The Quickstep uses a 9V battery but you can also connect a power supply to it, both are located on the back of the amplifier. The 9V battery is very easy to remove and you don’t need any tools to do so. One of the advantages of the 9V battery is that the Corda Quickstep sounds extremely clean, I myself have been using it with rechargeable 9V batteries only, not with a power supply which is also supposed to boost the output volume. These 9V batteries don’t last quite as long but a 9V battery charges pretty quick. To be honest, one recharged battery doesn’t get me through a full working day so when you are planning on using the Quickstep for longer periods, I suggest getting a power supply for it. The Quickstep comes with two gain settings (-3dB / 14dB) and I can assure you it can play really loud. The volume pot is discrete and has 32 1.5dB steps. It’s so smooth to turn and it lets you set the volume just how you want it, even with sensitive and very easy to drive monitors.
Mr. Meier continuous: “The Corda Quickstep is a technically very sophisticated portable amplifier. This amp was designed to provide the best possible portable sound with a minimum of compromises towards size and current consumption. The amp not only uses the concept of active balanced ground but also has a discrete volume control. This volume control isn’t a standard industrial solution but uses a concept in which the position of an analog potentiometer is measured using a low-power ADC and in which the output of this ADC is used to control electronic switches that set the volume level. The 3.5 mm sockets, mechanically often the weakest point of a portable amplifier, are heavy duty. Also much care is taken that the amp does not react to RF-signals at the input, thus making it immune to RF-pollution caused by mobile headphones.
For its amplification the Quickstep uses five single OPA209 opamps for maximal sonic performance. (No dual or quad opamps!) If you’re talking about Meier gear, you have to know that each and every unit is engineered in the best possible way. I have to admit it isn’t always easy to follow Mr. Meier’s explanations but he’s an incredibly gifted designer and his knowledge is recognized and appreciated by a whole lot of other engineers. The Quickstep comes with 2 mini-mini interconnects (gold plated) and a tool to open the amp. Its price outside of Europe is €295,- / USD 325,- and for the EU residents it costs €345. The Corda Quickstep isn’t a cheap amplifier but don’t forget you’re getting a superbly designed amplifier with top quality components in a very small and powerful package. It also is an amplifier that manages to drive full sized headphones without any problem but more on that in “Sound”. Here are the rest of the Quickstep specs:
- Supply voltage: 6 .. (9) .. 15 Volts DC
- Mean current uptake: 35 mA / 20mA (high/low-current-consumption-mode)
- Active balanced headphone ground.
- Star-grounding and ultra-short signal paths.
- Input impedance: 120 / 17 kOhm
- Output impedance: < 1 Ohm
- The unit runs from a single 9V battery and internally the supply voltage is used to create a pair of +4.5 and -4.5V powerlines (low current consumption mode) or a pair of +9 and -9V powerlines (high current consumption mode).
- External power supplies can be connected with voltages between 6V and 15V DC. This supply voltage is internally doubled to create a pair of +6..+15V and -6..-15V powerlines.
- Noise is removed by extensive LC-filtering of the supply voltage.
- RF-noise (iPhone!!) is removed by extensive filtering of the input signal.
- The total buffer capacity is 4700 uF to lower the effective battery impedance.
- The heavy-duty (!!) 3.5 mm sockets are gold-plated.
- Inside the signal path only metal-resistors and high-quality film-capacitors are used (polypropylene).
According to Mr. Meier, his design results in a very clean and detailed sound without any channel imbalances and right he is. The lovely volume pot lets you set the volume exactly how you want to set it. There are no noises, no distortion, no cracks. You get a perfectly silent amp with a full black background. Everything is detailed, clean and clear with great dynamics. The sounds stage width is good and its depth is too. Separation and balance are well done.
Bass is present when needed but doesn’t always have the biggest body, this isn’t an amp for the bass heads out there. While the bass detail and layering certainly is there, it isn’t always of the tightest kind. That however should improve when using an external power supply instead of the 9V battery (but I can’t confirm it). The mids are gorgeous and have the perfect mix between detail and musicality. Separation, spaciousness and depth are good and the Corda Quickstep delivers a very natural engaging sound. The overall sound signature of the Quickstep is neutral but the good kind of neutral where musicality is most important. The Corda Quickstep simply is transparent and doesn’t anything to the sound itself. Treble is clear and detailed but always easy to listen to. It never is too hot or sibilant.
The Quickstep makes the Sennheiser HD650 sound very dynamic and clear. Low gain works just fine with only 11 o’ clock on the volume dial. I still prefer the Sennheisers on tubes but the Quickstep makes the HD650 sound alive, layered, fast, clear and precise. I would have liked a little more bass impact but most of you who sometimes find the HD650 to sound too dark will love it on the Quickstep. Most of the time I used the Senn in combination with the Chord Mojo as its source. I actually prefer the HD650 directly out of the Quickstep over the headphone out of the Mojo. Layering is better and there’s more weight in bass and mids. The Mojo sounds more forward and forced then the Quickstep.
Sound continues after the CLICK