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Sunday, September 16, 2012

How Does It Sound? (Part 3)


In part 1 and part 2 of this series of articles I wrote a lot about my thoughts of sound, especially what I am looking for in terms of how a system should sound. In the recent time I often was asked how certain amps or even parts sound and I see an increasing amount of discussion about the sound on forums recently. So I thought it's time for another post about this topic.

While I can understand that people want to gather information about the sound of an amp or any other component before they make a decision, I would like to remind you about the subjectivity in sound judgements and also the system synergy which is involved. There are so many aspects involved in the overall sound result of a system. It is impossible to derive the contribution of a single component and how it would work in another context.

A topic often discussed among DIYers is the sound of the output tube. I already covered that in the last article. Besides the output tube, the next component which is most often discussed is the output transformer. Whenever somebody asks about the 'best' transformer for a certain tube, he will get a whole array of suggestions. Most often all other parameters around the output stage are completely ignored. There is a wide range of suitable load impedances for each tube and yet a wider range of speakers which can be connected. All this should be carefully considered. What might work well with one speaker can sound mediocre with another. Sometimes the seemingly lesser quality transformer can be the better choice in a certain system. Most important is a sensible overall balance. It is quite pointless to pick the transformer which is recommended from most people if the rest of the amp is not up to the task. The transformer which gets the most praise is often quite costly. It would be a big mistake to invest most of the budget in output tube and transformer and then cheap out with the driver stage and power supply. This will yield a worse sounding amp than balancing the budget. Rather get a more affordable output transformer and invest also in a good driver stage and decent power supply. These contribute just as much to the result. As a rough guideline I would recommend to spend about equal amounts of the budget for driver, power supply and output stage. I even have built amps with a driver stage that was more costly than the output stage and the sound result was well worth it.

Whenever you have the chance to listen yourself, do that and trust your own ears, no matter what others say. Many people seem to go for opinions they read in the internet or in magazines rather than choosing what they like best. Keep in mind that everybody has different tastes and preferences. The opinion which you read somewhere might be written by someone who likes a totally different sound than you! For many listeners all that counts is soundstage and a holographic presentation. They often listen only for that and tend to ignore other aspects of the sound. For others soundstage is completely irrelevant and they cosnider it as some artificial effect. Some like extreme resolution and want to be able to hear every bit of detail. Others find that distracting and are looking for ambience and tone.

But how should you get started if you haven't had the chance to listen to many systems yet. May be you live in a remote area where it is diffucult to find other people to have joint listeng sessions. Then the internet seems to be the sensible choice to get advice. This is understandable. Just take some precaution whenever you read about sound evaluations. Try to understand the context in which the system or component was evaluated. Try to get a feel for what the listener is preferring in terms of sound. Does it resemble your own preference? What were the sources used? A sound judgement done with digital front end might be less useful for you if you are a die hard analog junkie. Also keep in mind that people tend to be enthusiastic about anything which they just got or changed. Often the fact that soemthing sounds different leads to the judgement that it's better. Rarely will people correct their first enthusiastic rant about a new amp or new output transformer when they realised that it was not really better after they lived a while with it. If you want to rely one someone else's judgement get a feel about what they like. Also how their systems evovled over the years. Is there a consistent path in the development or a wild jumping around from one extreme to the other.

The more someone rants about how things made a 'day and night' difference in sound, the bigger the grain of salt you should take this with. In a well evolved system, no change will make a huge difference. That would be a sign that the system was not at a very high level before the change.

Although I wrote about power amps mostly above, the same is valid for other areas of the system especially when it comes to preamps there are a whole lot of things coming into play how they fit into the system in terms of output impedance and overall gain. A topic that shall be covered in a future installment of  'How Does It Sound?'. Stay tuned!

Best regards



  1. You are obviously a well seasoned listener and builder offering excellent advice to the less experienced.

    Given your own stated preferences (with which I am in alignment) can you point to some published amp designs you have heard with any of the Klipsh heratage series speakers and that you thought a good pairing? Put an other way, what do you think PWK meant by a good 5 watt amp?

    I have read this whole article and much of what you've published in the last 5 years. I understand the problem of context. If there is anyone who can sort out sucess from poor results It'd be a designer of you caliber.

  2. Hi John,

    I have not much listening experience of the Klipsch Heritage speakers with my amps. I am sure they would work well with any of my 6CB5A designs which I published. These give the best sound for the money within reasonable budget