114 replies to this topic

[frozenpod]

bassett, on Dec 21 2010, 08:23 PM, said:

IT sounds to me like your Amp isn't putting out the  wattage it's supposed to do.  Distortion is normally a sign of  under-powered
amp's.   Rule of  thumb,, Higher the wattage output, lower the distortion.  And if your running  easy driven speakers [8 ohm ]
It might not be noticeable, until you wind up the volume, till your ears bleed  But try hooking up some  4 ohm, or if you want to
convert it to a a smoke machine, try a  2 ohm load. or a pair of electrostatic's.

Thanks for your input but I have to say this looks like a troll post....

Since I have come this far I will play.

The amp is no where near clipping and isn't producing louder sound levels than achieveable with a 100W amp which was well under its maximum possible power. The sound levels should not have been stressing the amp shouldn't have been close and would be easily repoduceable with a 40-60W amp.

As you wont believe this my wife and I don't see a lot of movies in the cinemas as she thinks they are way too loud and often has to cover her ears she had no issues with the sound levels used for testing.

bassett, on Dec 21 2010, 08:23 PM, said:

It should drive the 4 ohm speakers,  but turn up it's toes at 2 ohm,  Just perhaps these things have an over rated output, or
the power supplies are just not up to the job,  And lets face it, your not going to get quality, at the price there selling there
mass-produced products for.  And the way there selling,  Mass'productions costs are more then likely  somewhere between $20 and
$50 per unit.

The UPA-5 has an underrated power supply, the XPA-5 has from the specs and full rated power supply using a 1200VA Tx.

As to the price $20 -$50 per unit not sure what your point or reference is too. $20-$50 cost per XPA-5 or $20-$50 per channel.

We currently produce a audio amp not used to drive a speaker but to produce a high quality sinewave into a 2ohm load of a variety of frequencies. In bulk manufacture the cost of the power stage excluding power supply and preamp is just under $40 (including a small heatsink not rated for continuous operation) for a single channel. As per my other post the costs in an amp are the power supply case and heatsink, the power stage is one of the cheapest components. Hence why there is no reason emotiva couldn't improve there amp and produce audiophile sound quality for a very similar price.

PS high power amp using a high rail voltage is harder to design to produce an inauidable noise floor and inauidable distortion whilst your general rule of thumb somewhat applies only if you are running at a lower % of rated output power you will be less likely to run into issues distortion by over stressing the amp.

[frozenpod]

So long and thanks for the, on Dec 22 2010, 02:23 PM, said:

PS : I have had the pleasure of listening to a couple of pairs of Osborn speakers and I do like their sound but I would say they tend towards the brighter more forward end of the spectrum and so imho would not be suited for use with a ht style power amp.

Interesting comment.

I have read a number of speaker reviews recently and reviews there the review commented on the speakers being overally bright often had a very flat response where as speakers which were lacking in the top end according to there response were described as being more natural and smoother.

Thus often what people are used to is speakers which don't have the correct reponse at the top end and when you hear a speaker which does they tend to sound overally bright at first.

[frozenpod]

treblid, on Dec 21 2010, 06:21 PM, said:

So what you're hearing is not "SSssssssssssssssssssssssssssssss" (can't really describe it in words - think of it like fingers on the chalk board)?  Think I have asked you this many times, not sure if you have responded?

I know what you are refering to and no this isn't the issue.

treblid, on Dec 21 2010, 06:21 PM, said:

You resort to measurements from what I think is a different XPA-5 unit to back your claim, but what you have done is just to confirm that the XPA did not work well in the system you tried. i.e. It lacks the mystic synergy..  or maybe you are right that the XPA-5 is really not that good...

It's not the conclusion you made I have a beef with, it's the approach, it seems incomplete for some reason...

Not that you are right and I am wrong, or vice versa... It's that we are all horribly out of sync with each other.. You say good sound, poor sound... That's pretty subjective, and with no reference baseline on what your idea of good or bad is - it's real hard for me to understand where you're coming from (forum is a really bad way of communication)....

Hence the reason why I ask you to describe the distortion, is it the one I described, or something else entirely, just so we can establish a common ground.

Ps: I'm only here coz my work server is extremely slow.. When the migration to the new server is complete (12 cores with HT, that's 24 threads!!!!), hopefully I will be as bz as you are... That's my excuse for the christmas month and I'm sticking to it..

The approach was very good a controlled back to back test if you would like I could look up a speaker cable review and insert some big words but they are little value other than to sell magazines and not flat out say an amp is bad.

As per my other posts after seeing the full detail report and FFT it certainly backs up my experience which I have already posted on (I thought I already posted on what the distortion was).

[frozenpod]

jliang70, on Dec 22 2010, 08:00 PM, said:

I did listen to my friends Osborns a few years ago and it was running with my older 300B amp it was good but it wasn't the type of speaker that I want to listen for long time, they sound a bit cold and musically uninvolving comparing to my tannoy.

Probably because the osborn speakers produced very lower THD compared with colour and inaccurate reproduction speakers you are used to.

[myrantz]

frozenpod, on Dec 23 2010, 06:00 AM, said:

I know what you are refering to and no this isn't the issue.

That's good then.

frozenpod, on Dec 23 2010, 06:00 AM, said:

The approach was very good a controlled back to back test if you would like I could look up a speaker cable review and insert some big words but they are little value other than to sell magazines and not flat out say an amp is bad.

As per my other posts after seeing the full detail report and FFT it certainly backs up my experience which I have already posted on (I thought I already posted on what the distortion was).

Not sure if you have actually describe the distortion in better detail.. If you have I must have missed it.. But if your experience says you are correct, then in your mind it has to be correct and there can be no other possible outcome.

frozenpod, on Dec 23 2010, 06:02 AM, said:

Probably because the osborn speakers produced very lower THD compared with colour and inaccurate reproduction speakers you are used to.

troll bait?   As mentioned don't really know much about 'em so can't take it unfortunately. But I do like the way they  look ...

I like distortions, esp when it's unexpected.... Day by day I think I'm morhping into an subjectivist...    Anyway I'm out of this thread.. Enjoy guys...

[frozenpod]

treblid, on Dec 23 2010, 11:38 AM, said:

But if your experience says you are correct, then in your mind it has to be correct and there can be no other possible outcome.

Very true in terms of my opinion we are all human after all.

treblid, on Dec 23 2010, 11:38 AM, said:

I like distortions, esp when it's unexpected.... Day by day I think I'm morhping into an subjectivist...    Anyway I'm out of this thread.. Enjoy guys...

Lots of people do, plenty of people love ribbin tweeters because they introduce nice distortion.

IMO audio system at home is a reproduction system not a musical instrument thus is should not introduce harmonics that was not in the orginal recording.

[jliang70]

frozenpod, on Dec 23 2010, 09:02 AM, said:

Probably because the osborn speakers produced very lower THD compared with colour and inaccurate reproduction speakers you are used to.

I did not really care about the measuring THD on either speakers or reading how they measured in term of THD.  Tannoy manages to produced a much more detailed sound than the Osborn I heard and also sounds more musically involving with far bigger sound stage. It is probably an unfair comparison Osborn I heard was probably about $7000 and Tannoy was more expensive.

[frozenpod]

jliang70, on Dec 23 2010, 01:13 PM, said:

I did not really care about the measuring THD on either speakers or reading how they measured in term of THD.  Tannoy manages to produced a much more detailed sound than the Osborn I heard and also sounds more musically involving with far bigger sound stage. It is probably an unfair comparison Osborn I heard was probably about $7000 and Tannoy was more expensive.

Speakers certainly do perform and sound differently even if they are the same basic test measurements such as frequency response.

I am more than happy to take your word that you prefer your speakers to Osborn's although your comments do tend to indicate the Tannoy speakers have produced greater levels of harmonics.

[ozcal]

frozenpod, on Dec 23 2010, 05:54 AM, said:

Interesting comment.

I have read a number of speaker reviews recently and reviews there the review commented on the speakers being overally bright often had a very flat response where as speakers which were lacking in the top end according to there response were described as being more natural and smoother.

Thus often what people are used to is speakers which don't have the correct reponse at the top end and when you hear a speaker which does they tend to sound overally bright at first.

Understandably you discount the fact that I have been in hi-end Audio retail and as a hobbyist for the best part of 3 decades as you would have no way of knowing my background.

At home I use a variety of speakers including Gale 401a's , B&W703'S and various Tannoy DC'S.Over the years I have probably heard 100's of brands over extended periods in many locations so I reckon I have a fairly good idea of what constitutes a 'correct' response.
As I said Iliked the Osborns

[DarrenW]

frozenpod, on Dec 23 2010, 08:51 AM, said:

Thanks for your input but I have to say this looks like a troll post....

Pot............ Kettle.............. Black...............

[jliang70]

frozenpod, on Dec 23 2010, 04:04 PM, said:

Speakers certainly do perform and sound differently even if they are the same basic test measurements such as frequency response.

I am more than happy to take your word that you prefer your speakers to Osborn's although your comments do tend to indicate the Tannoy speakers have produced greater levels of harmonics.

Just like any piece of audio equipment it is a personal thing.  I think the partnering equipment of valve amps and cd player also played their parts as they may favour the more valve friendly and efficient Tannoys than Osborn.

Edited by jliang70, 24 December 2010 - 10:19 AM.

[bassett]

frozenpod, on Dec 23 2010, 08:51 AM, said:

Thanks for your input but I have to say this looks like a troll post....

Thanks for the insult,  and a Merry Christmas to you to.

But it would seem you have successfully changed the subject in the thread,  well done, and thanks for coming..

But should you feel the need to discuss the merits of "Osborn" in another thread I'm sure there
are people here that will only be to happy to contribute.  I for one will have no trouble in bursting your little bubble.

Having said that, Nothing further needs to be said.

[frozenpod]

bassett, on Dec 24 2010, 11:30 AM, said:

Thanks for the insult,  and a Merry Christmas to you to.

But it would seem you have successfully changed the subject in the thread,  well done, and thanks for coming..

But should you feel the need to discuss the merits of "Osborn" in another thread I'm sure there
are people here that will only be to happy to contribute.  I for one will have no trouble in bursting your little bubble.

Having said that, Nothing further needs to be said.

My comments were not an insult just an observation as you received them as an insult I appologies.

[dean70]

I am looking to buy an XPA-3 & noticed that the IEC power connector only has a 2 pin plug. Would this cause any issues with hum, ground loops, etc?

I would have thought an earth connector would be mandatory (for the above reasons, as well as safety).

Edited by dean70, 26 May 2011 - 02:07 PM.

[GaryCook]

dean70, on May 26 2011, 02:07 PM, said:

I am looking to buy an XPA-3 & noticed that the IEC power connector only has a 2 pin plug. Would this cause any issues with hum, ground loops, etc?

I would have thought an earth connector would be mandatory (for the above reasons, as well as safety).

Class 2 appliances are made in such a way that they need no earth because there is little chance that the user will ever be exposed to 240V ie; they  are double insulated and so don't require an earth pin.

Earth loop wise I haven't experienced that problem with HiFi gear for 20+ years, my cousin's Emotiva gear included.  He also has an XPA-3.


Cheers
Gary

Edited by GaryCook, 26 May 2011 - 03:40 PM.