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post #1 of 109 Old 04-13-2014, 08:52 PM - Thread Starter
 
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Hi All:

 

I'm an old dog with experience in amplifier design, debugging and goodness testing. I also have a decent background in audio transducer development and speaker system design.

 

These days, I have a closet full of test equipment and I wouldn't mind pulling it out and have some leisure fun, with it.

 

By old dog, I didn't mean to imply that I am retired, but that I have participated in all things audio since the 1970's. I am currently employed as an engineer within one of the many audio fields of discipline.

 

I'm looking to have some fun by taking request for product testing, or design assistance. I don't have the time to engage in extremely deep sharing's or debates, but most certainly meaningful and useful sharing's etc.

 

All of my gear is lab grade, as such; the potential exist for solid measurements, containing trust worthy depictions of performance(s).

 

Please feel free to reach out and say hello and spark up conversation. I'm open to any vertical of audio debate and sharing: Consumer Audio; Pro-Audio; Commercial Audio and everything in between.

 

Best regards and an open invitation to all,

 

GF

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post #2 of 109 Old 04-13-2014, 09:37 PM - Thread Starter
 
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I guess no takers....

 

hmmm

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post #3 of 109 Old 04-16-2014, 04:07 PM
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I have a question actually. Since I've never used pro power amp for home use and vice versa, is there any advantage (or disadvantage) of using pro/commercial-grade amp such as Behringer, Alesis, Crown for home listening (especially two-channel audio) -- I currently use a Moon 330U power amp, System Audio Aura 30 speakers. XLO speaker wire (can't remember which model, but it's the one with 8 AWG.

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post #4 of 109 Old 04-16-2014, 04:24 PM
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post #5 of 109 Old 04-16-2014, 08:31 PM - Thread Starter
 
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Quote:
Originally Posted by David Susilo View Post

I have a question actually. Since I've never used pro power amp for home use and vice versa, is there any advantage (or disadvantage) of using pro/commercial-grade amp such as Behringer, Alesis, Crown for home listening (especially two-channel audio) -- I currently use a Moon 330U power amp, System Audio Aura 30 speakers. XLO speaker wire (can't remember which model, but it's the one with 8 AWG.

Hi David:

 

Thanks for your question. I will attempt to answer it; and I suspect that it will take more than one exhange to fully answer questions, if at all possible.However, this will also be my last post in AVS...

 

The power that be, keep deleting my posts and my threads, and have locked me out of from what I can tell, is any thread that has Arnold in. I guess they're trying to keep him from being embarrassed...

 

I would be honestly shocked if this post isn't also censored... I would be impressed if it isn't...I'll check back in a few days to see...

 

It was just starting to get interesting... Bummer! Egos & Icons and all that... I'm glad I'm not afflicted, with either.

 

 

Anyway - Moving on to my more direct answers...

 

Big question! The answers is, it depends.

 

Each of those brands that you mentioned, make reference audio products, pro-audio products and Crown also makes commercial grade products, and I know the Behringer is also entering this space as well, they might already be there...

 

As a general rule, commercial amps tend to be a bit noisy and often have somewhat limited bandwidths (for a couple of intentional reasons); however, that doesn't disqualify them, if the noise can be adequacy massed and the bandwidth fits the application. If you already own one such product, try it out.

 

Proaudio gear has a range of quality, and pricing... again, there is no reason why you could not consider using this category of product either. In fact, it is this category of amplification that is used in most move and stage acting theaters around the world, so your living, could also be a fit... Pricing and feature set is becoming a real tempter in this space. Peavey has a new line of D- Class amps, with on-board DSP, that weigh in at couple of Ibs starting at $300.00 - 2x 200 Watts - I'd have listen to that product for sure.. you can save a hundred bucks on drop the DSP...

 

Reference amps from any and all manufacturers seem to be the products of mainstream choice, for home theater buffs that decide to go the full pre-pro-amp path, if you will. Reference typically implies, that the series of product from a given manufacturer is near or at the top of their SQ options. You mentioned two brands, Alesis and Alesis, I mean Behringer... I've tested the A500 on a bench after several hour of ABX listing at my home and did discover a positive correlation between the two method evaluation. The A500 has a problem around 1Khz. A very audible and visual distortion, if you will; is present in them. I say them because I had two and both had the same short-coming. Outside of this, it seemed to be a great amp, = nice tone, adequate headroom, nice upgrade above most integrated offerings; and within the context of a home theatre application, could very well be a sensible fit. at $200.00, there's a lot left to like.I have not listened to or tested the Alesis. For critical listening in a 2-channel set up, the flaw forces me to have you look onward...

 

Over the years and recently as well, I have listened to and put a measuring device to many, if not most of the main stream models in commercial and pro-audio verticals; mainly because they're easy to come across and are often being more precisely calibrated and match to their respectively assigned pre-amp(s), etc...

 

Ultimately, any amp can be considered for a home theatre application; however, not all will fit the bill. I'd recommend you focus your considerations on well reputed consumer and pro-audio brands, over that of commercial offerings, as there's also the 70-+ Volt thing, to be cognizant of...

 

If your still no further ahead that's because the answers is, it depend - on more variables than an on-line brother in arms can help you mitigate, in one exchange...

 

Thanks for throwing me a bone, in here.

 

Best regards,

 

GF

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post #6 of 109 Old 04-16-2014, 10:01 PM
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It is a shame to lose you Guy. You brought a ton of levity to the forum in your short stay. Take care and hope to see you again online.

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post #7 of 109 Old 04-17-2014, 04:37 AM
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Anyway - Moving on to my more direct answers...

Big question! The answers is, it depends.

Each of those brands that you mentioned, make reference audio products, pro-audio products and Crown also makes commercial grade products, and I know the Behringer is also entering this space as well, they might already be there...

As a general rule, commercial amps tend to be a bit noisy and often have somewhat limited bandwidths (for a couple of intentional reasons); however, that doesn't disqualify them, if the noise can be adequacy massed and the bandwidth fits the application. If you already own one such product, try it out.

Proaudio gear has a range of quality, and pricing... again, there is no reason why you could not consider using this category of product either. In fact, it is this category of amplification that is used in most move and stage acting theaters around the world, so your living, could also be a fit... Pricing and feature set is becoming a real tempter in this space. Peavey has a new line of D- Class amps, with on-board DSP, that weigh in at couple of Ibs starting at $300.00 - 2x 200 Watts - I'd have listen to that product for sure.. you can save a hundred bucks on drop the DSP...

Reference amps from any and all manufacturers seem to be the products of mainstream choice, for home theater buffs that decide to go the full pre-pro-amp path, if you will. Reference typically implies, that the series of product from a given manufacturer is near or at the top of their SQ options. You mentioned two brands, Alesis and Alesis, I mean Behringer... I've tested the A500 on a bench after several hour of ABX listing at my home and did discover a positive correlation between the two method evaluation. The A500 has a problem around 1Khz. A very audible and visual distortion, if you will; is present in them. I say them because I had two and both had the same short-coming. Outside of this, it seemed to be a great amp, = nice tone, adequate headroom, nice upgrade above most integrated offerings; and within the context of a home theatre application, could very well be a sensible fit. at $200.00, there's a lot left to like.I have not listened to or tested the Alesis. For critical listening in a 2-channel set up, the flaw forces me to have you look onward...

Over the years and recently as well, I have listened to and put a measuring device to many, if not most of the main stream models in commercial and pro-audio verticals; mainly because they're easy to come across and are often being more precisely calibrated and match to their respectively assigned pre-amp(s), etc...

Ultimately, any amp can be considered for a home theatre application; however, not all will fit the bill. I'd recommend you focus your considerations on well reputed consumer and pro-audio brands, over that of commercial offerings, as there's also the 70-+ Volt thing, to be cognizant of...

If your still no further ahead that's because the answers is, it depend - on more variables than an on-line brother in arms can help you mitigate, in one exchange...

Thanks for throwing me a bone, in here.

Best regards,

GF

guy Friendly,

Thank you for taking your time to explain things in great detail. From your description the alesis andbehringer will be out of the question. Distortion/anomaly in 1 kHz region is going to be too audible. Is there any other power amp can you recommend which won't break the bank? Unfortunately Parasound is no longer available in Canada as the distributor closed shop almost a year ago. I stated that I'm currently using Moon 330u power amp, but I personally feel that there should be a middle ground (in pricing) somewhere.

PS: i hope you will stay in this forum, but I wouldn't blame you if you decided not to. frown.gif

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post #8 of 109 Old 04-17-2014, 05:27 AM
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Quote:
Originally Posted by David Susilo View Post

Distortion/anomaly in 1 kHz region is going to be too audible.
Pity no measurements I've ever seen of the amp show up anything of the sort.

WRT pro amps, I've probably been using them at home longer than most here. I began using a triamped system with a triple set of Perreaux amps in the mid 80's. From that time and up until a few years back when I retired my PA system, I often used the amps in that system in my living room. I had access to a whole lot of domestic modest and expensive amps to compare them to during that time as well and they performed very very well in the comparison. Most of my comparisons were AB amps and I have little experience with class D pro amps (all my amps are class AB) though I have built a number of class D amps with Hypex, Ice and LC class D modules. The Hypex were the best of the D amps from that era.

I have a strong background in linear electronics and have designed and built many amps and have come to the conclusion that they are one of the least contributors to a system's sound, providing they are not clipping and set up and integrated properly. Used pro amps, especially class AB 'heavy' amps as they are being traded for class D/AB with SMPS that have similar power or more in a much lighter package. having humped my heavy rack in and out of many gigs, that is a huge advantage. It also often makes them excellent value in the market.
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post #9 of 109 Old 04-17-2014, 06:13 AM
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Quote:
Originally Posted by David Susilo View Post

I have a question actually. Since I've never used pro power amp for home use and vice versa, is there any advantage (or disadvantage) of using pro/commercial-grade amp such as Behringer, Alesis, Crown for home listening (especially two-channel audio) -- I currently use a Moon 330U power amp, System Audio Aura 30 speakers. XLO speaker wire (can't remember which model, but it's the one with 8 AWG.

The only common issue people report is fan noise. I have a Yamaha S3500 which I have tested in my home audio system. At normal listening volumes, the fan, which is heat activated, has never engaged so it is as quiet as a mouse. The specifications are all in the inaudible range. You can see the specs here. I think it is a great example of a pro audio amp that can serve as a home audio amp. You just have to deal with speakon and 1/4" connectors. I had a crown amp in my system many years ago and it was also quite suitable.
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post #10 of 109 Old 04-17-2014, 06:23 AM
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From your description the Alesis and Behringer will be out of the question. Distortion/anomaly in 1 kHz region is going to be too audible.

Interestingly enough results of the alleged ABX and bench testing were described with zero detail. Leads me to suspect that there was a concern that were not properly done, so all relevant facts were concealed to avoid the feared criticism.

Naive audiophiles seem to often be very risk adverse and even the most fragmentary and specious negative comment will distract them, especially when the fragement reinforces their prejudices.

This technical review seems to be exceptionally through and detailed and seems to report noting to be concerned about:

http://www.theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=22





4 ohm THD+N @ 180 wpc:




"Not that there is anything wrong these numbers; they indicate a completely transparent amplifier of considerable power..."

"There is no such thing as an effect without a cause, and there is no scientifically verifiable characteristic that would cause the A500 to sound different from any other amplifier that meets those criteria. The main reason why golden-eared audiophiles hear differences between amplifiers that do meet those criteria is that they don’t listen at matched levels. (Let’s not even bring up the more complicated subject of double-blind listening tests.) If one amplifier is just 0.2 dB louder than another, it will sound different, and therefore “better” or “worse.”

"No, sound quality is not the issue here. I am not going to give you quasi-pornographic descriptions of the bloom of the high strings on one CD and the plumpness of the lower midrange on another, as I listened to the A500."
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post #11 of 109 Old 04-17-2014, 06:30 AM - Thread Starter
 
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Pity no measurements I've ever seen of the amp show up anything of the sort.

WRT pro amps, I've probably been using them at home longer than most here. I began using a triamped system with a triple set of Perreaux amps in the mid 80's. From that time and up until a few years back when I retired my PA system, I often used the amps in that system in my living room. I had access to a whole lot of domestic modest and expensive amps to compare them to during that time as well and they performed very very well in the comparison. Most of my comparisons were AB amps and I have little experience with class D pro amps (all my amps are class AB) though I have built a number of class D amps with Hypex, Ice and LC class D modules. The Hypex were the best of the D amps from that era.

I have a strong background in linear electronics and have designed and built many amps and have come to the conclusion that they are one of the least contributors to a system's sound, providing they are not clipping and set up and integrated properly. Used pro amps, especially class AB 'heavy' amps as they are being traded for class D/AB with SMPS that have similar power or more in a much lighter package. having humped my heavy rack in and out of many gigs, that is a huge advantage. It also often makes them excellent value in the market.

 

Hello:

 

Yes, the distortion that I highlighted have been observed and documented by others, before me. Like you I was curious; so I bought a pair for $300.00, taxes in. I'm no fool - I can spot a deal so I bought them, and sold them for a small profit after I tested them. I would have kept them if it wasn't for the very obvious frequency error. Clears as day when viewing an FFT display. Standard THD sweep also evidences it. Once your ear-brain gets a hold of it, it becomes very distracting, at least in the application I was considering using them, which was a standard 2 ch. bi-amped configuration.

 

If you Google the A500, I am confident within 15-20 minutes that you should be well on the path to finding several other that have noted the same and a few objective postings depicting the occurrence, etc.

 

Thanks for you post.

 

GF

 

PS I here about the litter weight being a benefit in the market place...

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post #12 of 109 Old 04-17-2014, 06:40 AM
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Quote:
Originally Posted by A9X-308 View Post


Hello:

Yes, the distortion that I highlighted have been observed and documented by others, before me. Like you I was curious; so I bought a pair for $300.00, taxes in. I'm no fool - I can spot a deal so I bought them, and sold them for a small profit after I tested them. I would have kept them if it wasn't for the very obvious frequency error. Clears as day when viewing an FFT display. Standard THD sweep also evidences it. Once your ear-brain gets a hold of it, it becomes very distracting, at least in the application I was considering using them, which was a standard 2 ch. bi-amped configuration.

If you Google the A500, I am confident within 15-20 minutes that you should be well on the path to finding several other that have noted the same and a few objective postings depicting the occurrence, etc.

Are no such things that can be linked in a post,?

The above post can be taken as a tacit admission that in fact, no actual testing was performed. We are referred to unknown postings on the web, not the author's test results.

Or perhaps cutting and pasting is beyond someone's computer competence?

No, I'm not going to accept responsibility for supporting someone else's exceptional claims!
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post #13 of 109 Old 04-17-2014, 07:04 AM - Thread Starter
 
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guy Friendly,

Thank you for taking your time to explain things in great detail. From your description the alesis andbehringer will be out of the question. Distortion/anomaly in 1 kHz region is going to be too audible. Is there any other power amp can you recommend which won't break the bank? Unfortunately Parasound is no longer available in Canada as the distributor closed shop almost a year ago. I stated that I'm currently using Moon 330u power amp, but I personally feel that there should be a middle ground (in pricing) somewhere.

PS: i hope you will stay in this forum, but I wouldn't blame you if you decided not to. frown.gif


Hi Dave

 

I will PM you a list of amps that I would consider...

 

Take care,

 

GF

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post #14 of 109 Old 04-17-2014, 07:04 AM
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I don't get all of this about being banned and/or leaving for a few days because neither seems to be true.
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...


The power that be, keep deleting my posts and my threads, and have locked me out of from what I can tell, is any thread that has Arnold in. I guess they're trying to keep him from being embarrassed...

I would be honestly shocked if this post isn't also censored... I would be impressed if it isn't...I'll check back in a few days to see...

It was just starting to get interesting... Bummer! Egos & Icons and all that... I'm glad I'm not afflicted, with either.


I am a fan of debate and liked your responses in the original thread you participated in but these kind of comments I don't understand....You apparently have something to counter Arny with and it must be in one of those posts that the moderator deleted because so far it seems like a personal vendetta instead of actually talking about something. Seriously, if I missed it I apologize but I have to think that Arny has pissed the moderators off considerably more than what I've seen from you that hasn't been deleted and if not, don't make it so personal maybe all of us can gain from the knowledge you want to convey...Insofar as "kung fu, egos and icons" I just saw your post above this one and it seems you are TRYING to get banned by making it personal and giving the Mods no alternative, which makes me think this is more like the video game of Kung, Fu instead of the martial art.
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I don't get all of this about being banned and/or leaving for a few days because neither seems to be true.
I am a fan of debate and liked your responses in the original thread you participated in but these kind of comments I don't understand....You apparently have something to counter Arny with and it must be in one of those posts that the moderator deleted because so far it seems like a personal vendetta instead of actually talking about something. Seriously, if I missed it I apologize but I have to think that Arny has pissed the moderators off considerably more than what I've seen from you that hasn't been deleted and if not, don't make it so personal maybe all of us can gain from the knowledge you want to convey...Insofar as "kung fu, egos and icons" I just saw your post above this one and it seems you are TRYING to get banned by making it personal and giving the Mods no alternative, which makes me think this is more like the video game of Kung, Fu instead of the martial art.


Hi Zen,

 

Great comments, and I can see how it would appear that way. You are correct that I am being filtered. 2-3 other threads have been opened then shut down by AVS. and I am no longer permitted in David's thread, as AVS and not David has blocked me which, promoted me to open my own threads. This one is still open, but, in it I'm merely signing off and even still - they aren't allowing all of my posts...

 

You may never see this one, if I state much more...

 

The debate has become one sided, Arnold writes I read, I response, my reply disappears...

 

The Kung Fu is real...

 

I suspect that our paths may cross in another forum and you will recognize me, and read me unfiltered and join the Dojo...

 

regards,

 

GF

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post #16 of 109 Old 04-17-2014, 09:07 AM
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Originally Posted by A9X-308 View Post

I have a strong background in linear electronics and have designed and built many amps and have come to the conclusion that they are one of the least contributors to a system's sound, providing they are not clipping and set up and integrated properly. Used pro amps, especially class AB 'heavy' amps as they are being traded for class D/AB with SMPS that have similar power or more in a much lighter package. having humped my heavy rack in and out of many gigs, that is a huge advantage. It also often makes them excellent value in the market.
There is no free lunch in amplification as you know. If the unit is much lighter, then it has much smaller heatsink and the difference compensated by the use of a fan. The fan is not a problem in Pro applications but in this forum where almost everyone puts the amp in the same space as listening room, it can be objectionable on that basis alone.

The best use i have found for Pro amps is in driving custom/passive subs if the amp can be placed outside of the room.

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post #17 of 109 Old 04-17-2014, 10:40 AM
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Amir,
Just now I've got the chance to listen to a Behringer amp at local store playing back through the same speakers I use at home. I find the midrange (and higher) to be very harsh and fatiguing. As you know I'm in the camp of not everything sounds the same but at the same time I'm a super cheap bastard who is always hoping that the "everything sounds the same" for power amplifiers to be true so I can save money.

It seems like the cheapest amp (available in Toronto) that I find to be pleasing sounding come from Moon, Bryston and the, no-longer-available-in-Canada, Parasound. frown.gif

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post #18 of 109 Old 04-17-2014, 12:49 PM
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Quote:
Originally Posted by David Susilo View Post

Amir,
Just now I've got the chance to listen to a Behringer amp at local store playing back through the same speakers I use at home. I find the midrange (and higher) to be very harsh and fatiguing. As you know I'm in the camp of not everything sounds the same but at the same time I'm a super cheap bastard who is always hoping that the "everything sounds the same" for power amplifiers to be true so I can save money.

It seems like the cheapest amp (available in Toronto) that I find to be pleasing sounding come from Moon, Bryston and the, no-longer-available-in-Canada, Parasound. frown.gif

A potentially good example of hearing what is expected. I did some research into the technical problem, and there is a small problem but it has been grossly misrepresented in this thread.

There are some references to it on the web and all of the evidence points to this article as the best collection of relevance information related to it:

http://ixbtlabs.com/articles2/proaudio/behringer-a500.html

The problem that is reported all over the web probably traces back to this video from 2008:

https://www.youtube.com/watch?v=RWj5CUl7rio.

The video reports an apparently real irregularity but in a way that may make it seem more spectacular and signficiant than it really is:

"Shows significant harmonic distortion seen while turning the gain control through 60-70%. The amplifer's input gain stage is badly designed, according to our tests. It's ok at full power but do not trust any setting other than full. This means you must use the preceding system to control gain"

This is the reading of their THD analyzer at the point in their video where the operate the A500 volume control in such a way as to maximize the error:



You can see that the button for the most sensitive range is pushed. This means that anything over 0.1% THD pegs the meter. But 0.1% is right down there in the range that is in general inaudible, and only audible under very ideal conditions that are not at all like listening to music or even pure 1 KHz tones. So, yes there is a non-ideal condition that can be avoided by using only about 75% of the possible settings of the A500 input level control and avoiding the other 25% of the possible settings.

The problem is delineated more carefully in the first article mentioned above which is dated November 2, 2007 in the year before year the video was made.

I never experienced this in my tests because I followed the usual convention of setting the A500 gain controls to maximum and adjusted system gain elsewhere.

The actual source of the problem is not related to the quality of gain control potentiometer as one article claims, but rather the circuit design itself:



The problem is that the amp's input buffer circuit (based on IC28) is sensitive to variations in source impedance. These variations are a natural consequence of its use to attenuate and are maximized at - 6 dB gain, which just happens to be close the gain settings shown in the video and mentioned in the ixtlabs's article. It is possible that a IC with a FET input might avoid this problem.
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post #19 of 109 Old 04-17-2014, 12:52 PM
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Have you changed your name to Amir? i asked Amir a question, not you. Your input has no weight in my book.

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post #20 of 109 Old 04-17-2014, 01:00 PM
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Have you changed your name to Amir? i asked Amir a question, not you. Your input has no weight in my book.

Good thing that posts to regular threads aren't private and using threads for private communications is bad form. Ever hear of private messaging?

I suspect that there is more than one person is interested in this issue, which you may have implicitly agreed with by posting on a public thread in a public forum.
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post #21 of 109 Old 04-17-2014, 01:13 PM
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Amir,
Just now I've got the chance to listen to a Behringer amp at local store playing back through the same speakers I use at home. I find the midrange (and higher) to be very harsh and fatiguing. As you know I'm in the camp of not everything sounds the same but at the same time I'm a super cheap bastard who is always hoping that the "everything sounds the same" for power amplifiers to be true so I can save money.

It seems like the cheapest amp (available in Toronto) that I find to be pleasing sounding come from Moon, Bryston and the, no-longer-available-in-Canada, Parasound. frown.gif
Your findings make sense to me. Pro amps have a lot of power and driving bass is not an issue for them. The thing to listen to is mid to high frequencies.

Bryston would be a superb choice with fantastic warranty. I think it is something like 20 years which I suspect is far longer than one given by Behringer. And since they are local to you in Canada, it is even a better choice there.

Shame about Parasound. They are good amps with reasonably low prices.
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Thank you, Amir ! I guess there is no free lunch for amp design and in many cases you get what you pay for (excluding boutique audio, of course, in my experience they tend to be all over the place)

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post #23 of 109 Old 04-17-2014, 03:31 PM
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Have you changed your name to Amir? i asked Amir a question, not you. Your input has no weight in my book.
That's a shame as you're missing out on a wealth of knowledge and experience upon which to learn.

Assuming of course it's learning and not just confirmation of beliefs you're really looking for.
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post #24 of 109 Old 04-17-2014, 03:56 PM
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Thank you, Amir ! I guess there is no free lunch for amp design and in many cases you get what you pay for (excluding boutique audio, of course, in my experience they tend to be all over the place)

Hey David, I didn't know you were here, guess we don't frequent the same topics/threads, long time no "see". I am also a member of the "cheap bastard club" who can hear a difference between amps too. I think the power supplies of amps makes a big diff as to what you hear from them, and this of course also brings your local AC supply into the equation (usually uglier than one might think). IOW a "cheap" amp in one location could sound better than an "expensive" amp in another location with poorer power, if the AC is not well-conditioned. Similarly the load the amps are driving can bring out major differences, not to be noticed with most typical HT speakers which are intentionally easy loads for the intended market.

Now, when I really want to hear what an amp sounds like, I hook up a pair of old Stax 'stat phones (direct-connect to speaker BPs). They are an easy isolated load, with lower distortion and wider freq response and linear dynamic range than just about any speaker. You are essentially listening to the amp when everything else in the chain is the same. Not a fair real-world test because it's not your speakers and it's beaming right into your skull, but you can easily hear the differences between amps. Though it's the diff between preamps/pre-pros that really is much more significant IME (I love to compare pre-pros, all are welcome to bring!).

We are living in a good place to get some "not so cheap" amps. Within an hour's drive: NAD(/PSB) to the south (10 mins, in my town), Anthem(/Paradigm) to the west, Bryston to the east, Magnum Dynalab to the north. One thing that Americans might find odd that Canadians are used to: the gear made here usually/often costs more than it does in the U.S., a constant thorn to us. Maybe it's evened out a bit lately since the $CDN is low.
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NAD! Why didn't I think of that!!! Thank you cfraser. At the very least I can borrow NAD through Paul Barton to try the amp at home (he is a mentor and a friend).

Lately I seldom post because of the deluge of rude members who are taking away the fun from learning from each other but from now I'll be following your posts!

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post #26 of 109 Old 04-17-2014, 05:34 PM
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A potentially good example of hearing what is expected. I did some research into the technical problem, and there is a small problem but it has been grossly misrepresented in this thread.

There are some references to it on the web and all of the evidence points to this article as the best collection of relevance information related to it:

http://ixbtlabs.com/articles2/proaudio/behringer-a500.html
I was aware of the gain control issue before I posted last, but that was not the issue GF posted. After a bit of googling, I didn't see anything that backed up his assertion, but am happy to review anything linked in case I missed something.

The A500 is also easily modified to remove the GC issue which still makes it a good amp for relatively little money.

I think one of the most telling tests for amp 'sonics' was the infamous Nousaine Zipser test. Starts page pdf7.
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Originally Posted by David Susilo View Post

NAD! Why didn't I think of that!!! Thank you cfraser. At the very least I can borrow NAD through Paul Barton to try the amp at home (he is a mentor and a friend).

Lately I seldom post because of the deluge of rude members who are taking away the fun from learning from each other but from now I'll be following your posts!
Just a cautionary note that NAD has had serious reliability problems. It was so bad that they made some acronym out of NAD like "Not Always Dependable" or some such thing. They have supposedly improved their design and manufacturing now but no data on how much better it is.

We don't talk about it much but for me, the top factor for an amplifier is reliability, sound second! These things run hot, manage lots of current and are always stressed. It might be from repairing hundreds of them smile.gif. But I just think reliability and ease of service should be on top of buying criteria. For you guys up north, shipping things to and from US would be a pain. I know for us it was when we were dealing with Anthem/Paradigm. You have custom both ways and longer shipping time. So my vote would be to buy Canadian smile.gif.

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post #28 of 109 Old 04-17-2014, 09:11 PM
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Have you changed your name to Amir? i asked Amir a question, not you. Your input has no weight in my book.
You forgot that this is a public web site? Anyone can answer to any post on it. If you want privacy, PM people back and forth, don't post on public web sites.
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Yet another who thinks his name is Amir rolleyes.gif

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post #30 of 109 Old 04-17-2014, 09:42 PM
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Yet another who thinks his name is Amir rolleyes.gif
Not like I have a common name.... biggrin.gif
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