Let’s start with the Beyerdynamic headphones as it seems like the right thing to do. I chose the analytical T70, the huge sound stage T90 and the 32Ohm DT770 for testing a low impedance dynamic headphone as well.
The T90, which I normally use with my 339 or Crack loves the extra warmth of the tubes. Well, I should really say I still like the extra tube warmth in the T90 after pairing it with the A20. The A20 gives a nice kick in the bass and you get a great sound stage with a lot of air and detail, the T90 characteristics. Treble, especially for non-treble lovers can get on the hot side. Even I found it a bit hot from time to time. It’s a nice combination but I still prefer it on tubes because the mid-section can really use that extra warmth. Nonetheless, if you like the T90’s sound when used in combination with a solid state amplifier, I am sure you will love this setup. With the T70 I have always had a love-hate relationship, for my personal taste it is a bit too analytic. Sure the A20 gives that extra bit of bass the T70 misses (imo) but I just can’t get used to this headphone.
Two of my favorite headphones (I have way too many) are the Philips L2, which I loved with the Duet amp, and the Sennheiser HD650, the King. With the last one, music comes effortless and fast. I find it to be a brilliant match with the A20 amplifier: dynamic, neutral, fast, musical, a good amount of tight bass. It’s so enjoyable, like if the A20 was made for this Sennheiser. The low impedance Philips L2 gets great bass from the A20. The L2 is very easy to drive and unfortunately I don’t find the A20 to add a lot extra to its sound besides the bass. The pairing between the Duet and the L2 was much better and that leaves me wondering how it will work with Beyer’s own 32ohm DT770 AE.
Well the magic that isn’t there with the L2 definitely is there with Beyer’s DT770AE. The AE version of the DT770 already has good bass and mids as we’ve reported before. With the A20 you get even more bass on the AE and thick mids, the treble section however is far behind. It’s basically the typical AE sound with extra bass. A fun combination that’s a little less audiophile sounding however.
Of course I had to try an orthodynamic headphone with the A20 so I chose the popular LCD-2. The A20 has enough power to drive it and the sound is ok but I do prefer the LCD-2 on the “bigger” more powerful solid state amps like the Violectric V200, Burson or Bakoon as the sound quality with these amps is higher than the A20’s quality (and so is the price). The A20 does ok with the orthos but it isn’t the best match for the planar technology headphones. Sound is less dynamic and resolving but bass is good. So it is ok but the LCD2 can sound much better. Then again, the A20 wasn’t made for them either so you shouldn’t really focus on this part.
The A20 is not really supposed to be used with custom IEMs but while I’m at it I’ll just add them to the list. The Cosmic Ears BA4 is dead silent when connected and there is no hiss and no channel imbalance. Be careful with the volume dial however cause it will get loud fast. I like how the A20 performs with the BA4, a bit of extra bass and a very neutral sound. The combination of the BA4 with the Cypher Labs Duet (and even the Theorem) is better however. So this combo can be good but there is better. Hmm, it seems the Teutonic A20 just prefers its fellow countrymen 😉
The Final Verdict
I really like this amplifier. As I said I never expected it to be this good and enjoyable, especially for its price. It made me rediscover some of my headphones like the HD650 and T90 which I am used to listening to on tube amps. For dynamic headphones, this Beyerdynamic amplifier gets the “Headfonia Approved” label for sure. A musical affordable solid state amp with a high fun factor and a quality sound: what’s not to like? Mid-Fi doesn’t get any better than this.
The Beyerdynamic A20 is available for €499/$679 directly from Beyerdynamic or via one of their official retailers. If you’re looking for a good sounding, small desktop amp for your dynamic headphones I absolutely can recommend you this one. I’m sure you’ll enjoy it as much as I do.