To recap, last week we explained OTW#3: the max power of the micro iDSD at 4000mW@16ohm/8v line output.
This was achieved under the “Turbo” mode. This along with some of the questions asked, nudged the spotlight towards Outta This World #2. You lot sure are eager…
Outta This World #2
Perfect Headphone Pairing:
With Turbo/Normal/Eco + iEMatch
Background
In any audio system, the matching between the amplifier and the transducers is arguably the most crucial.
In the loudspeaker market, speaker + amplifier matching is typically well-matched.
i.e. low-powered amplifiers are paired with high-efficiency speakers and vice versa.
HOWEVER, in the headphone market, the gamut of headphones paired with headphone amplifiers is very inconsistent. This often leads to poor-matching from not enough power to drive headphones (typically: unimpressive sonics) to far too much power to drive in-ears (typically: unusable volume control + excessive hiss).
Explanation
In the headphone market, we went through virtually every current production headphone out there and what we found shocked us.
Running the rule over current production headphones, we found that there is a
massive 53dB difference between the most efficient In-Ear-Monitors (IEMs) and the most inefficient headphones. This is an absolutely enormous range (think of this as the difference in loudness between a disco and a quiet library so this is NOT subtle.)
At one end of the spectrum is the HiFi Man HE-6 which is as hungry as things go. Rated at 90dB/V, this “Hummer” of a headphone needs well over 3,000mW to drive properly to good levels. Let’s categorise these as low-efficiency headphones.
BTW, for the K1000 die-hards out there, it is the "Mack juggernaut" as it is rated crazily low at 84dB/V!!!
At the other end of the spectrum are super-efficient IEMs. The Sennheiser IE800 is rated at 143dB/V and even driven by the iPhone’s paltry 15mW, you can only dial-up to 50% of its digital volume before it starts to encroach upon ear-damaging levels! Let’s categorise these as ultra-sensitive IEMs.
It is not surprising to find that we had yet to come across a headamp that can deal with this gamut let alone a DAC headamp that is portable that can deal with this full spectrum of headphones!
How best to consider the max power output and the perfect headphone pairing?
The micro iDSD has max power output of 4000mW.
The Porsche 911 Turbo S, has a maximum power output of 560bhp. To put all that power down onto the tarmac and to ensure that it grips the road to very best ability of the driver’s demands, it has Sport Plus/Sport/Comfort (see Sport buttons below). To zero-in that perfect-setup, the Porsche Dynamic Chassis Control (see PDCC button below) further fine tunes the whole of the car’s drivetrain to ensure maximum grip.
The micro iDSD has Turbo/Normal/Eco and in conjunction with iEMatch, the listener is able to dial-in the IEM/headphone used.
Unleash the beast! (we mean the micro iDSD + your headphones, not the 911 Turbo!)
How does this benefit the listener?
OTW #2 is the
perfect-match of headphones with the micro iDSD.
For the very first time ever, from the Sennheiser IE800 > HiFi Man HE-6, the listener is able to “dial-in” the perfect match using a combination of the micro iDSD’s Power Modes + iEMatch.
For example:
HE-6: Power mode = Turbo and iEMatch = Off
IE800: Power mode = Eco and iEMatch = Ultra-Sensitivity
These are of course, the two polar opposites so with any other headphone or in-ear-monitor, then adjust the different settings under Power mode + iEMatch to suit.
Summary Table of Power Mode + iEMatch
Technology | Description | Remarks | Approx Playing Time |
HP Amp Power | | | |
• Turbo mode | 8.0V/4,000mW@ 16Ohm | > 1000 mW @ 64 Ohm | 6 hours |
• Normal mode | 4.0V/1,000mW@16Ohm | > 500 mW @ 32 Ohm | 8 hours |
• Eco mode | 2.0V/250mW@ 16Ohm | > 250 mW @ 16 Ohm | 12 hours |
| | | |
Technology | Description | Remarks | |
iEMatch | | | |
| • Ultra-Sensitivity | eg Sennheiser IE800/Shure SE535 | |
| • High-Sensitivity | eg Ultimate Ears UE900/Sennheiser Momentum | |
| • Off | eg On-Ear or Over-Ear headphones | |
| | | |
Once this has been dialled-in to suit the listener, then the analogue volume control of the micro iDSD can be cranked up to 12 o’ clock or more where it will really start to bloom and let your music shine through.
ps. For Kugino. If England loses today, we may not have upload OTW#2 for one week. So we thought we'd better get this Outta The Way (OTW)