[BillsonChang007]

Page not found on mine

 

[depleted]

His first link lacks a 0, try clicking the second link or adding the zero in 900 to make it 9000

 

[superjawes]

Do we have a math whiz around here? I notice that many headphones have impedances that differ from some of the listed power ratings, which is why dB SPL is often estimated. If we have a few ratings, we should be able to approximate dB SPL a little closer than using the nearest listed impedance.

It might not be worth the trouble of implementing something else, but it can't hurt to understand the math.

 

[haslaughz]

 
Suggestions:
 

1. The "Match" rating needs a tooltip explanation. I'm not sure what this calculation is intended to convey.
2. Calculate and display minimum amplifier power required to reach target SPL output for each headphone. We usually provide customers with minimum output power for 110-120dB in 2.5dB in increments.
3. Provide reference tooltips to explain SPL, headphone impedance, amplifier output impedance, sensitivity, damping factor. Most people seeing a tool like this need the information because they lack an understanding. Give users as much concise knowledge as possible.

 
- Removed the "match" rating as it was causing much confusion. Instead, the tool will return 10 recommended amps.
- Added power requirements by 2.5 dB steps in headphone specs.
- Added some tooltips
 
I'd like to incorporate amp gain into the calculations. Any recommendations on the most useful way to surface this info?

 

[haslaughz]

Do we have a math whiz around here? I notice that many headphones have impedances that differ from some of the listed power ratings, which is why dB SPL is often estimated. If we have a few ratings, we should be able to approximate dB SPL a little closer than using the nearest listed impedance.

It might not be worth the trouble of implementing something else, but it can't hurt to understand the math.

 
For amps that don't list power output at the headphone's given impedance, I estimate based on an article.
 

Quote:
 

1. Power Specified At A Lower Impedance – In this case you want to figure out the voltage at the lower impedance and use that instead. The math is V = SquareRoot( Power in Watts * Impedance ). So for the FiiO E7, for example, it’s SquareRoot ( 0.15 * 16 )  = 1.5 Vrms.
2. Power Specified At A Higher Impedance – It’s impossible to accurately predict a source’s behavior into impedances lower than specified when you don’t know the output impedance or maximum current. The Leckerton UHA-4 example above shows how it goes wrong with current limiting. And the E9 shows how it goes wrong due to its higher (10 ohm) output impedance. The E9’s 80 mW into 600 ohms gives: SquareRoot ( 0.080 * 600 ) = 6.9 Vrms which should yield 3 watts at 16 ohms, but the E9 only manages 1 watt or 4 Vrms because a lot of power is lost due to the 10 ohm output impedance. A very rough estimate can be obtained by calculating the voltage at the next higher impedance, and then dividing that value by four to calculate power at lower impedances.

 

 

[jodgey4]

I like the cut of your jib, OP.

 

[Captain Howdy]

We need more 'hard data' like this around here. Head-fi is a great resource, but hundreds of people stating their personal opinions (which often change over time) is really of limited value, especially to newbies such as myself.

 

[Music Alchemist]

  We need more 'hard data' like this around here. Head-fi is a great resource, but hundreds of people stating their personal opinions (which often change over time) is really of limited value, especially to newbies such as myself.

 
OMG, genius username/avatar! My high school chemistry teacher grew up with Linda Blair.

 
At any rate, subjective impressions and objective data are equally valuable, in my book.

 

[MindsMirror]

Do we have a math whiz around here? I notice that many headphones have impedances that differ from some of the listed power ratings, which is why dB SPL is often estimated. If we have a few ratings, we should be able to approximate dB SPL a little closer than using the nearest listed impedance.

It might not be worth the trouble of implementing something else, but it can't hurt to understand the math.

The headphone impedance and the amp's output impedance form a voltage divider.
 
When the amplifier is not current limited, if you know the power delivered to a headphone with a certain load impedance, and you know the output impedance of the amp, you can find the open loop voltage and then should be able to calculate the current and power delivered to any load.
 
If you know the amp is on it's current limit, the current through the load will be the same so you can find the current and power delivered to any load.
 
I'm not sure if this information would be useful for the site, since I'm not sure how easily you can tell when the amp is current limited. If the amp is not current limited then power delivered should increase as the load impedance approaches the amp's output impedance, and that doesn't seem to be the case with all of the amps, indicating that some of them are current limited with lower impedance loads.

 

[audidym]

When selected Dt880 600Ohms and Fiio E09k, the notes section says " This amp might have enough power to adequately drive these headphones"
 
Fiio E09k Power output at 600ohms is 80mW which is sure enough to drive Dt880 600Ohms at 115dB SPL without any problem.
 
Ultimately how good Fiio e09k compares to Tube Amp is not the story the note section tries to say,so it can be changed to " This amp has enough power to adequately drive these headphones"

 

 

[haslaughz]

First off, this is a great idea. Second, here are some suggestions:

1. Mjolnir is a special-case amp, as it cannot run single-ended headphones, and that's the kind of important thing that should be noted on it, since you'll need both a balanced set of cans and a balanced cable to actually use it. Generally, though, I think that each entry could use something like that in the notes, like pointing out which amps have tubes, what kind of outputs are provided, etc.

2. As others have noted, I don't think that you should solely base synergy on impedances and SPL. Higher impedance headphones might actually pair well with higher impedance amps, but your calculations give a big bias towards low impedance amps. There's also a discussion in Sound Science about whether or not dampening factor is relevant for orthodynamic/planar magnetic headphones. It might still be a good rule of thumb for efficiency, but I think the biggest goal is overall power delivery to planars, as they tend to be less efficient.

Perhaps you should add some sort of karma system for each pairing. Note that it is user generated, then allow people to thumb up particular combinations. This should help to capture some combinations that users enjoy (like how HD600, HD650, and HD800 owners seem to like tube amps).

3. This might be more important as the database grows, but having other sort and filtering functions could sidestep concerns from #2. It could be an easy way of eliminating combinations where dampening factor is <10, for example.

4. Prices. This will be very difficult with dynamic prices and discontinued models, but I think it would be extremely useful to see how much each component costs. Even if the metrics say that a combination is good, I don't think that anyone wants to spend more on the amp than on the headphones, so adding the price would let people know if an amp is in a sensible price range for the paired 'phones.

Good luck, and thanks for starting this!

 
1. Added a field indicating if the amp has balanced inputs only.
2. For planar magnetics, I've applied a 3X multiplier to the requirements to indicate the demanding nature of these type of headphones. (Is 3X too much? Too conservative? Thoughts)

 

[Music Alchemist]

  1. Added a field indicating if the amp has balanced inputs only.
2. For planar magnetics, I've applied a 3X multiplier to the requirements to indicate the demanding nature of these type of headphones. (Is 3X too much? Too conservative? Thoughts)

 
It's too much, because only a few planar magnetic headphones are that highly demanding. I advise consulting with the manufacturers to get accurate multipliers and whatnot.

 

[superjawes]

I actually think that planars were fine once you removed the "% synergy" calculation. My point was that the metrics seemed to favor higher damping factors (lower output impedance) even though anything over 10 should be very good. Just going with "higher damping factor is better" could hurt pairings between high impedance headphones with tube amps with higher output impedance.

I think the main focus of headphone to amp pairings should be power, and calculating damping factor should just be a check of whether or not you're in a "good" range (that is, just make sure it's over 10).

Planars really only want power. Following a >8 (or 10) damping factor rule is useful to make sure you aren't losing a bunch of power to the source impedance, but as long as the amp can provide enough power, damping factor shouldn't be a problem, and you should be able to judge dB SPL the same as you would for dynamic headphones.

 

[superjawes]

Side note...does anyone know where to track down the Specs of Asgard, Valhalla, and Lyr 1? I wanted to suggest them as reference products for Audiobot, but can't seem to find them...

 

[Music Alchemist]

Side note...does anyone know where to track down the Specs of Asgard, Valhalla, and Lyr 1? I wanted to suggest them as reference products for Audiobot, but can't seem to find them...

 
Go to Schiit Audio's website and click on the specs tab for the corresponding products.