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Luxman SQ-N150 Review (Tube Amplifier)

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 229 75.1%
  • 2. Not terrible (postman panther)

    Votes: 55 18.0%
  • 3. Fine (happy panther)

    Votes: 8 2.6%
  • 4. Great (golfing panther)

    Votes: 13 4.3%

  • Total voters
    305

SIY

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Some prefer a bit of 2nd, 3rd harmonic tho most here don't.
I keep seeing this claimed but haven't seen any actual evidence that it's true when the sound waves hit the eardrums. :cool:
 

TCD333

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Come on... this is Luxman. They know more about audio component design than anyone commenting on this thread, IMO.

As I stated before, I am convinced they designed this as a low volume offering for those who prefer this kind of thing to pair with very high efficiency speakers and achieve a certain pleasing sound for certain types of music. Those people exist. It's NOT supposed to measure in any way like solid state, it is the complete opposite.

And as I said, it is totally not something I'd even consider, but I have a friend whose conviction is tubes and Devoré speakers... and it sound pretty seductive if you listen to Chopin. On his system, Pogorelich's Chopin sounds drippingly emotional, on mine it sounds like a piano competition performance.

It's clearly not a device to please the ASR crowd and it was woefully mismatched in the listening test with the speakers used, really, come on.

And everybody talks about tube amps that measure better and just one was mentioned in the discussion (at least as far I saw saw) and that thing is probably a fire hazard.

Remember these days devices have to pass homologations, which hampers the envelope for classic tube designs.

PS: I. never have and I never will own a tube amp. Their harmonic distortion does not work for me given my wide ranging music taste, but even as a sceptic I will once. more say... with the right pairing, for the right music... they are a different experience... but one you should explore sometime. Feel free to smell some exotic roses when you're able to detach yourself from thinking about measurements while you actually should just chill and listen to music.
100% on all points. However, I don't think many here will understand where you are coming from.
 

Bleib

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I keep seeing this claimed but haven't seen any actual evidence that it's true when the sound waves hit the eardrums. :cool:
On a Swedish computer forum there are some folks who want tubes for headphones for instance. They certainly exist.
I myself naturally lean towards as clean as possible (and wish loudspeakers and headphones could match the electronics)
 

dfuller

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How?
20 clean watts?
Well, assuming one severely overvolts them and runs them in pentode mode... That could work. Guitar amps push a pair to 20 watts pretty regularly, albeit at about 5% THD and running at the better part of 400V Ua and Ug2. With a bit more feedback and some more careful circuit design, quite possible.
Anecdote: I ran JJ EL84 in my Red Light District amp at 13.75W plate + screen dissipation for a decade before replacing them. They were still working so it was really more of PM.
Chalk one up against the "They don't build 'em like they used to, buy NOS!" crowd. That's near guitar amp levels of abuse. (though, as you noted further in, if you're running at low screen voltage then you're less likely to have them blow up on you...)
One thing I noticed with JJ power tubes is their quality isn't always consistent.
Very true, it's why I tend to buy them from Eurotubes because they have a good relationship with JJ (meaning they get the factory's best testing) and actually test their tubes on good quality testing apparatuses (IIRC, a few Amplitrex AT1000s and some modern computerized curve tracer, I think a RoeTest?).
Marshall for a while sent over their amps to USA with 6550's back in the 80's because the EL34's weren't as good as they once were and typically didn't make it past the warranty period.
This was a requirement of their US distributor. 6550s are much tougher than EL34s - even in the 60s and 70s when Mullard et al were still producing top quality stuff, GE. Sylvania, and Tung-Sol 6550s were basically the tubes that would survive anything. The EL34s were getting shaken about in shipping and because they were relatively lightly built by comparison, they would have a lot of in-warranty failures. The 6550s... well, they didn't!
 

levimax

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On a Swedish computer forum there are some folks who want tubes for headphones for instance. They certainly exist.
I myself naturally lean towards as clean as possible (and wish loudspeakers and headphones could match the electronics)
Lots of people claim they can hear a difference but as @SIY pointed out they seldom if ever do actual level matched blind tests to see if they can actually hear any difference in a controlled setting. You would think if there really was a difference that after all these years someone would have done some blind testing showing people could reliably hear a difference but I have never seen one. I went to the trouble of doing a blind level matched test and I could not hear any difference between a 60 SINAD tube amp and a 100 SINAD SS amp.
 

Ken Tajalli

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Well, assuming one severely overvolts them and runs them in pentode mode... That could work. Guitar amps push a pair to 20 watts pretty regularly, albeit at about 5% THD and running at the better part of 400V Ua and Ug2. With a bit more feedback and some more careful circuit design, quite possible.
Hence why I put the CLEAN clause in my question.
Unless one gets into abuse levels and or class B operation, about 12/15W is max.
I ended up not liking the pentode mode sound (even though it was clean).
Had no UL transformers, so I settled for Triode mode at about 6W!
It was enough , for my office.
 

DonH56

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Luxman does not have the only good designers, tube or otherwise, on the planet. I would not underestimate the ability and experience of knowledgeable ASR members posting in this thread. Luxman designers plug their tubes in one at a time just like the rest of us... It may well be that Luxman engineers were constrained by marketing or accounting, but there are clearly some issues that people here have highlighted. One of the great things about ASR is that we have some truly exceptional technical members who take a back seat to nobody.
 

brk

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100% on all points. However, I don't think many here will understand where you are coming from
Come on... this is Luxman. They know more about audio component design than anyone commenting on this thread, IMO.

As I stated before, I am convinced they designed this as a low volume offering for those who prefer this kind of thing to pair with very high efficiency speakers and achieve a certain pleasing sound for certain types of music. Those people exist. It's NOT supposed to measure in any way like solid state, it is the complete opposite.

And as I said, it is totally not something I'd even consider, but I have a friend whose conviction is tubes and Devoré speakers... and it sound pretty seductive if you listen to Chopin. On his system, Pogorelich's Chopin sounds drippingly emotional, on mine it sounds like a piano competition performance.

It's clearly not a device to please the ASR crowd and it was woefully mismatched in the listening test with the speakers used, really, come on.

And everybody talks about tube amps that measure better and just one was mentioned in the discussion (at least as far I saw saw) and that thing is probably a fire hazard.

Remember these days devices have to pass homologations, which hampers the envelope for classic tube designs.

PS: I. never have and I never will own a tube amp. Their harmonic distortion does not work for me given my wide ranging music taste, but even as a sceptic I will once. more say... with the right pairing, for the right music... they are a different experience... but one you should explore sometime. Feel free to smell some exotic roses when you're able to detach yourself from thinking about measurements while you actually should just chill and listen to music.

That’s exactly right. They also make great high power solid state amps that measure really well and include real tone controls… and phono cartridges and preamps. They know what they are doing and make a wide range of stuff for different set-ups and tastes.
 

pseudoid

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Come on... this is Luxman. They know more about audio component design than anyone commenting on this thread, IMO.
But it seems as though they ignored the 600pound gorilla, while obsessing over the looks.
202206_LuxmanNoise.jpg

I hate to put it this bluntly but NASA also knew what they were doing w/the STS-107, too... yet, they found comfort in learning from such a tragic situation w/o excuses.
 

MakeMineVinyl

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But it seems as though they ignored the 600pound gorilla, while obsessing over the looks.
View attachment 214127
I hate to put it this bluntly but NASA also knew what they were doing w/the STS-107, too... yet, they found comfort in learning from such a tragic situation w/o excuses.
Power supply noise (if you're referring to that) is difficult to completely suppress in a tube amplifier.
 

Ken Tajalli

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But it seems as though they ignored the 600pound gorilla, while obsessing over the looks.
View attachment 214127
I hate to put it this bluntly but NASA also knew what they were doing w/the STS-107, too... yet, they found comfort in learning from such a tragic situation w/o excuses.
I am thinking this could be a faulty unit!
Circuit is not flawed, could be better, but not flawed.
A balanced power stage, with Triode splitter/driver should not have that much 2nd harmonic distortion.
Excessive PSU noise also points to an issue with the balancing, PSU noise rejection is out of wack.
A possibility!
 

MAB

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Come on... this is Luxman. They know more about audio component design than anyone commenting on this thread, IMO.
Possibly not. Have you read reviews of their other equipment? There are warning signs that today's Luxman has no resemblance to old Luxman, and are not representative of good engineering practices that we all hope for.

For instance, their $10k integrated solid state amplifier reviewed and measured here:
A few things stand out. This unit has no dedicated headphone amp, instead they use a resistor drop from the power amp outputs which is a hack, and will have poor performance with lots of headphones, and mediocre with the rest. This is bit deceptive since the marketing literature says each subsystem is best in class, no expense spared, etc... The headphone feature should have been omitted from the product if this was the solution available at the $10k price point.
Channel balance on the tested unit is mediocre. RIAA is mismatched between channels above 2kHz is not good either.
These are all likely below audible, except for the frequency response changes with some headphones.
You see where I am going...
I actually think some people on this thread may know quite a bit more about component design and product architecture than modern day Luxman.

It's clearly not a device to please the ASR crowd and it was woefully mismatched in the listening test with the speakers used, really, come on.
I think the SQ-N150 measurements say it is not pleasing to any crowd. It has some really odd problems that have been discussed at length, and is likely to demonstrate those on any speaker combo. Some of the issues will be more evident the higher the sensitivity.
And everybody talks about tube amps that measure better and just one was mentioned in the discussion (at least as far I saw saw) and that thing is probably a fire hazard.
The point of that post was to show a decades old Dynaco, designed by competent engineers, does spec better than this really fancy thing here. This is disrespectful to the person who posted it!!! And misses the poster's point: junk outperforms this amp
PS: I. never have and I never will own a tube amp. Their harmonic distortion does not work for me given my wide ranging music taste, but even as a sceptic I will once. more say... with the right pairing, for the right music... they are a different experience... but one you should explore sometime. Feel free to smell some exotic roses when you're able to detach yourself from thinking about measurements while you actually should just chill and listen to music.
And, if you got the tube itch, this would likely not be the amp to buy. That's all that is being said here.
 
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MakeMineVinyl

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The point of that post was to show a decades old Dynaco, designed by competent engineers, does spec better than this really fancy thing here. This is disrespectful to the person who posted it!!! And misses the posters point: junk outperforms this amp
I have 5 other tube amps of older vintage I could have added to the testing in that post (two Dynaco MKIIIs, McIntosh MC-240, Audio Research D-76A, Dynaco ST-70). The problem is that they are all much heavier than the little Dynaco SCA-35, and there's only so much physical effort I'm willing to expend to prove a point. :)

PS: None have caught fire yet. :facepalm:
 

pablolie

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Possibly not. Have you read reviews of their other equipment? There are warning signs that today's Luxman has no resemblance to old Luxman, and are not representative of good engineering practices that we all hope for.

For instance, their $10k integrated solid state amplifier reviewed and measured here:

That is why Luxman offers several amplifiers. Pick what you value as an audio aficionado. You imply the unit failed the measurements, but it didn't. The last paragraph shows that. It seems to be another one of their "traditionalist" solid state offerings. Yeah the headphone amp seems to be compromised. Deal breaker for me. The 150W "under no load" in the specs also turns me off. Most of Luxman's current solid-state offering fall into that Class A-like value prop.

I haven't owned Luxman in a long time, and their current Class A-ish direction is a bit of a turn off for me. In any case, as I stated, big cumbersome amps are no my cup of tea these days.

Guys - I am not in any way defending the performance of this tube amp. Like I said, I voted "poor". But I get why a brand like Luxman caters to audiences with specific preferences, irrational and self-defeating as they may seem to you. This forum is quick to dismiss personal preference when the (limited yet representative) measurement catalog doesn't seem to support such a choice. I am more yang about that. I don't tell people what they should pick or shouldn't. My only reason to post on this is, as mentioned, that I have listened to the combo of a tube amp and high efficiency speakers at a friend's place repeatedly, and it has some magic for certain types of music, and I'd encourage others to not dismiss the effect of harmonics etc at times.
 
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SIY

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Guys - I am not in any way defending the performance of this tube amp. Like I said, I voted "poor". But I get why a brand like Luxman caters to audiences with specific preferences, irrational and self-defeating as they may seem to you. This forum is quick to dismiss personal preference when the (limited yet representative) measurement catalog doesn't seem to support such a choice. I am more yang about that. I don't tell people what they should pick or shouldn't. My only reason to post on this is, as mentioned, that I have listened to the combo of a tube amp and high efficiency speakers at a friend's place repeatedly, and it has some magic for certain types of music, and I'd encourage others to not dismiss the effect of harmonics etc at times.
Problem is not preference, it's that within the design paradigm, this is implemented poorly.
 

pablolie

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Problem is not preference, it's that within the design paradigm, this is implemented poorly.
Not sure I agree. Tell me of another tube amp in the 10W game that measures better. :) This is clearly designed for a narrow audience. Many tube designs are fake tube designs that kinda keep tubes in the preamp section but really amp stuff up in solid state. It's cheaper and makes it easier to pass homologation.
 

pseudoid

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That is why Luxman offers several amplifiers. Pick what you value as an audio aficionado.
Do any of their models feature a "Dial-a-THD" knob?:facepalm:
 

pablolie

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Do any of their models feature a "Dial-a-THD" knob?:facepalm:
Nor do I know nor do I care. Luxman is there and they have a loyal (and seemingly affluent) customer base it seems. I have clearly stated they are not my pick these days. But remember they were GONE ... then came back to life and probably researched their market niche, seemingly well, because they are still around.
 
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