PrimaLuna Dialogue Seven Tube Amp Review

[egellings]

I prefer my own home-brewed circlotrons. I even twisted up & stacked the OPTs for them.

 

[fpitas]

As to why current tube amps such as the Prima Luna measure worse than amps from the '60s, I suspect they are designed and tuned that way, i.e. to produce more of what the makers presume tube-lovers like. In fact most current tube amps are caricatures of the '50s amps.

I hope you're right. The alternative is gross incompetence. Either way, they are no longer properly functioning amps from a hi-fi viewpoint; they've become special effects boxes.

 

[amirm]

Might this Prima Luna 7 be malfunctioning?

If not and given the insistence of many ASR members that differences among properly functioning amp are inaudible, how could Amir here a difference from Topping LA90? Or was the LA90 malfunctioning?

No, it is functioning fine.

What I hear at lower frequencies is the response of the speaker changing due to high output impedance of the amp. What I hear at higher volumes is massive amount of distortion as the amp is pushed:

As high as the distortion already is, see the secondary rise starting at 30 watts. And then it clips at 83 watts.

For any listening tests, it is critical to first push the amp to point of breaking so that you can become familiar with what that sounds like. Then you can turn the volume down to see when that effect goes away. Without this, and a reference, it is hard to know something has gone wrong.

 

[Sal1950]

Bookmark this for examples of when amps really do make an audible difference.

And not for the better if you have any interest in High Fidelity..

If not and given the insistence of many ASR members that differences among properly functioning amp are inaudible, how could Amir here a difference from Topping LA90? Or was the LA90 malfunctioning?

By proper amplifier design standards of the last 40+ years or so, this is not a "properly functioning" amp.
It is broken by design.
But I think you already know and understand that.

 

[amirm]

I just noticed that i had forgotten to post the power sweeps at different frequencies. Just added it to the review:

As we see, 1 kHz is the optimal frequency. The situation gets worse at higher frequencies and just falls apart at 20 Hz. This is why there are clearly audible artifacts.

 

[beefkabob]

 

[Murray A]

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!

 

[Descartes]

No wonder there are always so many of these for sale on USAudiomart and Audiogon, the websites of great regret. I just looked up the former and there are 33 Primaluna products for sale! That tells you everything you need to know.

I take it Amir didn't hear the magical three-dimensionality that California tube scam artist says can only be heard with such gear, lol.

I had bought a Prima Luna on sale but barely used it as it always ran so horribly hot!

 

[Sal1950]

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!

Sure, bias sighted listening. The absolute, number one, most unreliable way to judge a components sound quality available to man.

 

[Ken1951]

Sure, bias sighted listening. The absolute, number one, most unreliable way to judge a components sound quality available to man.

Truth! Supremacy in performance is clearly seen in measurements. This amp is certainly in the running for supremacy in failure of performance. And would have been so 45-50 years ago as well.

 

[ahofer]

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!

This particular example says, to me, if you want this sort of sound, it would be much cheaper (and infinitely more flexible) to invest in some EQ and/or digital tube saturation effects.

 

[fpitas]

my advice to newbies is check out any gear by actually hearing it in person, before writing the cheque!

Have to agree with the others: that's bad advice. Especially considering not only the poor measurements here, but Amir's listening impressions.

 

[Bob from Florida]

Have to agree with the others: that's bad advice. Especially considering not only the poor measurements here, but Amir's listening impressions.

Whether you think measuring should provide all or listening first - make sure you can return the product or resell easily before purchasing.

 

[DanielT]

Buy without listening. Cables, DAC and even a good tested amplifier I can easily buy without listening BUT what about speakers? There are different opinions about that here on ASR:

Who would buy a speaker without listening to it?

I have seen this question come up a few times. I think things have changed over the last 20 years in terms of the quality and quantity of information we now have access to. Does that change anyone's view? I would never have considered doing this 20 years ago, a few of my recent purchases...

audiosciencereview.com

Edit:
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.

 

[fpitas]

Just the thought of "listening" to cables makes me shudder.

They have feelings, too!

 

[egellings]

Buy without listening. Cables, DAC and even a good tested amplifier I can easily buy without listening BUT what about speakers? There are different opinions about that here on ASR:

https://audiosciencereview.com/foru...-buy-a-speaker-without-listening-to-it.38126/

I think that with semiconductor-based amplifiers, that would work. With vacuum tube stuff, amp-speaker interactions come into play due to the voltage divider effect between the high-ish output impedance of the tube amp (could be an ohm or more) and the reactive (not purely resistive) impedance of the speaker, which varies a lot from speaker-to-speaker model.

 

[DanielT]

I think that with semiconductor-based amplifiers, that would work. With vacuum tube stuff, amp-speaker interactions come into play due to the voltage divider effect between the high-ish output impedance of the tube amp (could be an ohm or more) and the reactive (not purely resistive) impedance of the speaker, which varies a lot from speaker-to-speaker model.

Exactly and with good amps I don't attribute to that category. And if you really want to color the sound, do this:

This particular example says, to me, if you want this sort of sound, it would be much cheaper (and infinitely more flexible) to invest in some EQ and/or digital tube saturation effects.

And EQ is now free to do as well, so you save a lot of $.

 

[fpitas]

And EQ is now free to do as well, so you save a lot of $

But EQ doesn't glow. And require replacement periodically.

 

[DanielT]

But EQ doesn't glow. And require replacement periodically.

Hypex plus...

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

 

[egellings]

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

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.