PrimaLuna Dialogue Seven Tube Amp Review

[DavidMcRoy]

I you like a certain kind of “tube sound,” get a clean, quiet and stable Class D power amplifier, feed it with your tube buffer of choice and make it easily bypassed. That’s what I do. I view tubes as “audio processors” and they “can be” very enjoyable.

 

[MacClintock]

Thanks for the test Amir. It helped me remember that I'm going to buy a new bread box today.
View attachment 309806
Edit:
Other than that, I really don't know how to comment on this amplifier. Against other tube amps with the same power? If so how does it compare to other tube amps in terms of performance?

Or should you compare tube amps with solid state? If you disregard looks and only concentrate on performance (and why not also price) then tube amps generally don't have a chance, do they?

However, a historical HiFi related question is when did solid state, transistor based amplifiers overtake tube amps in performance? Sometime in the 1960s?

Haha, very funny, I bought almost exactly this bread box a few weeks ago. It costed me $15, looks nice and sounds better than this amp....

 

[Chrispy]

totally agree..unless this has a batch of fresh tubes... then its an invalid test.

Peter

Not invalid but just what it is. How much break-in do those new tubes need, too ? LOL.

 

[kchap]

CLEARLY, @amirm should've tried exotic NOS tubes that cost $1,500 each right?

NOS? Clearly there is a serious shortage of TLAs and someone should do something about it.

 

[D700]

…but but but it’s so pretty! And it makes toast!

 

[GWolfman]

No Panther?

Even headless was too much!

 

[Billy Budapest]

Thoriated tungsten OK.

Isn’t that radioactive?

 

[JSmith]

Oh dear, oh dear,
Our revered Amir..
You have made new enemies
With PrimaLuna dealer everywhere

If your going to dis by poem, at least make it rhyme or use an accepted poem structure... 0 out of 5 stars.


JSmith

 

[MrOtto]

Tube amplifiers are about the idea of how it works, that amplification can be done by a rudimentary and visual method, also the idea of how a mechanical watches work and an aircooled Porsche 911. They are both inferior to quartz watches in accuracy and water cooled engines in term of efficiency.

 

[DanielT]

Human ears are just not very sensitive to distortion. We are much more sensitive to frequency response.

For my own part, I do not have ultra-low distortion speakers, so an amplifier with 60 dB SINAD (as this PrimaLuna Dialogue Seven has) is not something I worry about as long as the amplifier has enough power. I sometimes plug in my vintage receiver HK330C, which has a SINAD around 60 dB. It has never bothered me, as long as I have speakers with decent sensitivity because its power is relatively low.

Worse then with deviant FR that you are in on.
Isn't it said that in descending order of importance for the sound is:
1. FR
2. How the speakers spread the sound.
3. Distortion
That if you exclude the acoustics in the listening room.

 

[Bow_Wazoo]

These measurements remind me of all the dark times in my hifi history. I also had the dialogue one once, and was very proud of it. So the wonderful Focal Electra BE, that I connected to this amp, didn't had it easy... Poor speakers...

 

[Toku]

If you measure a vacuum tube amplifier electrically, you can't help but get such a result. Clearly inferior to the latest semiconductor products.
Tube fans may find the results of amirm unacceptable, but they should accept it as reality and find joy in other aspects.
There are many different ways to enjoy audio. I think that vacuum tube amplifiers are products that should be enjoyed more in other aspects than in their electrical characteristics.
Having grown up surrounded by vacuum tubes since I was a boy, I never use a vacuum tube amp anymore, but I love the glow and nostalgic look of a vacuum tube heater.
This is the only point that semiconductor products cannot imitate.
But the total price tag of $8000 for the set is a bit ridiculous.

 

[DanielT]

But the total price tag of $8000 for the set is a bit ridiculous.

Bread basket with tubes in it with that price tag, performance and that level of power isn't even a bit ridiculous, it's downright ridiculous.

Edit:
For $8000 you can easily get a pair of really good active speakers PLUS if you like HiFi stuff as a contrast a good, stylish, old vintage solid state receiver/amp and speakers for a secondary system. ....plus subwoofer...plus... and so on.

 

[audiotron]

I feel bad for the member that owns it.

 

[milosz]

Isn’t that radioactive?

Yes, a little. Bring your geiger counter near an 811 tube (BIG thoriated cathode) and you'll get a few clicks above background. I've done this. It's true.

 

[milosz]

According to Amir's analysis, this amplifier is the first to show reosnance issues . It also suffers from distortino, which is appropriate since it has an Italian name.

 

[mmuetst]

Art Dudley's was not the only one with a defect in his ears:
See a review of the Boyuurange Reisong A12 here
This one is very positive:

But if you look at the following video (especially the measurement at 14 minutes 15 seconds) you will think differently:

This is one big distortion machine....

I think that a tube amp design can at least be better than what Prima Luna gets out of it

 

[Multicore]

let's admit that these :

Look Koooooler , than

No, I won't. Dunno who that grinning grandpa is but the way he's fondling that hardware is not what I call cool.

 

[Haskil]

And such a Dynaco ST-70 I can definitely see someone who knows electronics tinkering with.
Something that Amir also noted when he tested it:

I love the simplicity of tube amps like this. There is just so little to them. If I were less busy, I wouldn't mind playing with one to get it to optimal performance.

Review and Measurements of Dynaco ST 70

This is a review and detailed measurements of the vintage Dynakit Dynaco Stereo 70. It is on kind loan from a member who bought it used online and repaired it. Previous owner hand upgraded it but could not get it working. Given that it is 60 years old, one can forgive the rust and dust...

audiosciencereview.com

With SINAD around 60 dB for a Dynaco ST-70 vs a solid state with SINAD around 90 dB, how can you hear the difference with a pair of speakers that have, for example, 40 dB distortion? The amp's distortion is then drowned out, or masked by the speakers' distortion, right? Maybe if we are more sensitive to higher order amp distortion than speaker distortion and can thus hear a difference between the amplifier and speaker mentioned in my example?
Given that both amplifiers have straight FR (or small but inaudible FR deviations), so you can discount that factor, that is.

The distortion is not drowned in that of the speakers, it is added to that of the speakers... which is always there because it is intrinsic to them.

When comparing two amplifiers, one of which has high distortion in the mid-high range, it is not at all impossible to hear it compared to the amplifier "without" without distortion...
(An analogy: if you use a scale that is unusable to weigh weights less than 2 kilograms, they will nevertheless indicate weights of 101.5 kilograms...)

In the same way, the linearity defect of an amplifier can be heard even if it is of the order of 0.2 dB... whereas the speaker has an in situ response curve which varies from + or - 5 or 6 dB... but only in comparison with an amp which would not have this defect... Because in abstracto it will not be heard.

A friend has a pair of Revel Salon powered by two 1500 watt Pascal mono blocks reputed to have a treble response varying with the speaker load... Perhaps compared to a Purifi we would hear something at the top of the spectrum, but listened to alone they deliver, connected to these Revels, a listening experience of breathtaking beauty...

 

[jkasch]

Art Dudley, RIP, was a great writer and for all I know, a good person. There was, however, an inverse relationship between measurements and his recommendations. In most cases, the worse something measured the more Art liked it. (I used to subscribe to Stereophile.)