Right away if you want to know whether this amp sounds like how a tube amp is infamous to sound like in short BA-10 sounds like a hybrid amp when used only as a single ended in. If you truly want to get the tube amp sound, you know the expansive soundstage, smooth high, thick lush mids and an engaging textured bass you can only get this sound if you use balance in/out. To me balance in and single ended out sound the same as single ended in and balance out. I only got the sound I wanted using both the input and output in balance format.
I initially hoped to use the BA-10 paired with Sony WM1A using its 4.4mm Pentaconn connection however the results wasn’t stellar at all. I think it simply doesn’t offer that much current out however offers plenty of voltage out. I happened to order a custom AK cable to use with AK70 and to my surprise AK70 pairing with its 2.4 VRM offered the current BA-10 seems to need. I also used the Onkyo DP-X1 to test scalability of the BA-10.
Now for the purpose of this review I used the Astell and Kern AK70 as a balance source feeding the HIROSE balance input of OAK. Below is the list of the IEM I selected to use in my review:
• AKG K3003
• JVC FW-01 using Sony MUC-M12SM2 cable
• Cardas EM5813
• Dita Truth
• Fitear F111 using Jaben Spiral Strand balance cable
• ATH CKR10
• Inear stagediver SD2s using Brise audio STD001 AK cable.
Single ended the OAK is fairly neutral. If one were to listen to it initially without knowing anything about the design of BA-10 they would think it is just a warmish solid-state amplifier.
It is just slightly north of neutral using single ended out, offering a moderate soundstage, relatively forward vocal. In terms of speed of this amp it is able to compare to its solid-state competitor well however using single ended those complex orchestra passages can sound congested.
Using my Cardas EM5813, which has quiet thick midrange I tested whether the thickness of midrange of EM5813 will be enhanced, which for me would have been a bad thing and thankfully no significant alteration in sonic characteristic of my Cardas was heard by me.
But change things over to balanced out for me this is where it is all at. Sound becomes smooth, detail stand out better. It feels like the entire soundstage gained an extra 2-meter of space in all dimension and yes the background noise becomes more noticeable at the lowest volume when no music is playing back using my Fitear F111. Annoying? Perhaps if I was listening to amplifiers without music playing, however since I know of no one who use amplifiers for such usage I am sure that will not bother many of us. For me pairing my F111 using the balance out of OAK basically resulted in what felt like an addition of a entire dedicated midrange driver in my F111 without influencing the infamous expansive soundstage of F111.
Similar effect was heard with my SD2s, however I felt improvement in bass and midrange was more noticeable. In terms of background noise the level was so low that it can with all intensive purposes be ignored. What we gain with this pairing is an improvement with an already good midrange detail, somehow making the SD2s more coherent. The vocal gained emotion that wasn’t present before. If I were to pick a favourite pairing this setup would be my most favourite out of all the IEM I tested.
There are two ways this can be test:
1) Does altering the input of BA-10 improve its overall sound performance?
2) Does using balance out of BA-10 improve the sound compared its single ended 3.5mm output?
I answer one with yes and I answer two with a HUGE YES.
I’ve said this before already but I have to say it again in order to get the best of this amp you must use its balance in and balance out.
While I did hear an improvement in resolution and channel separation going from AK70 to DPX1 however going from singled end out to balance out offered so much more improvement that I simply can’t go back to the 3.5mm output after hearing that. Sure improving the sources always helps but the bottle neck will be how you ended up connecting and listening to BA-10.
Oriolus engineers offer a very sensibly priced and solid first attempt into what I think to be a hybrid amplifier made sound as close to tube can without excessive heat production. It offers a taste to those who like to get into tube amplification but who aren’t ready to spend north of 500 USD yet. It is a product that performs much higher than its price point. For its price point and sound there isn’t much I can pick on it except that it requires an external traditional 16 DC volt to power brick and in these day and age that can be cumbersome. Beside that I can’t really find any other fault. Once everything is plugged in no microphonic can be heard, it gets warm but never too hot to touch.