Home » Audio » Thermionic Emissions » tubes vs designs
tubes vs designs [message #8594] Sat, 04 December 2004 11:13 Go to next message
jim denton is currently offline  jim denton
Messages: 162
Registered: May 2009
Master
Now you have me asking more darn questions--Designs??? How is a poor ole Okie guy suppposed to know which desgined amp will provide a wide sound range? (ie--25Hz to 20kHz) ----Is this good thinking? If I build a speaker that can go below 50Hz but the amp won't then I can never hear the abilities of that cabinet--correct? Just like the speaker rolls off at 80Hz and is gone but the amp can go down to 50Hz?--and just for my own FYI---why have 2 of the 6eu7's instead of one (The Magnavox has one and the Wollensak has 2) Jim PS what I have been doing is buying old vingate amps/rec/intergrated's?/and DIY's just to hear the differences---

Re: tubes vs designs [message #8595 is a reply to message #8594] Sat, 04 December 2004 13:32 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18669
Registered: January 2001
Illuminati (33rd Degree)
Just an interjection - I think you'll have more trouble getting wide range from your speakers than from your amps. It has nothing to do with your question about amps, but it does go to the point. If you're worried about 25Hz from tube amps, I'd probably be more focused on the speakers than the amp. Most high efficiency designs are 40Hz and up, and many are more like 60Hz or 80Hz up.

Yes, exactly. [message #8598 is a reply to message #8595] Sat, 04 December 2004 19:50 Go to previous messageGo to next message
Poindexter is currently offline  Poindexter
Messages: 108
Registered: May 2009
Viscount
I don't even worry too much about the low extension of my amps, since I use speaks oriented more toward the whole range than thunderous bass. To me, a speaker that is -3dB at 50Hz is acceptable, and without even trying, I'm getting -1dB at ~20Hz from the amp.

Amps definitely have different 'sounds', and there's no way for me to tell you what you want to hear, you just have to audition, listen,, and decide; but Wayne has it right, the speaks are almost always the low and high freek limitation.

Forum posts and answers from azzles like me are not the answer. You got to try stuff, listen, try again, and post back to us. It's called 'experimentation', and that's what's the answer.

Thanx, Wayne,

Poinz

Re: Yes, exactly. [message #8600 is a reply to message #8598] Sat, 04 December 2004 22:30 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18669
Registered: January 2001
Illuminati (33rd Degree)
No way you're an azzle, more an eggspurt near as I can tell.

Re: tubes vs designs [message #8606 is a reply to message #8594] Tue, 07 December 2004 18:46 Go to previous messageGo to next message
Bill Bittle is currently offline  Bill Bittle
Messages: 2
Registered: May 2009
Esquire
Your ultimate goal should be to get as wide a frequency range out of each component as you can. You want to reduce as many limiting factors as you can. Let's take distortion as an example. A person might wonder why a designer would create a preamp with a .01% distortion figure when the power amp has a figure of .2%. But, if everything, from the source device to the speaker has a little distortion, when you add them all together, the sonic quality of the final end product is diminished. Now, if you can fix even one source of distortion, it will improve the over all sound quality. The same is true for frequency responce, sound stage etc. I can take a poor quality bookshelf speaker with a frequency responce that is 100hz to 12Khz with peaks and valleys in it's frequency response curve and believe me, you can tell the difference between it's sound when driven by some cheap modern IC laden receiver and something like a Fisher 800C. Obviously the 800C would sound better through a better speaker, but even with the described elcheapo speaker, the 800C will still be an improvement over the budget priced modern receiver with it's IC opamp power amps.
As for designs. big factors in tube amps are the quality of the parts. You can have a real fine electronic design but hamstring it with a cheap output transformer. Then there are designs that not only use sub par parts, but are also designed with maximum corporate profit and a devil may care attitude toward sonic quality. In the "Gloden Age" of hi-fi, there were some pretty wild power, frequency bandwidth and distortion figures bantered about by manufacturers. Some were true, many were not. I can assure you that a $59 Arkay stereo amp will not perform like a Scott 299C no matter how high they rate the amp.
Also, test data only tells a part of the story. An amp may look good on the spec sheet, but sound worse then an amp that may have shown higher distortion figures and a lower high frequency roll off.
Then there is power. For a real good example of how this figure can be manipulated take a listen to a 70's vintage Marantz 2200 series 'Blue Face" receiver and then compare it to any modern amplifier rated at the same power. Believe me, I do not have to elaborate any more.
So there are a lot of variables and such in audio. Design, tube vs Transistor vs IC, as well as the ever confusing array of amplifier specs. The bottom line is this. Do you like the way it sounds? if so then it is the setup for you. If not,then you will probably join the ranks of millions of audiophiles who are on the never ending quest for sonic nirvana.


Re: tubes vs designs [message #8840 is a reply to message #8606] Fri, 25 February 2005 23:58 Go to previous message
Steve is currently offline  Steve
Messages: 83
Registered: May 2009
Viscount
Hi Guys,

Nice points Bill. If I may expand on Bill's comment about minimizing distortion.

That point is that the distortion products multiply, a second harmonic combines with a second harmonic in the following stage, producing 4th harmonics. If we can minimize one of the second harmonics, then the resultant 4th will also be minimized.

This scenario really gets ugly with multiple stages as we start dealing with higher orders.

Hope this helps.
Steve

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