out how they sound when I get them and pair them up with the Fiio's...

Again, the Ie80's and Amperiors that I already have sound fantastic via the E17 on its own, but when I dock the E17 into the E09K and go via my iMac - not so good, sounds flat in comparison. Hence why I'm trying to ascertain if the HD800's will be any better.

Well, you won't get the same amount of bass on the  hd800, regardless of  your source.

• GSARider
Sennheiser HD800: What type of amp do I need?
##### Reply #32 – 25 December, 2012, 05:33:55 PM
Everything sounds flat, not just the bass.

• IgorC
Sennheiser HD800: What type of amp do I need?
##### Reply #33 – 25 December, 2012, 08:02:06 PM
Probably because E17 has enabled gain at +6dB that makes the sound alive, punchier and when E17 is used with E09K the gain isn't enabled. Try to disable gain on E17 and see if it sound comparables to E17+E09K.

As for me, I'm not impressed with E17 driving HD 650 and HD 800. It's ok  but not as clean enough as my EMU Pre Tracker in my experience. Nobody knows  how E17 decodes the 44.1 kHz input because it shows the same 48 kHz sampling rate for both 44.1 and 48 kHz files. Does it use some resampler internally? If so, how good is it? It doesn't support 24bits decoding for CD material (44.1 kHz). As it was so hard to do, but it does support 96 kHz, 24 bits. The default +6dB gain that misleads people.
And many other little or not so little flaws those destroy a listening experience. Disappointments. It's not a truly professional device, sorry Fiio, it's not.

That's why  a next amp+dac I want to try is 02/ODAC.

• GSARider
Sennheiser HD800: What type of amp do I need?
##### Reply #34 – 25 December, 2012, 08:21:48 PM
Have been experimenting earlier this evening as I got my optical link cable. So I docked the E17 into the E09K then plugged the cable into the E17 and connected to the iMac...sounds a lot better with my Amperiors and comparable to the E17, if not actually better. You're right on the 6db gain setting on the E17 btw, it's what I keep it at as well.

The Eq settings still seem enabled with the E17 docked too.

Sennheiser HD800: What type of amp do I need?
##### Reply #35 – 25 December, 2012, 08:25:31 PM
Sorry if what I  said was confusing.
I  meant: you  won't get the same amount of bass with hd800, compared to ie80 & amperior.
I've actually have the senn ie7 (which is more or less similar to the ie80),
and the hd25 II 1 (which is similar to amperior).
It's not exactly the same satisfaction to listen bass heavy techno on the senn ie7, and with the hd800.
And the hd25 II 1 is not as good as the senn ie7 (at least for my taste) but basically offers some mid bass emphasis.
I  know people that have listened the hd800, and quickly made the conclusion it was not for them.

• GSARider
Sennheiser HD800: What type of amp do I need?
##### Reply #36 – 26 December, 2012, 06:05:44 AM
I have listened to it extensively before deciding, my only concern is driving them properly.

Sennheiser HD800: What type of amp do I need?
##### Reply #37 – 26 December, 2012, 06:40:23 AM
I have listened to it extensively before deciding, my only concern is driving them properly.

Well, ok, I'd be interested by your results.
Otherwise, I've seen people thinking that the hd800 sounds even great from an ipod,
but I  think it's a not a so good idea.
Personally between my cowon player & my xonar stx, I  prefer to plug my hd800 on the latter.

• IgorC
Sennheiser HD800: What type of amp do I need?
##### Reply #38 – 06 January, 2013, 06:22:23 PM
My last post about E17 driving HD 800 was quite negative. It's different with HD 650. One can say that they sound softer, warmer, forgiving. After some sessions I'm quite pleasant with E17 driving HD 650.

One possible explanation can be that HD 800 aren't quite neutral comparing to flat reference HD 650. HD 800 vs HD 650.
And E17 has more distortion in high frequencies where HD800 occasionally has a bump, causing unmasking/amplification of distortion.  Sometimes I hate HD800 for its peak in that frequency range as my ears get tired after some time because of it.

• dhromed
Sennheiser HD800: What type of amp do I need?
##### Reply #39 – 23 April, 2013, 05:30:51 AM
It's a \$1500 headphone, presumably there is a reason it costs this much.

Nope.

• tpijag
Sennheiser HD800: What type of amp do I need?
##### Reply #40 – 23 April, 2013, 09:42:19 PM
Wow! join a forum and post one nearly valueless, placebo driven drivel and follow up with an insult instead of considering any of the TOS service you agreed to when joining.

• saratoga
Sennheiser HD800: What type of amp do I need?
##### Reply #41 – 23 April, 2013, 09:58:52 PM
I think the Auditor is a great amp however and a bang for your buck winner.

Its really overkill for those headphones.  The sensitivity is high enough that you probably never use more than a small fraction of the amp's voltage range, so its kind of wasted.

Sennheiser HD800: What type of amp do I need?
##### Reply #42 – 24 April, 2013, 06:51:17 AM
It's a \$1500 headphone, presumably there is a reason it costs this much.

Nope.

It is hard to escape that conclusion.

I think that what manufacturers  such as Sennhesier are doing with ultra-high priced headphones is simple crass profiteering on a illogical aberration in the marketplace.

Sennheiser HD800: What type of amp do I need?
##### Reply #43 – 24 April, 2013, 07:17:05 AM
It's a \$1500 headphone, presumably there is a reason it costs this much.

Nope.

It is hard to escape that conclusion.

I think that what manufacturers  such as Sennhesier are doing with ultra-high priced headphones is simple crass profiteering on a illogical aberration in the marketplace.

I can't argue your idea that these are expensive, nor can I convince anyone of their worth. Those are personal decisions that you and others will wrestle with...

I think the Auditor is a great amp however and a bang for your buck winner.

Its really overkill for those headphones.  The sensitivity is high enough that you probably never use more than a small fraction of the amp's voltage range, so its kind of wasted.

I am not an SPL engineer. In other words, it's not possible for me to respond to your comment with same technical assurance that you possess.

• db1989
• Global Moderator
Sennheiser HD800: What type of amp do I need?
##### Reply #44 – 24 April, 2013, 08:43:26 AM
theancient, please back up your claims with valid data proving that they were worth bumping this thread after 3.5 months, or stop posting unverifiable impressions and FUD about the price-tag, as well as insinuating that others’ disagreement is due to reduced mental capacity on their part. Articles 8 and 2 of the Terms of Service, to which you agreed during your registration, are pertinent here.

• skamp
• Developer
Sennheiser HD800: What type of amp do I need?
##### Reply #45 – 24 April, 2013, 09:23:04 AM
Sometimes, an item's worth is what the client is willing to pay for it. I'm sure Sennheiser's marketing department came up with that ridiculously high price because they thought it was the sweet spot of what their niche target customer base would be willing to pay. Note that they have every price point covered with a gazillion models ranging from, what, 20 bucks? all the way to \$1,500.
See my profile for measurements, tools and recommendations.

Sennheiser HD800: What type of amp do I need?
##### Reply #46 – 24 April, 2013, 12:34:04 PM
Sometimes, an item's worth is what the client is willing to pay for it. I'm sure Sennheiser's marketing department came up with that ridiculously high price because they thought it was the sweet spot of what their niche target customer base would be willing to pay. Note that they have every price point covered with a gazillion models ranging from, what, 20 bucks? all the way to \$1,500.

Well the hd800 is the only headphone that  comes currently with a ring driver.
It's also using a metal mesh for the opening.
So regarding the conception only, it's not the same as "gazillion" of other models.
Off course , the question is how much some "the ring driver", or the "metal mesh" impacts sound quality.
I'm convinced that the hd800 are (very) overpriced.
But they are good ,  and someone that like their sound signature , would be easily indulgent regarding the price too.

Sennheiser HD800: What type of amp do I need?
##### Reply #47 – 24 April, 2013, 06:18:22 PM
theancient, please back up your claims with valid data proving that they were worth bumping this thread after 3.5 months, or stop posting unverifiable impressions and FUD about the price-tag, as well as insinuating that others’ disagreement is due to reduced mental capacity on their part. Articles 8 and 2 of the Terms of Service, to which you agreed during your registration, are pertinent here.

I got here through Google because I was looking for other impressions of the HD800 with the Auditor, if this is problematic for you maybe you should write Google and ask that they not direct people to your website.

• greynol
• Global Moderator
Sennheiser HD800: What type of amp do I need?
##### Reply #48 – 24 April, 2013, 06:45:35 PM
I got here through Google because I was looking for other impressions of the HD800 with the Auditor, if this is problematic for you maybe you should write Google and ask that they not direct people to your website.

You were presented the rules when you registered; you agreed to them.  If you can't follow them then don't post.  It's that plainly simple.

Google didn't tell you to post here and if they did you weren't obliged to comply.  You are obliged to comply with our terms, however.

PS: Your offending posts were moved to the recycle bin and titled per the rules that were broken.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Sennheiser HD800: What type of amp do I need?
##### Reply #49 – 24 April, 2013, 10:52:13 PM
I got here through Google because I was looking for other impressions of the HD800 with the Auditor, if this is problematic for you maybe you should write Google and ask that they not direct people to your website.

PS: Your offending posts were moved to the recycle bin and titled per the rules that were broken.

You're very wise to do that, bravo.