PrimaLuna Dialogue Seven Tube Amp Review

[DanielT]

Because tube amp circuitry is simple compared to S.S. designs, tubes lend themselves to DIY, since chances of success are higher because of the relative simplicity of the circuits, high voltage concerns notwithstanding. If the attempt is a little off the mark, the amp may still sorta work, albeit poorly. With the S.S. approach, a small error can quickly end in a bunch of melted rock.

Why DIY tube amps? Maybe because someone with knowledge in electronics can and thinks it's fun? Even if the circuitry is simple, it is not possible to get around the fact that good output transformers cost a lot.If you have the ambition to build a decent power tube amp. But a tube pre amp driven in class A should be able to achieve really well (it should be possible to construct a really good one)

Incidentally, OP amp and some resistors and capacitors and then a SOTA pre amp at hardly any cost at all. Assuming a good engineer's construction of course.

 

[Sal1950]

Just the thought of "listening" to cables makes me shudder. The DAC issue is now a non-issue when it comes to performance. There are so many good, completely transparent, mainly Chinese DACs, so you just have to check if the DAC has the desired functions and then buy

I would only interject here, you in no way have to go the China to get a great sounding, fully transparent DAC.
Even Schiit offers some Made in the USA, first quality products that will audibly hang with anything out there.

"All in all, performance remains good enough to provide transparency but short of engineering excellence we like to see in a sea of strong competitors." $229

Schiit Modius E DAC Review

This is a review and detailed measurements of the Schiit Modius E balanced USB DAC. It is on kind loan from a member and costs US $229. The "E" edition swaps the AKM DAC chip for ESS ES9028. See my review of the normal Schiit Modius here. This is a stripped down DAC with no display or remote...

www.audiosciencereview.com

 

[beefkabob]

After trolling through 12 pages of comments in this thread, and many other threads throughout ASR's relentless other threads it appears to me that there is no reliable consensus of opinion for any products vying for supremacy! As someone having deep involvement in the high end scene for more than 50 years, my advice to newbies is check out any gear by actually hearing it in person, before writing the cheque!

Yes. That way, you're more easily suckered.

 

[egellings]

Why DIY tube amps? Maybe because someone with knowledge in electronics can and thinks it's fun? Even if the circuitry is simple, it is not possible to get around the fact that good output transformers cost a lot.If you have the ambition to build a decent power tube amp. But a tube pre amp driven in class A should be able to achieve really well (it should be possible to construct a really good one)

Incidentally, OP amp and some resistors and capacitors and then a SOTA pre amp at hardly any cost at all. Assuming a good engineer's construction of course.

OPTs can be expensive, but they certainly don't cost more than the whole amplifier. You might be able to scavenge some from old broken beyond repair equipment, too. Building you own amplifier can also be fun and maybe educational as well. That could be worth part of the cost of the xfmrs. If you don't do DYI, then buying one would make sense.

 

[Murray A]

Yes. That way, you're more easily suckered.

No, thats a nubie's introduction into the audiophile fantasy world.... TubesR4 Nubes

 

[egellings]

No, thats a nubie's introduction into the audiophile fantasy world.... TubesR4 Nubes

If you like tubes, enjoy; otherwise, simply pass them by.

 

[ahofer]

If you like tubes, enjoy; otherwise, simply pass them by.

Yes. Although it seems like a variable tube simulator would be more practical. A DSP add-in with tunable harmonic distortion (along with EQ).

Announcing beta-test of PKHarmonic VST plugin

As discussed in a separate thread, this is a beta-test of a VST (Windows) plugin to allow you to dial-in an arbitrary amount of harmonic distortion while playing music with your favorite music player. Now you can enjoy that second harmonic without investing many thousands of $$$ into a tube...

www.audiosciencereview.com

(from @pkane )

DCVST Virtual Valve Tube Simulator VST Plug-In

VST Virtual Valve Tube Simulator for VST Platforms.

www.enhancedaudio.com

 

[egellings]

Yes. Although it seems like a variable tube simulator would be more practical. A DSP add-in with tunable harmonic distortion (along with EQ).

Announcing beta-test of PKHarmonic VST plugin

As discussed in a separate thread, this is a beta-test of a VST (Windows) plugin to allow you to dial-in an arbitrary amount of harmonic distortion while playing music with your favorite music player. Now you can enjoy that second harmonic without investing many thousands of $$$ into a tube...

www.audiosciencereview.com

(from @pkane )

DCVST Virtual Valve Tube Simulator VST Plug-In

VST Virtual Valve Tube Simulator for VST Platforms.

www.enhancedaudio.com

I think that part of the draw of tubes is their physical presence. Simulating their sound with DSP would be akin to owning a robot dog, rather than a live one.

 

[ahofer]

I think that part of the draw of tubes is their physical presence. Simulating their sound with DSP would be akin to owning a robot dog, rather than a live one.

I love the analogy, but if tubes provide company akin to a dog there's something wrong with the tube-owner or the tubes.

 

[Sal1950]

I loved the romantic glow of all them big beam power tubes in my monoblocks.
But considering the way the price of power has increased over the last 3 years, I'm glad they're gone.
The AC is sending me to the poor-house as it is.

 

[fpitas]

Hypex plus...
View attachment 311101


Edit:
Tube amp + DIY= Absolutely. Because it's fun. Here for example:

Some measurements of my valve/tube design

Hello all! I am fully aware that most here are not the target audience for valve amplifiers, which is of course completely sensible. However I have seen some interest in the topic, no doubt they have a certain mystique. Because I am mad, I have developed a valve design that I think measures...

audiosciencereview.com

That guy seems to know what he's doing. Refreshing.

 

[fpitas]

I loved the romantic glow of all the big beam power tubes in my monoblocks.
But considering the way the price of power has increased over the last 3 years, I'm glad they're gone.
The AC is sending me to the poor-house as it is.

Still, watching the anodes glow more or less with bass is pretty cool. Or hot. You know what I mean.

 

[egellings]

I love the analogy, but if tubes provide company akin to a dog there's something wrong with the tube-owner or the tubes.

Tubes don't piddle on the carpet, though.

 

[beefkabob]

I think that part of the draw of tubes is their physical presence. Simulating their sound with DSP would be akin to owning a robot dog, rather than a live one.

Well, when it comes to audio reproduction, tubes are dogs, so...

 

[beefkabob]

I do not buy audio gear for its physical presence. I buy it for the sound it makes. SMH.

 

[ahofer]

Tubes don't piddle on the carpet, though.

LOL, no, but they can set fire to the drapes.

 

[Sal1950]

Woof Woof

 

[Thermionics]

Stereophile reviewer should rename himself to Fart Dudley

Cheap shot considering Mr. Dudley passed away a couple of years ago from cancer.

 

[egellings]

Well, when it comes to audio reproduction, tubes are dogs, so...

Nothing's too good for my little Fi-fi; do you understand? N-n-n-nothing. Of course, a tube amp will not beat a Benchmark S.S. one, but the sound can be pleasing, and distortion, with good design, can be kept below audible levels. Why bother with tubes in the first place? I enjoy my DYI circlotrons because of the 'designed & made it muhself' feel, and they do measure well and sound good as well. Plus, they're fiddly, what with bias adjustment pots to be adjusted every so often. If you have a set it & forget it approach to audio or require many zeroes to the right of the decimal point before you see the first non-zero digit in the distortion reading, then such amplifiers are definitely not recommended.

'Circlotron' refers to the output stage design in which tubes & floating power supplies are arranged in a bridge configuration with the OPT across the center of the bridge. As a result, the tubes are all in parallel with the OPT, rather in series with it as would be the case in an ordinary push-pull design, allowing for a 4x reduction in turns ratio in the OPT. This allows for an OPT with excellent performance due to the low turns ratio, and this transformer is patented. So in short, tubes are fun and I learned a bit about coming up with a new OPT as well. And, it was fun. So I'll go pet my hound and crank some tubes--oops!--tunes now. I also have the excellent Bryston 4Bst bipolar transistor amp, and rotate that with the tube ones every so often. Only real difference is the bottomless base of the Bryston, which is only noticeable with music that has that. Of course, the Bryston has near bottomless power compared to the tube ones as well, but I never need all of what just the tube amp can deliver, which is about 80W per side at about 0.15% THD. Plenty for me. "Circlotron" was the brand name given to a tube amp pioneered by I think it was General Electric, which has that topology in the 1950's. The advertisers took the diamond-shaped bridge look of the output stage diagram, rounded it into a circle, and dubbed it 'circlotron'. So, bottom line is, enjoy whatever tickles your nun-handles.

 

[egellings]

LOL, no, but they can set fire to the drapes.

Drapes? What drapes? The amplifier chasses have bottom plates on them and there is nothing on top of the amp that could burn, what with all transformers encased in steel end covers. If a transformer or something in the bottom of the amplifier were to burn, the fire would be completely encased in steel. The tubes have vented covers over them for fire & electrical safety as well, should a tube shatter for some reason. I've done my work to make them safe, and they use a UL/CE approved fused power entry module & cord. The only thing that could set fire to the drapes would be me doing something stupid, not the amps.