After going from motherboard onboard sound to external DAC (schiit modi). I noticed an improvement in clarity across the board, but vocals in particular sounded flat, and the soundstage was very narrow. I don't know if this was because I was using a DAC designed for headphones, with a speaker amp. My vinyl flac recordings were much better than my cd flac files regarding vocals. So I picked up one of these to play around with, and see if I could improve things.
It arrived from China in just 11 days. Pretty impressive since at time of purchase it said it could take up to a month to ship. Requires some assembly, but pretty straight forward despite lack of instructions. Mine says version 1.3 on it, not 1.2. This thing is extremely light, so you'll have to really mess with your cables to get it to sit still.
With the included 6j1 tubes, right away I noticed the soundstage was much improved, the sweet spot wasn't quite so narrow anymore. But the sound clarity was several steps down, especially the bass. It was very loose and muddy. I let it play for around 5 hours, and just wasn't noticing any improvement, and couldn't stand the sound anymore. So I swapped in some Tung Sol 6ak5 I had. Wow, vocals suddenly had so much more authority. The sound was really pleasing now. I can't wait to see what other tubes are like. I've got GE jan5654, Voskhod 6zh1p-ev, and Sylvania 6ak5 on the way.
Update: I've got about 20 hours on the amp with the Tung Sol tubes now. It's obvious this thing is adding distortion of some sort to the music. Similar to the kind of distortion going from lossless to mp3. On some types of music, in particular female vocals. It sounds really good. But on some male vocals, my subwoofer is reacting to the vocals, which sounds like when a Mic that isn't dialed in right. I really hate this thing for some songs, but love it for others. I've never played with tubes before. But I'm guessing this is just the nature of the beast. I will be trying out other tubes as I get them. I also have plans to rig up some mechanical switches that let me go from using this, to not using this on the fly.
Update 2: Tried some GE Jan5654 tubes. Must tighter and more detailed than the Tung Sols. Really like the sound of these tubes. Noticed I'm getting getting some random clicks and squeals with this preamp, in the right channel only. Can only hear the ticks close up, like ears inches away and music off. The squeals don't happen often, but you do notice them. I think it's emi, since I can make it happen sometimes with mouse movements and scrolling. Tried moving it around, and plugging it in elsewhere including directly into outlet. Have not been able to get rid of it. I may try to shield the case and see how that turns out.
Update 3: OK, this is strange. The included adapter is a 18v ac-ac. I tried a HP 18.5v, 3.5a laptop brick I had laying around on it. It not only works, but the clicks are gone, and the squeals are significantly reduced to the point they're barely audible. The tubes are glowing significantly brighter though, not sure if there will be long term damage.
Update 4: Tracked down source of clicks and squeals to interference from smartphone. Completely eliminated, by keeping phone away, or going into airplane mode. Currently trying out some Zenith 6ak5 tubes on it.
It arrived from China in just 11 days. Pretty impressive since at time of purchase it said it could take up to a month to ship. Requires some assembly, but pretty straight forward despite lack of instructions. Mine says version 1.3 on it, not 1.2. This thing is extremely light, so you'll have to really mess with your cables to get it to sit still.
With the included 6j1 tubes, right away I noticed the soundstage was much improved, the sweet spot wasn't quite so narrow anymore. But the sound clarity was several steps down, especially the bass. It was very loose and muddy. I let it play for around 5 hours, and just wasn't noticing any improvement, and couldn't stand the sound anymore. So I swapped in some Tung Sol 6ak5 I had. Wow, vocals suddenly had so much more authority. The sound was really pleasing now. I can't wait to see what other tubes are like. I've got GE jan5654, Voskhod 6zh1p-ev, and Sylvania 6ak5 on the way.
Update: I've got about 20 hours on the amp with the Tung Sol tubes now. It's obvious this thing is adding distortion of some sort to the music. Similar to the kind of distortion going from lossless to mp3. On some types of music, in particular female vocals. It sounds really good. But on some male vocals, my subwoofer is reacting to the vocals, which sounds like when a Mic that isn't dialed in right. I really hate this thing for some songs, but love it for others. I've never played with tubes before. But I'm guessing this is just the nature of the beast. I will be trying out other tubes as I get them. I also have plans to rig up some mechanical switches that let me go from using this, to not using this on the fly.
Update 2: Tried some GE Jan5654 tubes. Must tighter and more detailed than the Tung Sols. Really like the sound of these tubes. Noticed I'm getting getting some random clicks and squeals with this preamp, in the right channel only. Can only hear the ticks close up, like ears inches away and music off. The squeals don't happen often, but you do notice them. I think it's emi, since I can make it happen sometimes with mouse movements and scrolling. Tried moving it around, and plugging it in elsewhere including directly into outlet. Have not been able to get rid of it. I may try to shield the case and see how that turns out.
Update 3: OK, this is strange. The included adapter is a 18v ac-ac. I tried a HP 18.5v, 3.5a laptop brick I had laying around on it. It not only works, but the clicks are gone, and the squeals are significantly reduced to the point they're barely audible. The tubes are glowing significantly brighter though, not sure if there will be long term damage.
Update 4: Tracked down source of clicks and squeals to interference from smartphone. Completely eliminated, by keeping phone away, or going into airplane mode. Currently trying out some Zenith 6ak5 tubes on it.
