I’m also using Russian tubes (Reflektor 6N3P-DR Matched Pair) instead of the original ones. Same behavior on both… could it be tube bias? The brighter one is also hotter (not surprisingly). Unless we periodically rotate them, this means the right tube will burn out faster than the left, doesn’t it?
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I hadn’t even thought about burn out. You raise a very interesting point. Should we be rotating them monthly? Semi-annually? Annually?
Shane D
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If your Russian tubes are burning identically, then it should have even wear. Are you saying ever since you placed new tubes in, it’s exactly identical?
If, like car tires you have uneven wear, probably have to be replaced more often.
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Now that I look closely, the tubes do burn differently. With the original tubes, the tube on the right burns brighter than the tube on the left.
With my original tubes, the tube on the right had two bright points and the tube on the left had one bright point and one dim/small point.
With the Russian tubes each tube seems to have one bright point and one dim/small point.
Shane D
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I’m getting talked out of buying one of these. It’s probably not a huge deal but I’d like a good first experience with tubes and there have been a few off-putting comments.
Up until now what’s held me back is that it’s often said that it doesn’t sound much like a full on tube amp. Being a hybrid, I suppose that’s a given.
But QC is a big deal for me as well and there have been a few complaints in that regard around the Web other than this one.
$100 isn’t a lot but I live in Canada and the price has jumped to $149 CAD on Amazon.ca, so there’s that too
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I can agree that I end up comparing it more to my solid state amps more often than tubes. Amp sounds good though, more bassy, warm, and less detailed than an Atom, for example, but still impressive.
You could try AliExpress as well, $92 with free shipping to Canada, though it will take a while to get there and you have to trust AliExpress. And of course if you are one that has QC issues it is harder to deal with.
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Thanks for the info. Funny, I just installed the AliExpress app today for a cheap item. I don’t mind waiting; but as you say QC could be a hassle.
I was even balking at an Amazon marketplace purchase direct from the vendor @ the old pric, due to Amazon’s great return policy.
I think Amazon’s generous/easy returns on their own products (non third-party) is what has likely contributed to them taking over the world!
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If you order the Russian tubes for an additional $35.00 in Canuck bucks (including shipping), it does open it up a bit.
I have never heard a full tube, but I was curious. Compared to my SS amp, the hybrid is not as clean and clear. But I guess that’s the idea of tubes right?
I wanted to try a different sound, but I don’t think this was the right way for me.
On the flip side, I have new opamps (Vivid’s) coming for my Burson Fun amp. And in a much more dramatic change of sound I have a Schiit Loki coming in this week. I probably should have bought this instead of the P20.
Shane D
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Again, your concerns are much the same as mine (even after your owning the amp).
I’ve heard very good tube amps, both balanced and SE so am pretty sure if the sound sig I’m looking for.
A balanced LD MKVI+ sounded great as did a DV 337 once they got the QC sirted and eliminated some noise experienced in the earlier production runs
I was just curious & excited to see a balanced tube amp fir around $100, as it seems were many others.
The thing is $100+ towards this one is $100+ less to put towards what I really want.
So I’ll likely pass until I can find a good “used like new” OTL tube amp. Perhaps a Speedball (in spite of the ridiculous name) or an older Woo W6 or balanced LD.
I heard a real nice little ASL tube headphone amp some years ago (sing.end & distributed by Divergent Technologies).
It has a separate power supply and when I heard it they were at the “MKII” version fir about $400 new.
It’s gone up 50% (now $60) for the “MKIII” version but I haven’t tracked down the supposed improvements for the $200 premium.
I don’t know what to think until I look a little diet into the specs for the new one. http://www.divertech.com/aslmgheaddt.html
It’s probably worth a look as it punched well above its weight to my ears. But that was @$400 and there’s some stuff competition now in the $500->$700 range.
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But doesn’t it also depend on your headphones? Mine are all 32 Ohm and so I was led to believe that a full tube amp would no nothing for my Very efficient headphones.
Which is why I tried hybrid.
Shane D
How about the tube amps on MassDrop? Full tube at what seems like pretty reasonable prices.
Shane D
Your headphones will have an effect on what amps are or are not, to a greater or lesser degree, appropriate.
First, you need to know their impedance (measured in ohms). Low impedance (generally considered to be about 100 ohms or less) headphones generally do not work well with output-transformer-less (OTL) pure-tube amplifiers (e.g. a Bottlehead Crack or Woo WA3). However, they work just fine with transformer-coupled pure-tube amplifiers like the WA6 or tube-hybrids that have a solid-state output stage (most hybrids).
High impedance headphones (from about 100 ohms and up, but mostly centering around 300 ohms) work fine with pretty much any amplifier topology, provided it has the necessary voltage swing to drive them (pretty much anything on the desktop will be fine in this regard).
Note that efficiency is not about impedance (it is not measured in ohms). Efficiency with headphones is measured in terms of how much power (dB SPL/mW) or voltage (dB SPL/V) is required to reach a certain output level. This, in conjunction with the impedance of your headphones, can be used to determine how much current and voltage is required to properly drive your headphones.
Bear in mind that such calculations and specifications are generally made using a 1 kHz test tone. One effect of this is that the computed power requirements tend to underestimate, often significantly, how much current is required to play loud, deep, bass notes. A headphone that is hitting 120 dB at 1 kHz on 100mw of power might require as much as 5-10x that to play a 20 Hz tone cleanly at the same amplitude.
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Thanks for the education. I had been eyeing models like the Dark Voice and various LD’s, but according to the interwebs these wouldn’t do anything with my 32 Ohm 'phones.
I have also read that tube amps accomplish their magic by distorting the sound. I am not sure that I want that. The P20 is certainly not as clear and crisp as my SS amp.
I love variety, but I can’t afford to have many different amps sitting around, based on headphone match and my mood. I have opamps coming for my other amp, but I suspect the differences are going to be very subtle.
I am hoping that the Schiit Loki might be what I am looking for. Just keep one amp, but be able to change the sound signature depending on the headphone, the music or my mood.
I don’t want to disparage the P20, but I don’t think it will finish 2019 in my home.
I signed up to request the THX 789 just for giggles. I probably won’t even he able to get it until 2020.
Shane D
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They’d do something … assuming they’re well enough built to tolerate a low-impedance load like that … but that “something” is likely to be “screw up the frequency response, especially at the low-end”. And that’s because they’re OTL designs that work best with higher impedance cans.
There’s a huge “that depends” caveat with that statement …
Most, especially low-cost, tube amps do add a fair amount of harmonic distortion (sometimes by design, sometimes by lack of engineering). But they don’t have to be designed/built that way.
In fact, a simple, SET-based OTL tube amp will often be more linear with less distortion than a similarly simple transistor-based design. Where the solid-state designs score is that you can use many more parts, and a much more complicated design, to get around the issues with poor gain linearity/matching, and still do it at far lower cost than for a simple, pure-tube, design.
The state of the market for tube amps is such that market-desire pushes most to having more distortion to “get that tube sound” than is necessary. And the very high-performing tube amps, which don’t go down that path, are extremely expensive.
If they make a difference at all, it is because they, also, are exhibiting different levels of distortion and/or noise. I don’t think I’ve ever come across one of the “discrete-parts op-amp” packages that didn’t measure worse than the monolithic IC packages for the same design. And most of the alternate parts if you stick with monolithic ICs don’t measure differently enough that there should be any audible change.
People swear by them though.
It’ll change the tonal response/balance of your system (which is, in itself, a distortion of the original signal). It won’t yield the kind of loosely-controllable harmonic products that tubes do (i.e. it won’t make a solid-state setup sound like tubes), but it will certainly have a highly audible effect on what you play through it - depending on where you set the dials.
I have one in my little demo Schiit-stack, and it’s a great little device - though for formal use in my main rig I use a high-precision studio-grade professional EQ solution, which is a lot more flexible, controllable and precise (also more expensive AND requires a computer somewhere in the chain).
Ultimately, if you want variable tonal profiles/signatures, EQ is the way to do it, either in software or hardware. Using source/amp/headphone matching to tweak tonal response just winds up being imprecise, fiddly, has much smaller effects and is usually way more expensive than is necessary.
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Another thought …
If you want more “tube sound” in a “only when I want it” mode, in an otherwise solid-state chain, another option is to add a tube buffer stage between source and amp. These are usually switchable (i.e. you can bypass them with the flick of a switch) and often allow different settings that effect how much of the “tube flavor” you get (usually by changing the bias settings or levels of feedback).
Quite a few options exist here, ranging in price from maybe $100 to, well, more than you’re ever likely to want to spend!
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“Ultimately, if you want variable tonal profiles/signatures, EQ is the way to do it, either in software or hardware. Using source/amp/headphone matching to tweak tonal response just winds up being imprecise, fiddly, has much smaller effects and is usually way more expensive than is necessary.”
I agree totally and I hope that you are correct. I am still “DAC-less” and so using it will require some creativity in the short term.
Thanks for all the info. I really enjoy all the learning in this hobby.
Shane D
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I have heard the term, but didn’t know what it was. Sounds interesting and I might have a look at that down the road.
Shane D
First, let me add an “amen, brother” to your comment about tube amps that don’t go down the path of trying to give you an exaggerated tube sound being much more expensive. My tube amp experience from long ago (Dynaco PAS-2, twin Mark III) and more recent (friends with Macintosh and/or some Conrad-Johnson equipment) have led me the opposite way - at least for driving speakers. When solid state was not full of IC’s then it’s designs were relatively simple — as indicated in your below quote. And if driven hard they sounded awful. Tubes approaching their limits are much more graceful than solid state.
This kind of evolution is common. But it’s not always easy to visualize. For an analogy, look up History or Watches in the Wikipedia. The key to any good timepiece more complex than a sundial is a precise harmonic oscillator. A weight-driven pendulum is such a device. It has the advantage of good old stable gravity as it’s driving force. But try and figure out a way to make a mobile timepiece . . . And you start to get complicated. (see the Wiki explanations of harmonic oscillator, balance wheel, etc. It gets fascinating).
That’s true. But I really like my Loki, and if you happen to be listening to an MQA stream it throws huge obstacles in the way of trying to EQ your headphones. Or anything else. A quick analog device like the Loki is often just the ticket. And so much less than a dedicated hardware EQ setup downstream after the MQA has rendered it’s audio.
Just a good general purpose quote. I’m tempted to use it as a sig line or Skype mood.
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I only use high or fairly high impedance cans for desktop listening.
The Antique Sound Lab Amp was apparently quite versatile but I also only tried it with Senn 600/650s.
We’ll see.
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This has been a good day for learning. Some great information to soak up from you guys (and gals as appropriate ) as always. Thank you.
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