Max2 Posted November 25, 2014 Share Posted November 25, 2014 Check out the THD. Great numbers down very low in the 1-3 watt range (.005% ish), 5 watts it drops roughly .002% and drops even further in the .001% range once it hits 25 watts. How about 100 watts at .0015% anyone? Doesn't matter to me in the least. I listen to music, not test tones. If you can tell the difference between 0.5% and 0.0015% distortion, you are a bat and probably can't afford a high end stereo system..... Im surprised someone that is a RCA cable roller and a speaker wire enthusiast would scoff at hard data. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 25, 2014 Share Posted November 25, 2014 Im surprised someone that is a RCA cable roller and a speaker wire enthusiast would scoff at hard data. I'm not. 1 Quote Link to comment Share on other sites More sharing options...
JL Sargent Posted November 25, 2014 Share Posted November 25, 2014 (edited) I once had a Clarion car stereo with 10% THD at 10 watts per. I really could hear that level of noise! It was an unwelcomed affect. Edited November 25, 2014 by JL Sargent Quote Link to comment Share on other sites More sharing options...
Shakeydeal Posted November 25, 2014 Share Posted November 25, 2014 Check out the THD. Great numbers down very low in the 1-3 watt range (.005% ish), 5 watts it drops roughly .002% and drops even further in the .001% range once it hits 25 watts. How about 100 watts at .0015% anyone? Doesn't matter to me in the least. I listen to music, not test tones. If you can tell the difference between 0.5% and 0.0015% distortion, you are a bat and probably can't afford a high end stereo system..... Im surprised someone that is a RCA cable roller and a speaker wire enthusiast would scoff at hard data. My amp probably has ~1% distortion at rated output and I would bet dollars to doughnuts that it sounds better than any Emotiva or Outlaw amp. And that, my friend, is something you don't need an oscilloscope to hear......... Shakey 1 Quote Link to comment Share on other sites More sharing options...
mark1101 Posted November 25, 2014 Share Posted November 25, 2014 Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 25, 2014 Share Posted November 25, 2014 My amp probably has ~1% distortion at rated output and I would bet dollars to doughnuts that it sounds better than any Emotiva or Outlaw amp Chocolate old fashioned for me Quote Link to comment Share on other sites More sharing options...
mark1101 Posted November 25, 2014 Share Posted November 25, 2014 (edited) You guys........... You are completely missing the boat here with regard to the "no gain controls". It matters ZERO how low the distortion is on your amp. If it has no gain controls then it is ON FULL BLAST all the time. When you want to listen to music at a low level and you turn your preamp way down..........you are hitting your amp with a very low signal from the preamp. I'm sure you have heard of signal to noise ratio. When the signal is very low then you are sending a low signal to noise ratio into the amp. The amp can be CLEAN CLEAN CLEAN...............but unfortunately it makes no difference because the signal being fed already has the noise IN IT. The amp will be noisy because it is amplifying a noisy signal. You want to use A LOT of your preamp.........and only A LITTLE of your amp.........only what you need to get it to the loudest you will ever listen. That will more than likely be less than half way on teh knob. WHen you do this...........you will not here the HISS because the singal to noise ratio is HIGH. The fellow above with the EMO equipment and his DIY attentuators..............he figured it out. Edit: So in summation..............it is far better to spend your money on a very good preamp. You can get away with mediocre amps if you do that. Most of the noise comes from up front...........before the amps. Most amps, even inexpensive ones are far cleaner than you really need them to be. IT'S THE PREAMP that matters most. As an example I am using rebuilt Mac amps from the 70s with very high distortion figures compared to day's amp's specs. They sound absolutley terrific with Klipsch speakers. I get fantastic sound mainly because I put all the money in the preamp...........of course the most money went into the speakers. Edited November 25, 2014 by mark1101 Quote Link to comment Share on other sites More sharing options...
Shakeydeal Posted November 25, 2014 Share Posted November 25, 2014 The best way to accomplish this is by using an amp with a high input sensitivity paired with a passive linestage. Active preamps (unless used with very insensitive high powered SS amps) throw away all the gain that is accomplished by the amp. It is a very inefficient way to accomplish things. Shakey Quote Link to comment Share on other sites More sharing options...
TasDom Posted November 25, 2014 Share Posted November 25, 2014 (edited) The fellow above with the EMO equipment and his DIY attentuators..............he figured it out. So did the guy using the Mini-X (volume at about 9:00) with his Belle's and not using his XPA-5s Edited November 25, 2014 by Tasdom Quote Link to comment Share on other sites More sharing options...
babadono Posted November 25, 2014 Share Posted November 25, 2014 Problem is NOBODY needs 200 watts per with klipsch speakers!!! You're painting with a broad brush there Jeff. Headroom is never a bad thing. Transient spikes will eat up amp power in a heartbeat. Distance from the speakers needs to be factored in as well. I'd rather have too much than not enough. That was for affect, did it work? Yes, I always pick the low hanging fruit. My RF7-IIs suck down lotsa watts. And I believe at some freqs their impedance dips below 4 ohms, i.e. they need current. Quote Link to comment Share on other sites More sharing options...
babadono Posted November 25, 2014 Share Posted November 25, 2014 Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. So you are not changing the "gain" of the power amp, just attenuating the input signal. Which of course allows you to run your preamp harder (out of the noise). Quote Link to comment Share on other sites More sharing options...
Max2 Posted November 25, 2014 Share Posted November 25, 2014 (edited) Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. So you are not changing the "gain" of the power amp, just attenuating the input signal. Which of course allows you to run your preamp harder (out of the noise). Right. Most pre's spec well beyond any decent amp anyway. Why limit the output of your amp by cutting its signal unless you are covering up dirty amp outputs or a dirty para EQ from an active setup, etc, etc. Edited November 25, 2014 by Max2 Quote Link to comment Share on other sites More sharing options...
mark1101 Posted November 25, 2014 Share Posted November 25, 2014 Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. So you are not changing the "gain" of the power amp, just attenuating the input signal. Which of course allows you to run your preamp harder (out of the noise). Right. Most pre's spec well beyond any decent amp anyway. Why limit the output of your amp by cutting its signal unless you are covering up dirty amp outputs or a dirty para EQ from an active setup, etc, etc. By having the attenuators after the preamp you are NOT reducing the signal to noise ratio just the voltage of the signal going into the amp. Quote Link to comment Share on other sites More sharing options...
Max2 Posted November 25, 2014 Share Posted November 25, 2014 Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. So you are not changing the "gain" of the power amp, just attenuating the input signal. Which of course allows you to run your preamp harder (out of the noise). Right. Most pre's spec well beyond any decent amp anyway. Why limit the output of your amp by cutting its signal unless you are covering up dirty amp outputs or a dirty para EQ from an active setup, etc, etc. By having the attenuators after the preamp you are NOT reducing the signal to noise ratio just the voltage of the signal going into the amp. Yes, but you are still just relying on how "clean" the signal is being cut by resistive pots and what not. Why go to all this trouble when you can buy a remarkable, affordable, QUIET, extremely low THD amp from the get go at darn near a giveaway price? Unless of course you're a tube fan. Quote Link to comment Share on other sites More sharing options...
Arkytype Posted November 26, 2014 Share Posted November 26, 2014 So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea Thanks! Most all the Emotiva gear can be rack mounted and as long as you provide adequate space between them, you should have a long-lived system. All the pots are 25k ohm audio taper. The three pots currently in use are connected between the USP-1's FULL RANGE L & R outputs (Klipschorns) and from the HIGH PASS L & R outputs wyed together for the center channel Belle. Everything is housed in a Raxxess ROTR Pull-Out and Rotating Rack and fed with an RF-filtered 1.5 kW balanced power transformer with a dedicated ground. This has meant a trouble-free no hum install. Lee Quote Link to comment Share on other sites More sharing options...
mark1101 Posted November 26, 2014 Share Posted November 26, 2014 Custom panel.jpgCan't the gain of an Emotiva amp be turned down with a little hot rodding? In short, the answer is yes. I purchased an all-Emo setup about a year ago and have been very pleased with it. The UPA-500 was purchased with the idea of eventually running my Klipschorns 2-way with an active crossover which does not have a global volume control. The 5th channel would power my passive 3-way center channel Belle. I had RCI Custom Products engrave and punch the panel. The knobs are from Kilo International. Behind the rack panel is an attached chassis with RCA connectors on the rear panel. Since I do a lot of acoustical testing, I added two auxiliary inputs on the front panel. Lee So these are in line volume controls between the preamp outputs and the amp inputs? You used the rack itself for the install. Wow, nice job. Good idea. So you are not changing the "gain" of the power amp, just attenuating the input signal. Which of course allows you to run your preamp harder (out of the noise). Right. Most pre's spec well beyond any decent amp anyway. Why limit the output of your amp by cutting its signal unless you are covering up dirty amp outputs or a dirty para EQ from an active setup, etc, etc. By having the attenuators after the preamp you are NOT reducing the signal to noise ratio just the voltage of the signal going into the amp. Yes, but you are still just relying on how "clean" the signal is being cut by resistive pots and what not. Why go to all this trouble when you can buy a remarkable, affordable, QUIET, extremely low THD amp from the get go at darn near a giveaway price? Unless of course you're a tube fan. You still don't get it. Do whatever you want...... Quote Link to comment Share on other sites More sharing options...
Max2 Posted November 26, 2014 Share Posted November 26, 2014 You still don't get it. Do whatever you want...... Now wait, Im trying here It looks to me like you're just adding another "volume knob" downstream of the pre for the signal. I totally get killing an idle hiss with this, but how have you improved or cleaned the sound the amp is producing at 1watt or full power? Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 26, 2014 Share Posted November 26, 2014 Now wait, Im trying here It looks to me like you're just adding another "volume knob" downstream of the pre for the signal. I totally get killing an idle hiss with this, but how have you improved or cleaned the sound the amp is producing at 1watt or full power? I'm sure you have heard of signal to noise ratio. When the signal is very low then you are sending a low signal to noise ratio into the amp. The amp can be CLEAN CLEAN CLEAN...............but unfortunately it makes no difference because the signal being fed already has the noise IN IT. The amp will be noisy because it is amplifying a noisy signal. You want to use A LOT of your preamp.........and only A LITTLE of your amp.........only what you need to get it to the loudest you will ever listen. That will more than likely be less than half way on teh knob. WHen you do this...........you will not here the HISS because the singal to noise ratio is HIGH. Quote Link to comment Share on other sites More sharing options...
Ski Bum Posted November 26, 2014 Share Posted November 26, 2014 (edited) Now wait, Im trying here It looks to me like you're just adding another "volume knob" downstream of the pre for the signal. I totally get killing an idle hiss with this, but how have you improved or cleaned the sound the amp is producing at 1watt or full power? I'm sure you have heard of signal to noise ratio. When the signal is very low then you are sending a low signal to noise ratio into the amp. The amp can be CLEAN CLEAN CLEAN...............but unfortunately it makes no difference because the signal being fed already has the noise IN IT. The amp will be noisy because it is amplifying a noisy signal. You want to use A LOT of your preamp.........and only A LITTLE of your amp.........only what you need to get it to the loudest you will ever listen. That will more than likely be less than half way on teh knob. WHen you do this...........you will not here the HISS because the singal to noise ratio is HIGH. Real world example...my amp's input sensitivity is 1.2v for full power. Now, the portion of the input that accounts for the noise is a fraction of a volt and constant, let's call it x; the music signal is anything above that up to 1.2v, for a best case s/n of 1.2/x. Now I adjust the "gain" control or input sensitivity control on my amp so it requires 2v for full output. Note that 2/x > 1.2/x. The amps only give what they get, so give them the higher s/n signal. IIRC, those Emo amps only require ~0.7v for full power, which means less wiggle room, the noise is inevitably closer to being audible. Edited November 26, 2014 by Ski Bum Quote Link to comment Share on other sites More sharing options...
Shakeydeal Posted November 26, 2014 Share Posted November 26, 2014 I have to say I would rather have the voltage gain happen at the amplifier and not at the preamp at all. Less attenuation (and circuitry in the signal path) is always a good thing. I have owned active linestages up to 8K and none of them sounded as good as an autoformer or transformer based passive. And with high sensitivity speakers like all you guys have, you should hardly ever need an active preamp. Get the input sensitivity of the amp and the output impedance and voltage output of the source right, and you are golden with a "good" passive device. However if you have low sensitivity speakers and a very hard to drive high power SS amp, this won't work. Most people here don't fall into that camp. Shakey Quote Link to comment Share on other sites More sharing options...
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