Tube Review!
I've been wanting to do a review of all my tubes, but wanted to wait until i had enough tubes. Anyway, these are my thoughts on the tubes i own. My audio chain is: PC > Foobar2k >Aune T1 > headphones.
I've had the T1 for nearly 2 years now, and have experimented with tubes since last year. The first year or so of owning the T1, i was using the stock tube as i basically didn't find any faults in it. I liked the sound as is. However, after getting my first tube (Amperex 7308) and seeing how much of a difference it can make, the tube fever began. And my wallet only got thinner over time. Please keep in mind that these are my own, subjective thoughts that i write based on what i hear through my own, imperfect ears.
The headphones used for this evaluation are:
-Beyerdynamic DT880 250ohm
-M-Audio Q40 with HM5 pleather pads (thick version) and a red V-Moda cable
-Sony MDR MA900
This is my tube collection:
1. Electro-Harmonix 6922 (the stock tube): (Around $20)
Not a lot of wrong this tube does to be honest. I find it to be a great stock tube and i think Aune made the right choice in picking this as the stock tube. From my findings, this tube slightly V-shaped. Bass extension is very deep, however the bass is loose. This is particularly noticed when you compare it to better tubes. There is also a nice amount of midbass punch. Mids, well, they're interesting. I have found vocals to have a "raw" feeling to them. They just don't sound that smooth or refined. They're slightly behind the bass and treble, but not by much (tiny amount). The highs are slightly etched (especially the very upper regions), i would say that the treble is decent but can somewhat sound splashy and uncontrolled at times. Soundstage is wide, imaging is mediocre.
Overall a good tube, but nothing really stands out or makes you dance.
2. USSR 6N23P NOS, late 60's or early 70's production. *NOT the Voshkod version* ($8)
Very dull and lifeless tube. Bass is soft and lacks extension. Highs are rolled off. The mids, though, are somewhat decent. Female vocals sound nice on this tube. This is also partly due to the fact that it has a small soundstage. This makes for a very intimate sound experience. Detail, clarity, transparency of this tube are weak in my opinion. Overall: Cheap. Decent mids. Everything else is bad. Avoid this tube.
3. Amperex 7308 NOS: ($50-90), I got it for $65.
What can i say that hasn't already been said. This is the benchmark tube in my collection, and its also my favorite. There is honestly not a thing this does wrong. I've had it for a year now and i thought that as time goes on im going to notice something that sucks about it, but in all honesty there isn't. Detail, clarity, transparency? Top-notch. The clarity is especially amazing here. Bass goes low. Really low. And it stays tight. Its not the bassiest tube out there but it does pack some nice punch. Mids are astonishing.
Ultra-smooth. Hold on, let me say that again.
Smooth. Extremely clear with a very slight hint of warmth that makes them that much more musical. Treble is also clean and clear. Nothing rolled off here. Soundstage is also the widest out of my tubes, and imaging is great. I have been listening to Hans Zimmer's "Rush" movie official soundtrack on this tube, coupled with my MA900's which already have a wide soundstage, the experience was sublime.
Overall: Neutral tube with a slight hint of warmth, and superb sonic abilities. Expensive, but worth it in my opinion. Recommended!
4. Amperex 6DJ8 (Or is it?) Small Halo Getter NOS, made in Holland. ($20)
I thought i stumbled upon a gem when i saw a 6DJ8 Amperex for $20, but then i realized this might actually be fake. Firstly, the writing on it actually says "Electron United" in yellow. After reading more and more about tubes, i learned that genuine Amperex tubes have gold pins, a circle in the middle of the pins, and 4 lines that start on the top of the tube. This particular tube does not have the circle, and it doesn't have gold pins. Most of you guys here are more knowledgeable at identifying tubes, so please tell me what exactly this tube is.
Anyway, onto the sound: This thing is MUSICAL. Very, very warm tube. The bass is softer than what i would prefer and the subbass is not as present, but nevertheless it has good quality bass. Mids are very musical and warm. Guitars and stringed instruments sound wonderful on this tube. The mids are also very slightly forward, but they're extremely smooth and never sound "raw" like in the stock tube for example. Treble takes a step back here. This definitely has the most subdued highs of all my tubes. But i like that actually. The soundstage here is almost as wide as the 7308, but not quite. Imaging is only decent. Technical abilities such as clarity, detail and transparency are good, but they're not as good as the 7308 for example. Still close to be honest. Again, this is an extremely musical tube. You plug it in and you simply won't care if its not technically superior to your other tubes. This is the kind of tube that you would not mind listening to for the entire day. Its impossible to hate this tube.
Overall: Warm and musical. Well worth the price i payed for. Recommended!
5. Siemens ECC88 NOS ($23) (thanks
@mikoss for recommending this tube!)
I was looking for a tube that does electronic music well and ended up getting this. So, is it any good? Yes. Absolutely. First thing i want to mention is the level of detail this thing has. I was shocked. This thing costs as much as makes no difference half the price of my Amperex 7308 and has the same amount of detail. And the 7308 is already hyper-detailed to my ears. Both those tubes are the most detailed in my collection. This tube is fun! The bass extension is deep and subbass has got a lot of presence. Bass quality is very good, bass stays tight and controlled. Maybe there's a tiny, and i mean tiny bit of looseness but that may be my imagination. This tube had the impact i was searching for in the bass. The mids are withdrawn and sound a bit thin compared to say the 6dj8 Amperex. However, they are clear and detailed. The highs have slightly more presence than neutral, but the treble is not that fatiguing. Unlike the stock tube, the treble here (although etched) is clean and not splashy. Soundstage is only decent, however the imaging is extremely good. This tube has the best imaging in my collection. Definitely a keeper.
Overall: Very fun tube. Boosted bass and highs, excels with electronic. Recommended!
6. GE Smokie 6DJ8 NOS ($18)
First of all, can i say this tube looks like nobody's business when plugged in to the T1. It honestly looks menacing and badass. I've never enjoyed looking at a tube this much before.
In terms of sound, this is definitely one of the budget kings. Has a very enjoyable and fun sound. This thing has strong midbass. Probably the most powerful midbass of all my tubes. Subbass extension is also good. Mids are not forward nor recessed (or at least to my ears) they are right where they should be. The mids are meaty and thicker in comparison to they Siemens. Actually the sound as a whole feels more meaty and authoritative. The highs are also very nice. They are slightly laid back (very slightly) which makes them work for brighter headphones. This tube has great clarity and transparency for its price.
Overall: A budget king. Bassy without making the rest of the frequency suffer. Recommended!
These have been my thoughts on the different tubes i own. Again, this is a subjective review. Your findings and opinions may vary
.