No difference with new XPA-100's

[robstl]

I have a Pioneer SC-1523-K AVR (Class D amp, manual states 135w per channel continuous for 9 channels at 1 khz, 8 ohms, .08%, and 220w per channel  at 4 ohms).  I have two Paradigm 9se MKII's rated at 150w at 4 ohms for my fronts, and five more speakers at 8 ohms (center and surrounds).

I added two XPA-100's to drive my Paradigms but I can tell no difference in sound quality or volume.  I re-calibrated, I've tried various volumes and material including concerts and movies but I still cannot tell any difference.

Can anyone advise why?  It seems to me this indicates the Pioneer produces sufficient power and clarity at high efficiency that the XPA's, even though they are rated at 400w at 4 ohms, can do no better.

[stads77]

I have always thoughts Amps generally sound the same, but speakers and preamps sound much different. Sometimes the speakers and preamps don't allow you to notice much difference, because their weaknesses trump the amps strengths.

Ben

[stiehl11]

What were your expectations?

[butchgo]

You might just give it a while just to see how the amps settle in.
I noticed a difference in my XPA-1Ls after 40-50 hours.
The seemed to kind of "open up".

[doc1963]

IMO, there's a couple of reasons why you (or anyone else) would hear no appreciable difference in your particular setup.

First, there would be only a marginal (3db at best) difference between an amp rated to deliver 220 watts and one delivering 400 watts at the same load. Depending upon your room, where you are in your room and the source material used for comparison, this very slight increase in headroom may or may not be a noteworthy improvement.

Second, you have "re-calibrated" your system which means the auto-setup of your receiver has done its job correctly. A "reference output level" (75db for example) would be the same perceived output volume regardless of the rated output capacity of the amplifier(s) used. The calibrated output voltage that the preamp delivers to each channel determines the output volume.

Last, since the SC-1523 utilizes digital amps, I would assume that the volume control also operates in the digital domain. If so, it's also likely that there is a "normalize" function that is used to limit the output voltage to avoid clipping the amps. The most noticeable indicator of this is the volume control perceivably "running out of steam" and gets no louder as the volume is increased beyond a certain point. In comparison, an analog volume pot in an analog preamp would deliver the full rated output voltage and, if overdriven, the amp would clip as a result.

It doesn't sound like you've done anything "wrong" and there's likely nothing that can be done to make it "better". The XPA-100's are excellent entry level mono-block amps, but their benefits, to you, may go unnoticed and under-appreciated.

As was previously suggested, give it some time and do some "critical" listening. Maybe you might notice some differences that you didn't notice before. Only you can determine if their presence in your system is a worthwhile improvement and worthy of the investment.

Hope this helps...

[creimes]

Mar 10, 2016 20:04:09 GMT -5 robstl said:

I have a Pioneer SC-1523-K AVR (Class D amp, manual states 135w per channel continuous for 9 channels at 1 khz, 8 ohms, .08%, and 220w per channel  at 4 ohms).  I have two Paradigm 9se MKII's rated at 150w at 4 ohms for my fronts, and five more speakers at 8 ohms (center and surrounds).

I added two XPA-100's to drive my Paradigms but I can tell no difference in sound quality or volume.  I re-calibrated, I've tried various volumes and material including concerts and movies but I still cannot tell any difference.

Can anyone advise why?  It seems to me this indicates the Pioneer produces sufficient power and clarity at high efficiency that the XPA's, even though they are rated at 400w at 4 ohms, can do no better.

The XMC-1 or XSP-1 will get you what your looking for, a good pre/pro or dedicated 2ch preamp makes a huge difference compared to a boxstore receiver, from what I have experienced anyway.

Anthem has a new pre/pro out now as well the AVM-60 which looks real nice

[Deleted]

No offense intended here in any way.  However, it is important to compare the amps in your Pioneer AVR to the amps in the XPA-100's on an even basis.  Note that the Pioneer AVR (SC-1523-K) weighs 33lbs (9 channels of amplification plus other functions of the AVR) and each XPA-100 weighs 27lbs for one channel of amplification including the box/frame.  Weight certainly is an important consideration in comparing components, especially the strength of the amp.

It is quite common for AVR's to list somewhat confusing amplifiers specs.  Emotiva amps, especially multi-channel amps list power with all channels operating simultaneously.  Here we are comparing an AVR with 9 channels and a mono block amp with one channel.  The Pioneer's confusing spec which you mis-stated is actually 760W at 8 ohms with 9 channels at 1% THD. This is actually 84 watts per channel with amplifier clipping.  This is a basically useless spec for you and is probably about 50 watts per channel or so at reasonable THD.  It might hit 70 watts with 7 channels or 80+ watts with 5 channels operating.  The legitimate spec is 134 watts per 2 channels operating with 0.08 THD which drops to 110 watts as I mention below with 0.04 THD. 

The XPA-100 is rated and then tested by Emotiva at 252 watts into 8 ohms with .012% THD.

For the actual Pioneer amp rating you have to read very carefully.  1% THD is considered as amplifier clipping (high distortion) and is not a comparable rate of distortion to compare to the Emo amp.  There are no ratings given for the SC-1523-K for all channels operating at less than clipping.  The reasonable power rating they list which is close to comparable to the Emo rating for the SC-1523 is (in the owner's manual) 110 watts with two channels driven into 8 ohms at 0,04% THD.  So we have a fairly honest comparison with very low distortion of about 252 watts versus 110 watts into 8 ohms.  Disregard any of the Pioneer amp specs with 1% THD or with only one channel.  Also the Pioneer amps have no ratings into 6 or 4 ohms at less than clipping.  What this means is that the Pioneer will most likely be OK with speakers in the 6-8 ohm range but when driving speakers hard that drop down to 4 ohms the amps might tend to heat up or even shut down, especially with all channels operating.  I couldn't find any reviews of the 9se MKII's and thus the Paradigm 8 ohms rating might be fairly close.  So you shouldn't have any issues driving 7-9 speakers unless at very high output for extended periods.

I only get into the above explanation to let you know the Emtovia XPA-100 is one beast of a mono block amp and puts out a legitimate 400 watts into 4 ohm speakers if you ever need it.

Of course the question for you is should you be hearing any difference?  Know that I'm one of the more skeptical members here about hearing significant differences in solid state amps under easy to normal playback conditions.  I feel you might occasionally hear small differences between the Pioneer AVR and the two XPA-100.  The better the sound source the more likely there might be an audible difference.  Most likely you will only hear a definite difference at very dynamic levels if and when you are nearing amplifier clipping on the Pioneer when the XPA-100's will still have 4-5 dB's of output left before audible distortion.  That would be very dependent on your listening habits, type of music or movies, output levels and your room size.  Watch out for one very common hearing misconception.  Many times with an amp that will start to distort with loud output the ears will tell us that is too loud, turn it down.  What is actually happening is the amp is going into clipping and we simply think it is too loud or as some folks says ear bleeding loud.  The same exact source played from an amp that has plenty of headroom left and does not distort will sound very loud but still clean.  In fact in tests it has been shown that in the two cases the output in decibels was exactly the same.  The case with the distorted amp made the listener thing the output level was actually louder when in fact it was the distortion that made it seem like it was louder.  

Just some food for thought.  Hope this made sense.      
 

[vcautokid]

Something good to know is that all Emotiva Amplifiers are rated all channels driven from 20hz to 20khz, or full bandpass. Another measure other manufacturers may use is 1khz only for their power rating. While valid, it is incomplete Measured full bandpass it would come out differently.

As far as difference I have to agree with the above posts that your calibration has done its job.

The short term dynamic peaks the XPA 100 amps will give will be impressive. Large power supplies, high current high voltage output devices deliver the impact and control your music and movies need. Also as your speaker impedance shifts relative to frequency, the current delivered by the XPA 100 will far exceed any AVR.

[rbk123]

Several thoughts and I'll try to be brief:
- I don't believe your Paradigms are sufficiently revealing for you to be able to hear a difference. You will need better speakers.
- I would not expect you to hear a difference on movies as the source material is not suitable for this. Focus on 2 channel music, especially since you are still using the Pioneer for everything else giving you a "hybrid" comparison for movies (vs. apples to apples).
- You still are using the Pioneer as your preamp which, imo, similar to your Paradigms is not sufficiently revealing. Unfortunately for you, you can't get a higher end preamp and use only the Pioneer for it's amplifier and then swap the XPA's in/out with it.

I don't see any real options for you, to be able to discern a difference on the XPA's vs. the Pioneer, *other* than to upgrade your mains and then swap the Pioneer/XPA's. If you switch to another preamp, you can't use the Pioneer's amp section only to compare against the XPA's.

[Deleted]

rarely is changing amps or power supplies going to yield an improvement

things you should do first before ever changing amplification to improve sound

1. upgrade speakers
2. properly treat your room
3. measure and eq your system properly

THEN maybe look at upgrading pre/pro then amps

[KeithL]

I feel obligated to suggest that any audio system is limited by its weakest link.

Perhaps the processor and preamp section of your receiver is the limiting factor.

[Lsc]

When I had the Onkyo 708 and Deftech speakers, adding a XPA-5 made a huge difference in my system.

If the XPA-100 didn't make a noticeable difference, I think the reason is as simple as that....the XPA-100 is not noticeably better than your receiver amps.

[brubacca]

I totally disagree with the comments on the quality of the speakers. They are good old speakers. Un less I am mistaken the immediate predecessor to the Studio series.

[garbulky]

First I dislike being told I am not hearing what I am hearing. So I think that you are actually hearing what you are hearing.
Imo you should notice some sort of difference. I have never preferred the amp sections or found them equivalent to even my UPA-2 when compared to recievers. Some things that could help.
Adjust your speaker positioning. I've almost always found that an electronics change required some adjustments to speaker positioning to sound its best. Do this with calibration off. Then calibrate. But try comparing between the two before you recalibrate.

I found it harder to hear component differences without any kind of acoustic treatment.
This might help a lot. Best value for the money imoprovement I have done (minus speaker positioning.).
Even one behind the couch helps at head level. More is better.
www.atsacoustics.com/item--ATS-Acoustic-Panel-24-x-48-x-2--1001.html

[monkumonku]

My feeling is the reason you don't hear any difference is because your ears are not resolving enough your speakers are not resolving enough you're not trained in listening there IS no audible reliably consistent difference.

If you're using your gear within its rated specs that isn't taxing the amps, then why should you hear any difference?

That said, my suggestion, if you are switching back and forth trying to hear a difference, is instead to just sit back and enjoy some music for an extended listening session using the new amps and then with the old amps. And see if you prefer one or the other. The difference may be subtle but your brain may be processing it to steer you towards one versus the other though you can't readily identify why. If you do this and still don't feel there is a difference, then I'd say your hearing and judgement are perfectly fine.

[mshump]

When I added an Amp off my old Onkyo receiver I heard almost no difference in Movies and HT, but with music it was more of a fuller sound. Try some music and listen if it sounds a bit better.


Mark

[robstl]

I appreciate all the responses. After reading numerous articles about separates, I started thinking I was missing out. I was expecting to hear richer/fuller/bigger sound. I am aware that specs listed my AVR manufacturers are misleading and/or incomplete. I'll give them some more time, and switch back to using just the Pioneer amps to see if I can hear a difference.

[cheapthryl]

Try some room treatment or might be time for new speaks.