When It Comes To Bass, Power Means Nothing
It seems everybody is looking for better bass. Especially if they are replacing a tube amp that has no slam, or bass that has poor definition. So they make the mistake of buying more power. Unfortunately, power means nothing when it comes to sound quality, dynamics, and bass slam. That’s true with solid state, and it’s even MORE so with tube components. A tube amp can have 200 watts per channel, but if it doesn’t have output transformers with enough bandwidth, the speakers won’t receive it. This is the great fact. Not to mention you are only using maybe 10 watts of power when you listen to music, but more on that later.
In the December 2015 issue of Stereophile, magazine editor John Atkinson wrote a review of the YG Acoustics Carmel 2, a speaker that is more power-hungry than most with a sensitivity of 87dB. He could not get the bass response to sound right, even though he tried four different top-rated solid state amps including:
- Arcam FMJ P49 200 watts/channel $4999
- Parasound Halo JC-1 Monoblocks, 400 watts/channel $8990 pair
- Pass XA60.5 Monoblocks, 60 watts/channel $11,000
- MBL Corona C15 Monoblocks, 280 watts/channel $25,000 a pair
None of them were capable of bringing this excellent speaker to its full potential. John Atkinson is clear about one thing: He won't use a tube amp to write a speaker review, because most all of them don't measure well. He repeated that again in this review when he said, "if you've been following my loudspeaker reviews for any length of time, you'll have noted that I almost never use tube amplification."
Luck was on his side. At the same moment he was trying to solve this problem, Robert Deutsch was finishing his review of the PrimaLuna DiaLogue Premium HP integrated, and Atkinson was tasked with measuring its performance as he does for every amplifier reviewed in Stereophile. He was clearly impressed, stating "The flat tops and bottoms of these square waves correlate with the amplifiers extended low bass response; PrimaLuna’s output transformers are of excellent quality." He was also impressed with another one of our trademarks, our low output impedance.
So impressed, Atkinson did something we have never seen before: He used a tube amp to write a speaker review. Not only that, he ran it in triode operation, a mere 36 watts per channel! How surprising is this? Well, think of it this way: Imagine Donald Trump has a press conference surrounded by rainbows and unicorns.
When he finished the review, even he could not hide his amazement when he declared "But once I found the amplifier – a tube integrated! – that also played to its strengths, I very much enjoyed my time with the Carmel 2."
The most important and expensive parts in a tube amplifier are the output transformers. Almost without exception, everybody buys "off the shelf" because of ease and lower cost. And they will try to save money by getting something "good enough". PrimaLuna is one of only a few manufacturers in the world that actually designs and winds our power and output transformers in-house. Our engineering is performed by two top tier designers, one in The Netherlands and one in the United States. No expense is spared. That is why products that cost twice as much will never sound as good as a PrimaLuna.
When you go from ProLogue Classic integrated up to ProLogue Premium, then up to DiaLogue Premium, one of the things you are improving is larger output transformers. The power remains the same as they all run four output tubes. Power, as we stated, means nothing. If you do need unyielding power, go to our incredible HP models which double the number of output tubes.
If you’re not technical, it’s difficult to let go of the idea that for some reason you need 100 watts. That number is so easy to grasp, and tube newbies will cling to it. You are really hurting yourself because if you demand more power from a tube, it will wear out faster or, even worse short because you are running higher voltages. We could easily double the output power of our amps by simply raising voltages. But you would hate us in 9 or 12 months. Read more about that in our section on tube life.
The other way you will hurt yourself is buying an amp you now have to sell later which is a hassle and costs money, like this gentleman:
Here are some facts you need to know:
Never pay attention to speakers' power ratings. Manufacturers simply put them there because they have to. They don’t know if you are buying a solid state or a tube amplifier. Nobody who is well-read will even look at that number. The number you need to look at in the speaker specifications is sensitivity.
A speaker that is 87dB efficient will require twice as much power to achieve the same volume as a speaker that is rated at 90dB. Sensitivity of 87dB is a little low, so that speaker is a smidge power hungry. John Atkinson wrote a review of the YG Acoustics speaker above with 36 watts.
For most people, 36 watts is all you need. Read about our ProLogue Premium integrated which has been used now as a reference by Stereophile reviewer Robert Deutsch for years. He recently commented on it again stating:
“Ever since I reviewed PrimaLuna’s ProLogue Premium, for the June 2012 issue, it has been the model I turn to when I wanted a moderately priced integrated amplifier to try with a new speaker. It never disappointed me, and never seemed outclassed, even when the speaker was the Martin Logan Montis ($10,000/pair). At $2399, the ProLogue Premium to me represents the “sweet spot” for systems in the range of $4,000-$10,000 or higher.”
That's right. He even used it to review Martin Logan electrostatic speakers. Robert Deutsch could call literally any tube amp manufacturer and ask to use an $8,000 integrated, and they wouldn't simply FedEx it, they would hand-deliver it.
But if you want the ultimate in high power, get our HP, or even better yet run two PrimaLuna amplifiers as monoblocks. In monoblock configuration, PrimaLuna amps are one of the very few in the world that will operate with TWO output transformers per channel. Read about that here.
To learn more about power, you can download an SPL meter app onto your phone and check for yourself. If your speaker is rated at 90dB efficiency, that is the amount of volume you get running one watt of power measured one meter from the speaker. Run a white noise or pink noise signal from a test CD and put your phone one meter away from your speaker. Now to go 3dB higher in volume, you will need to double the power. To go another 3dB up, you will need to double the power again. Most people are amazed to see that for most listening you are using under 10 watts of power.
We aren't suggesting this as being a way to quantify your needs. We simply want you to know what affects real sound quality. It's power quality, not power quantity.