My audio connective trail and setup:
16 & 24-Bit WAV lossless files,
Foobar2000 with WASAPI event output,
Nordost Blue Heaven USB type B cable/Oyaide Neo d+ class S USB type B cable/custom Nordost USB type B cable,
iFi micro iUSB purifier,
Nordost Blue Heaven USB type B cable/Oyaide Neo d+ class S USB type B cable/custom Nordost USB type B cable,
Fostex HP-A4BL DAC connected to a iFi iPower 12 volt power supply/HRT Music Streamer Pro DAC/Pro-Ject Pre Box S2 Digital,
Nordost Heimdall RCA cable/Oyaide Neo d+ class S RCA cable,
Beyerdynamic A1 amplifier (with a HiFi Tuning gold-plated ceramic silver wire internal fuse) connected to a custom Nordost Vishnu power
cable (with a IsoClean 24k gold-plated plug, a Furutech FI-11 gold-plated IEC connector and HiFi Tuning gold-plated fuse),
all connected to a custom Russ Andrews Yello power mains extension with a Supra gold plated UK mains plug with a gold plated AMR fuse inside.
High end headphones and earphones I used on the A1: Focal Utopia, Sennheiser HD 800, Beyerdynamic T1, Grado GS2000E, HiFiMan Edition X V2, AKG K3003, Sennheiser IE 800.
Hi everyone.
I will keep this brief initially and will update in time. I have been very lucky to use quite a few different headphones and earphones with the A1 as mentioned above, I have used more but the list would be pretty long.
The amp has been thoroughly burned in with a minimum of 300 hours.
My previous amps:
Beyerdynamic A20,
Pro-ject Head Box S,
Graham Slee Novo,
Hifiman EF2C with Voskhod tubes,
Little Dot I+ with a Hi-fi Tuning Supreme internal fuse.
During my time with the A1 I bought a few other amps:
Grado RA1 battery powered,
Micromega MyZIC,
Burson Soloist SL MK2,
Beyerdynamic A20 again.
It is quite tricky to review an amp. There are quite a few factors that affect it's output like the source/DAC,
RCA cables and power cables. You can even change it's internal fuse (T100L 250V 20mm x 5mm).
I know I have used only 2 tube amps but I found the A1 to be my favourite of all amps.
I do prefer solid state amps but will look to try more tube amps in the future.
The A1 has so much power and authority, it has driven every single headphone I can throw at it with consummate ease.
I think it is a warm sounding solid state amp with good pace and speed, great mids and vocals, very good treble and detail, excellent lows and bass extension with a good soundstage.
I found the Soloist SL MK2 to be a little more open and airy with a slightly bigger sound stage but I preferred everything else on the A1.
The battery powered RA1 was not powerful enough to drive all my headphones but it was slightly warmer.
The A1 is the most quiet or silent amp I have used with my earphones and I really enjoy cable rolling on the A1 : )
I've used many different Nordost power and RCA cables on it and I am currently trying a pure silver power cable.
The Alps potentiometer is excellent, you can make very small volume adjustments indeed.
I hope that Beyerdynamic create a fully balanced version of this one day, the A1 is expensive for what it is and they should look to be more competitive from a value point of view. It does not even have a balanced input, every port is unbalanced.
But I regard the performance and versatility of the A1 as world class, it has given me some unforgettable audio experiences especially with the Utopia. And the HD 800 too.
This amp is so good it even brought out the lows from my AKG Q701! Many people think that awesome headphone is lacking in bass.
I highly recommend this German piece of engineering.
Update 1.
I have to deduct half a star as it is not as versatile as I thought, it has a 100 ohm impedance output so it is designed for higher impedance headphones.
