More UltraLinear praise

After some hesitating deliberation for choosing between the Solo SRGII and UltraLinear, I finally listened to Graham wise advices and decided to purchase the Graham Slee UltraLinear.

I received it around christmas last year, and have been enjoying it a lot since then.

My playback system is composed of the Lavry DA11 connected to a Macbook through an asynch USB to SPDIF converter Audiophilleo2. I use Pure Music as exclusive software playback. The Graham Slee Ultra Linear is connected to the Lavry through a pair of Oyaide QAC-212 interconnects (Hitachi Long Cristal OFC). Power line is dedicated for audio, and a PS Audio Duet Center is used for power conditionning. Power cables are Furutech OCC DIY for the Graham Slee amp as well as for the PS Audio Duet Center to the wall. The Lavry is powered by a Shunyata Research Sidewinder CX. I shall add that both amp and DAC are now resting on small Ayre Myrtle wood blocks for vibration control.

My headphone of reference are the atypical DT48A. For those who don't know them and have some interest, you can find here a link to the review I wrote on Head-Fi. I just happen to love those headphones but understand perfectly that they can be unappealing for many.

Before entering into the more subjective evaluation part, I wanted to answer my own previous question regarding the possible hiss when using my ultra sensitive DT48A with the Graham Slee UltraLinear. With 5 ohms and 110dB/mw, and if I am not mistaken (using this formula I found dB/mW = dB/V - 30 + 10*log(R) ), this translates to 133dB/V, which is indeed very sensitive for a headphone, on par with the most sensitive IEM out there.

Well, unfortunaltely, yes, I could hear some background hiss, quite noticeable especially during quiet moments of music. However, I have been listening to the UltraLinear and DT48A combo during those last 4 months without any frustration, amazingly... Yes, there was noise, but there was also something else grabbing me at the same time, and that noise was actually never messing or interfering with the music, quite unobtrusive. I finally have had soldered recently a pair of very high quality 75 ohms Z foil radial resistors directly into the 1/4" jack of my DT48A, and the hiss is now gone for good, which leaves me with pure bliss of music.

I don't have lot of experience with headphone amplifiers, and I have only owned a handfull of those (Rudistor RP5.1, Rudistor NX-33, Creek OBH21, Little Dot MKIII, Little Dot I+) and still own a Creek OBH11 and Meier Stepdance at the moment, so please be gentle with me and consider my relatively limited experience with amplifiers when reading my impressions.

Still, I could say right from the start that the Graham UltraLinear has brought something new to the listening experience as compared to all other headphone amplifiers I heard before. They certainly was a burn in phase for the UltraLinear and it is actually the first time I noticed it so apparently with a piece of equipment. At some point (not sure how many hours but maybe somewhere between 20 and 50 hours), the sound became very hollow and dull, overly soft, before finally stabilizing and offering its quite unique sonic characteristics.

And what does set the UltraLinear apart of other headphone amplifiers is for me its ability to connect me with the music. I don't quite know how to describe it, but the UltraLinear seem to respect the timing of the music in such a cocherent way that the music just starts flowing freely, breathing again and never constrained. I really don't know if this is linked to this "phase linearity" trick, but it indeed feels as if higher tones and harmonics present in the recording are perfectly portrayed and respecting the timing of the music. This is especially apparent in the lows and highs frequencies to me. The high frequencies are completely free of any glare or harshness, but still vivid and lightfull, delicious in their extension but never out of place. The lows appear as breathing again, not congested and restricted, not sounding artifically fast or dry (ouch the Meier Stepdance). It really gives the sensation of a more powerfull foundation to the music but it is not accentuated or emphasized, but rather sounding full and melodious again. Trully remarkable.

Those impressions are especially true with the DT48A. The Fostex T50Rp I also own for example do respond in a similar way but to a lesser degree as they already have a rather smooth own sound character.

The level of resolution of the UltraLinear I feel is excellent, just plenty enough to look into the different recordings, ambiances, etc...

Sincerely, I have a hard time critising any aspect of the music reproduction through the UltraLinear. It has really become an essential part of my system which I feel is now completed, allowing me to just relax and enjoy as much music as I can (but still much less than I would like).

Thank you Tg,