NOSValves Posted November 5, 2003 Share Posted November 5, 2003 I was checking a HF81 on the scope this afternoon and thought it would be fun to snap some shots for all to see these are Square Waves. Maybe Mark Deneen will chime in and explain what this all means he can do a much better job then I can explaining it. What's on the scope isn't the end all but its fun all the same. 20 Hz 50 Hz 100Hz 200Hz 800Hz 1.5Khz 5Khz 10Khz 15Khz 20Khz Quote Link to comment Share on other sites More sharing options...
ben. Posted November 5, 2003 Share Posted November 5, 2003 Looks like if I get one, I'd be dissapointed with my large collection of square wave music. Just kidding, I do realize what a square wave will reveal through a scope. At what power level were these taken? How about input level? Interesting results. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 I didn't measure the input level but it isn't large. The output level of the amp at these points is right about 3 to 4 watts. Craig The scope was on 5 Div and 3 lines on the scope ! 15/2 = 7.5 7.5 X .707 = 5.3025 5.3025 X 5.3025 + 28.116506 / 8Ohms = 3.5145632 Watts Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 5, 2003 Share Posted November 5, 2003 The factory has square wave results for ALL the EICOS. They are VERY good, from the HF-35 on down. IF you look at the manual, they are one of the companies that POST square wave comments and results for their amps as they are very good. Better yet, what was your motive to suddenly post all these square waves? IT's pretty known that EICOs do well on the bench. IS this one before or after you worked on it? Quote Link to comment Share on other sites More sharing options...
Guy Landau Posted November 5, 2003 Share Posted November 5, 2003 Can you take some photos of a clipping Dynakit as well? It probably won't look much different. Quote Link to comment Share on other sites More sharing options...
ben. Posted November 5, 2003 Share Posted November 5, 2003 Cool, thanks. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 Ryan, This amp is flat with a sine wave to about 12 watts but a sine wave tells you very little. I noticed a small variation in the lower and upper registers doing a full power test which wasn't a big deal. A square wave tells a much better story in my opinion. Craig Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 I was going to start doing this with all the amps now and then just for kicks ! It wasn't my Idea Mark did it a long time ago and met with resistance from much the same crowd. Craig Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 I'm going to go redo the first few tests I may have readjusted the output at these points now that I look at it they don't look right. Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 5, 2003 Share Posted November 5, 2003 All I know is EICO seems pretty proud of their square wave results for ALL their amps. Many others dont even post this kind of report. kh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 Kelly Chill out this is all in fun !!! Ryan, I corrected the lower 20Hz 50Hz and added 100Hz Yes I just did a quicky so your right on the figures. I myself could careless if its tested at 1 watt many here may believe the 1 watt garbage but I do not. I use way more than one watt with my amps and I suspect most here do also they just do not realize it. Craig Quote Link to comment Share on other sites More sharing options...
Painful Reality Posted November 5, 2003 Share Posted November 5, 2003 You should put the two traces on the scope i.e. the signal from the tone generator and the signal from the amp. Square waves are quite useful to point out ringing and overshooting. Amps exhibiting these will often sound "hard". Quote Link to comment Share on other sites More sharing options...
jazman Posted November 5, 2003 Share Posted November 5, 2003 NOSValves, I think I smell a rat here. Could your post have anything to do with a comment from another post? "This amplifier has made me a believer in EICO, I also agree that it bests a 299 or 299B." Why am I not surprised to see this type of post from you? Klipsch out. Quote Link to comment Share on other sites More sharing options...
AnalOg Posted November 5, 2003 Share Posted November 5, 2003 You guys crack me up, you're all so predictable! Tom Quote Link to comment Share on other sites More sharing options...
Painful Reality Posted November 5, 2003 Share Posted November 5, 2003 Ryan, Your RMS calculation are for a sine wave. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 5, 2003 Author Share Posted November 5, 2003 Jazzman would you please quit smelling yourself !! Man you are weird Quote Link to comment Share on other sites More sharing options...
jazman Posted November 5, 2003 Share Posted November 5, 2003 NOSV, You're the one smelling up the place. Why did this post appear after someone commented that the Eico bested your two most hawked restoration cash cows? You've achieved a goal often sought after by many here in this forum from their systems. TRANSPARENCY! Klipsch out. Quote Link to comment Share on other sites More sharing options...
Deang Posted November 5, 2003 Share Posted November 5, 2003 Of course what does it matter, for as everyone here has been told a multitude of times -- no two HF-81s sound alike. You either get one that sounds like a dream, or one that sounds so mediocre you mind as well drop kick it from the porch to the curb. Those look pretty rough, I would imagine this one you haven't worked on yet. The pics are pretty cool. What aspect of an amp's circuit determines the square wave response results? Quote Link to comment Share on other sites More sharing options...
michael hurd Posted November 5, 2003 Share Posted November 5, 2003 Wow! I wonder what the output of an average solid state amp would look like, at those frequencies at the same drive levels. Quote Link to comment Share on other sites More sharing options...
Parrot Posted November 5, 2003 Share Posted November 5, 2003 ---------------- On 11/5/2003 6:48:18 PM mobile homeless wrote: The factory has square wave results for ALL the EICOS. They are VERY good, from the HF-35 on down. IF you look at the manual, they are one of the companies that POST square wave comments and results for their amps as they are very good. Better yet, what was your motive to suddenly post all these square waves? ---------------- The factory doesn't have anything. They are no longer in business. Anyway, you're in the camp of "specs are meaningless." Plus, according to you, every single EICO amp sounds different. So what difference does it make if EICO found a 4 usec risetime when they tested a particular amp. That might not apply to the next one made, right? Quote Link to comment Share on other sites More sharing options...
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