I have been an owner of Hegel H190 which I use in my living room and I recently started putting together my next system around AHB2 for my home office and as the pieces arrived I decided to A/B test the two stacks. I tried to be systematic as much as possible, but by all means critique my protocol.
Systems under test:
A: Qobuz via Roon core on Mac mini -> USB -> Topping D90SE 4V output DAC only mode -> Topping Pre90 -> Benchmark AHB2 in Low Gain
B: Qobuz via Roon core on Mac mini -> USB -> Hegel H190
I tested these two with my JBL L100 classic speakers.
I level matched both setups with a digital multimeter with both 300Hz and 1KHz tones up to +/- 5mv difference. This meant setting the volume on H190 to 35, and the gain on Pre90 to -33dB. The reason I also checked with 300Hz was that the specified frequency range for the AC input on the multimeter was 400Hz. Nevetheless the outputs were pretty similar for both test signals. I noticed that there is a slight (about 4mv) imbalance between the left and right channels of the Hegel.
To carry out the test I used a passive A/B switch box I got from amazon:
I used two pairs of exactly the same set of cables to connect the speaker outputs of the two amps and routed them inside a "randomization" shoe box with holes on each side, and asked my partner to connect the other ends to the left most and right most terminals of the switch. So basically I had no idea which button was which amp. The speakers were connected to the speaker output of the switch box.
Both setups were visible in Roon, and I grouped them together as a single zone to play a playlist of test tracks to both at the same time. I made sure that the highest resolution track in the playlist was 96 Khz/24bit to be fair to Hegel H190 whose USB input cannot handle higher resolutions. These are the tracks I used (I am quite familiar with most of these) in Artist | Track | Result format. The Result field is either L if I prefer the sound of the leftmost button, R if I preferred what's controlled with the rightmost button, or N if I had no preference or I couldn't tell the difference.
1- Grimes | Vanessa | N
2- Nina Simone | Sinnerman | R
3- Air | Cherry Blossom Girl | N
4- Beethoven | Symphony No. 5, Carlos Kleiber Wiener Phil, Allegro con brio | N
5- Celeste | Tell me Something | N
6- Dire Straits | Money for Nothing | R
7- Moloko | The Time is Now | R
8- Daft Punk | Give Life Back to Music | N
9- Michael Jackson | Billie Jean | N
10- Judas Priest | Pain Killer | N
For the most part I couldn't tell the difference between the two setups no matter how much I went back and forth to moments in these tracks that I consider myself intimately familiar with. It was mostly as if I was listening to exactly the same thing. For three tracks, I did pick system R on a quite faint preference, but really kind of forcing myself to chose.
Now time to unveil what were L and R. I switched the output to system R and it was still playing the last track, and then pressed the off button on Hegel's remote. The music stopped.
I listened to the tracks that I had shown a preference for again and I am convinced I couldn't have heard a difference. I think psychologically I was rooting for Benchmark to win as it's my new system and I have been a bit sore about Hegel based on recent reviews. So I think subconsciously I may have tried to identify what sounded like Benchmark from my audio memory and pick that. Unfortunately once I made that choice the first time, I became kind of biased to it, so lack of randomness between songs is kind of the weakness of my protocol I think.
Systems under test:
A: Qobuz via Roon core on Mac mini -> USB -> Topping D90SE 4V output DAC only mode -> Topping Pre90 -> Benchmark AHB2 in Low Gain
B: Qobuz via Roon core on Mac mini -> USB -> Hegel H190
I tested these two with my JBL L100 classic speakers.
I level matched both setups with a digital multimeter with both 300Hz and 1KHz tones up to +/- 5mv difference. This meant setting the volume on H190 to 35, and the gain on Pre90 to -33dB. The reason I also checked with 300Hz was that the specified frequency range for the AC input on the multimeter was 400Hz. Nevetheless the outputs were pretty similar for both test signals. I noticed that there is a slight (about 4mv) imbalance between the left and right channels of the Hegel.
To carry out the test I used a passive A/B switch box I got from amazon:
Nobsound 4-way Stereo Speaker Selector Switch Box Audio Amp Distributor Splitter Hub 200W: Amazon.co.uk: Electronics & Photo
Free delivery and returns on eligible orders. Buy Nobsound 4-way Stereo Speaker Selector Switch Box Audio Amp Distributor Splitter Hub 200W at Amazon UK.
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I used two pairs of exactly the same set of cables to connect the speaker outputs of the two amps and routed them inside a "randomization" shoe box with holes on each side, and asked my partner to connect the other ends to the left most and right most terminals of the switch. So basically I had no idea which button was which amp. The speakers were connected to the speaker output of the switch box.
Both setups were visible in Roon, and I grouped them together as a single zone to play a playlist of test tracks to both at the same time. I made sure that the highest resolution track in the playlist was 96 Khz/24bit to be fair to Hegel H190 whose USB input cannot handle higher resolutions. These are the tracks I used (I am quite familiar with most of these) in Artist | Track | Result format. The Result field is either L if I prefer the sound of the leftmost button, R if I preferred what's controlled with the rightmost button, or N if I had no preference or I couldn't tell the difference.
1- Grimes | Vanessa | N
2- Nina Simone | Sinnerman | R
3- Air | Cherry Blossom Girl | N
4- Beethoven | Symphony No. 5, Carlos Kleiber Wiener Phil, Allegro con brio | N
5- Celeste | Tell me Something | N
6- Dire Straits | Money for Nothing | R
7- Moloko | The Time is Now | R
8- Daft Punk | Give Life Back to Music | N
9- Michael Jackson | Billie Jean | N
10- Judas Priest | Pain Killer | N
For the most part I couldn't tell the difference between the two setups no matter how much I went back and forth to moments in these tracks that I consider myself intimately familiar with. It was mostly as if I was listening to exactly the same thing. For three tracks, I did pick system R on a quite faint preference, but really kind of forcing myself to chose.
Now time to unveil what were L and R. I switched the output to system R and it was still playing the last track, and then pressed the off button on Hegel's remote. The music stopped.
I listened to the tracks that I had shown a preference for again and I am convinced I couldn't have heard a difference. I think psychologically I was rooting for Benchmark to win as it's my new system and I have been a bit sore about Hegel based on recent reviews. So I think subconsciously I may have tried to identify what sounded like Benchmark from my audio memory and pick that. Unfortunately once I made that choice the first time, I became kind of biased to it, so lack of randomness between songs is kind of the weakness of my protocol I think.