- Jul 21, 2018
- The Neitherlands
Much like @solderdude stated, this FR discrepancy will only be enhanced by a speaker load, not reduced. The HF difference will likely be a few dB more than what the 4 ohm resistive load is causing. HF hearing loss is different for most people but, let's look at 12 khz as an example; we can see that with a 4 ohm resistive load the peak to peak difference is about 0.8 dB. Assuming we're using a speaker load, this difference will likely be around 1 dB or greater. 12-15 khz is a very sensitive area of our hearing as equal-loudness contours would suggest - if you've tested your own hearing you likely know there is a region above 10 khz which is more sensitive than above or below. Any increase in SPL in this region would cause the amp to sound brighter than an amp with flat FR regardless of hearing ability. In the case of someone who is just starting to experience HF hearing loss, this would more than likely cause the amp to sound closer to neutral as opposed to rolled off.I see!
And that @solderdude and @Blumlein 88 have liked it, interesting.
So here is a question to everyone:
- the worst case scenario (on the worst channel) is a slow rise to 0.6dB at 10kHz to about 1.2dB at 18kHz. Regardless of other failings of this amp, what demographic can even detect such a HF rise? Or benefit from it, to the point of buying it? (that was the point, if I recall)
I still say a demographic with very very good hearing! don't believe me? dial a 1.2dB parametric equaliser setting at 18Khz (Q possibly 0.2), and test it for yourself.
I am not saying it is beyond audibility! we are talking demographic of people with good or poor hearing.
This amp has multiple serious flaws! this minor, zoomed in FR discrepancy is neither here nor there.
It's like having a go at Hitler, because he was short!
confusing!!!! do you mean to say Dynaco is good? or Krell is better or Hypex is best?? (sorry, English is not my strength or I may not high in grey matters)Wasteful product: what is the amount of watts/h it requires to generate such a copious distortion? Like many other myths, it banks on the idea that the past was better than the present, and we deviated from some golden era when we went “solid state”. I own a pair of Dynaco ST-35 (one original, one clone): the enjoyment of Music is superior with my old Krell 300i, and light years ahead with any of the Hypex class D amplifiers. A complex Symphony like Mahler’s Third does benefit from the low noise and low distortion of modern amp design and their higher dynamic range.
Ok, Dynaco was one of the first stepping stone at a time in my life when most of my peers were listening to 45 rpm with a piezo needle and 0.5 W 5 cm diameter speakers. My very first sound system was the one in the picture, Christmas 1972. I began improving its sound with a 6 W mono kit amplifier from a company named GBC, now defunct. The Philips 2203 had a line output I put to use. Five years later I was gifted the Dynaco ST-35/PAS 3x from the living room: it landed in my bedroom driving a pair of AR 4x. Among many other stepping stones in the past half century, the Krell KAV-300i was a memorable upgrade, and the Hypex NC400 based mono blocks a very significant one. Yes, I enjoy very much my main present set-up to the point I do not think I will further try to improve it. I wished to point out that I have experienced tube sound, enjoyed it, and moved on.confusing!!!! do you mean to say Dynaco is good? or Krell is better or Hypex is best?? (sorry, English is not my strength or I may not high in grey matters)
I think he's referring to all American muscle cars from the 60's and early 70's. When I got interested in those in my early teens, I remember my dad telling me that anyone can put a big powerful engine in a car, but my little TR6 will run circles around them on the track.Which cars are those?
there are plenty of cars with big engines that also have straight line performance. That isn't the same thing as not being good cars.
Yea it depends on what sells... Old school muscle cars weren't the fastest around the track. But the corvette was also fast and had a big engine.I think he's referring to all American muscle cars from the 60's and early 70's. When I got interested in those in my early teens, I remember my dad telling me that anyone can put a big powerful engine in a car, but my little TR6 will run circles around them on the track.
why you didn't make listening test?
The other reason to measure equipment has nothing to do with how it sounds playing music, but is a measure of the HONESTY of the manufacturer. If the manufacturer says an amplifier can put out 150 watts into 8 ohms with distortion products down 80 dB ( that is THD below 0.01% ) and we measure that amplifier and it hits 1% distortion at 75 watts and gets worse from there on up - well, now we have found that the manufacturer is not being truthful with us. Should we reward manufacturers who lie to the public by spending our hard-earned dollars on their products? I would say, no we should not.
Caveat emptor. Amplifier manufacturers have been lying as long as I remember. At one point some listed a "Peak Power" that could only be (briefly) achieved if you shorted the power supply. They aren't alone; car sub specs are usually complete fabrications, too.In general, I agree with you, specs should be honest, indeed conservative. However, it seems to me that the reality of today's mainly on-line sales is that stuff has got cheaper and cheaper (except the 'High End') and specs have become worthy of the Booker Prize for Fiction. Whoever offers the most power for the least money gets the sale.
Consequently, my approach is to buy on a combination of discounted specs and price, then make my own measurements. If the numbers I get are adequate for the job I need doing, then the item stays, if not, it goes back. I've sent back a few ADC/DAC combinations that distorted heavily above -6dBFS, I've kept some cheap amplifiers that claimed silly amounts of power, but gave a perfectly clean 20 watts into 8 ohms, which is all I needed, for very little money.
I accept that not everyone buying amps etc on-line has the ability to make their own measurements, or even understand what the specs mean, but as long as sales are done at the lowest price, on-line, with no independent advice but with cheap and easy returns, I can't see the situation changing, as much as I would like it to.