XPA-1L

[maddog07]

OK… fellow audiofools… ;D any of you actually possessing a pair of XPA-1L’s – I’d like to hear your impressions. Like what do they sound like compared to ? And what is the context of the system you have them in, speakers, sources, etc.

[klinemj]

You do know there was an issue w the early batch and that they are getting reworked right now...right? Before any detailed reviews came out, the issue was ID'd and many that were in the field went back to Emotiva. Not sure if any are in the field right now. Emotiva announced they have a fix...not sure of timing, though.

Mark

[maddog07]

Nope... did not know that. What was the "issue"?

[klinemj]

Read the "XPA-1L Thread", starting at page 34. Main issue is that they are running a short period of time in Class A before kicking into A/B, even when load should be pretty low/nonexistent. Some also reporting an odd noise.

Within that thread you can also see Big Dan's comments along the way.

Mark

[maddog07]

thanks for the directions to that novel! Somebeach, I was so disappointed to read that Emo has launched another lemon. Do Not take me wrong here. I love Emotiva. I have owned and still own many Emotiva products. I've met the Emo gang at RMAF and on the road. Absolute Great bunch of folks! Customer Service beyond reproach... but that's just the point, we shouldn't need Customer Service "so much". Every Emo product that I've owned more than 6 months has been back for service at least once. I have an Emo sub that the amp has been out on twice.. it quits every 9 months so far. And this sub only sees use maybe once a week on average, at background music levels in a home office setup. My XPA-5 has been in for turn-on/muting relay issues, and well... we won't even open up the can of "bugs" of the UMC.
But I continue to support Emotiva with my wallet, because

• 1) great company,
  
• 2) great people,
  
• 3) product represents good value(when its working), and
  
• 4) I want to see them succeed so that we customers will continue to have more and more affordable toys and goodies to play with!
  

I first heard of the 1L in a podcast - kind of late, as I don't have the time to spend hrs on this forum everyday. But as soon as I finished listening to the podcast, I immediately went to the products page, and there it was. I of course looked at the pictures. And the very first thought that came to mind when I saw the picture of the inside of this amp, was; "that's not enough heat sink for two channels of 35 continuous Class A watts heat disipation without a fan". However, I'm not an electrical engineer either. But unless Big Dan has figured out some way to defy the laws of physics, that Poppa Pass and other great amp designers haven't figured out how to do yet, the 1L doesn't have enough "metal" to dissipate that much heat for long it appears to me. I have been pursuing this hobby pretty steady for over 30 years. And I once owned a pair of 25 watt Pure Class A mono amps, and they had at least 5 or 6 times the heat sink area of the 1L - and they ran "hot". They also did not have the "ability" to slide their bias down to A/B either like the 1L, so they had to have heat-sink for "worst case" scenario. As I understand how Class A transistor amps work, they actually run cooler when they are delivering the "load", i.e. the current to your speakers. And are actually, maximally, thermally stressed, when not connected to a load or playing music, i.e. all the current has to be dissipated as heat as its not being consumed by driving the speaker. Class A, by definition, means the transistors are conducting full on all the time. So.. play some music thru your 1L's at all times, and play it relatively loud!
Looks like I'll be sitting out on the sidelines of the 1L's for awhile yet until we see if this gets rectified by Emo - which I'm confident it will. But I'm wondering what the "actual" solution to this problem will be.... less class A bias ? less of the time?........ and not more heatsink/cooling capacity? But this is purely speculation.... so pay no mind - we'll wait and see.

[Boomzilla]

Hi Maddog07 -

The good news is that not everybody is as snakebit as you. The bad news is that some, indeed, are.

I agree that the apparent heat dissipation capacity on that XPA1-L amp seems meager for a class-A unit. Perhaps Mr. Pass was just being conservative on his design? Perhaps transistors have a wider thermal operating envelope now? I don't know.

I do know that ANY Emotiva recall gives the naysayers another "I told you so" opportunity. Big Dan understands this I'm sure which is why the long-awaited XMC-1 is still awaited. Emo doesn't want or need any more service issues.

In any case, I agree with you about supporting Emotiva with my wallet. When I can, I choose their products first.

[stiehl11]

Last time I bought a "lemon" it never worked. I thought that was the definition of what a "lemon" was. What they found (over a weekend of work) is that there was nothing wrong with the hardware of the units; so I doubt that anything will change there. They found that the firmware of the amp was corrupt and would have to be re-flashed. Considering the test that were done by those who posted here in the forum, if they change anything with the performance of the unit it will come out pretty quickly.

[maddog07]

I truly hope that is the case, because my favorite solid state amps over the years have been pure class A designs - Just like Lonnie says in the ad for the 1L. But not many speakers of recent are conducive to low-wattage pure Class A amps. At least not “main stream” speakers. Recently… I have been a convert to high-efficiency speakers, especially the full range, crossoverless ones… purity of tone and resolution of fine, low-level detail like I have never experienced by anything else – at any price. The past several years at RMAF, I have been completely seduced by the sound from these types of systems. Spending hours in these demos listening to my own music. I have never heard anything at any price that sounds more “real”. But these types of speakers do have their limitations and they do require very careful “matching” of amplification to speaker. SET tube amps are almost always used in these types of systems, with the exception of Pass’ First Watt ss amps – which are also magical in this regard(and very expensive). I am very anxious to hear 35 watts of “affordable”, pure Class A power from Emo on a Zu, Tekton, Cain & Cain, or basically anything based on a Lowther type drive unit, Audio Nirvana, etc.

Oh… and I guess I was stretching the def. of lemon there a bit… sorry. In my state, the lemon law is defined as: any default or condition that impairs the use, market value or safety of the product and the nonconformity has been subject to repair four or more times by the manufacturer or its agents, and the nonconformity continues to exist and the product has been out of service for 30 or more working days..... yada, yada, yada…. More legalease… so I stand corrected!

However, on the other hand, in over 30 years… I have only ever had to have exactly one(non Emo) audio component sent it for repair due to the product failing or not performing to spec – One – out of hundreds. And it was a HT pre/pro…. Undoubtedly the most complicated type of audio component any of us has ever owned. It had a video board go bad and display a green screen with blue lines running thru it… with pre/pro’s I almost expect issues sooner or later – just too much going on in there.

[jedinite24]

I wonder where the problem is occurring in the testing process for Emo. Shouldn't this problem with the XPA-1Ls been caught in QA testing or Beta testing? Does a sample of a batch get tested and then sent out for sale? I hope Emo gets through this unscathed. I was hoping they would have a hit with no issues with the XPA-1Ls.

[stiehl11]

Mar 29, 2013 16:07:22 GMT -5 jedinite24 said:

I wonder where the problem is occurring in the testing process for Emo. Shouldn't this problem with the XPA-1Ls been caught in QA testing or Beta testing? Does a sample of a batch get tested and then sent out for sale? I hope Emo gets through this unscathed. I was hoping they would have a hit with no issues with the XPA-1Ls.

From my understanding, the code was written, tested, and "released" for production. When the IC that stores the firmware was written to at the factory there was a "glitch" (a bit got turned or someone interrupted the code or something) and what was in memory was not what it was supposed to be. The fix is not new code but the correct code that was supposed to be there in the first place.

Now, as for C=0 sampling plans and AQLs, that is something that Emotiva has to decide on.

[1960broookwood]

Educate me please--why would a power amp run a PLC and firmware?

[stiehl11]

Ask Lonnie...

[brubacca]

Well if it is monitoring test points running in class a for a switch to class AB operation I could totally see it.

It is probably monitoring thermocouples and making evaluations based on temp for the switch. Can't think of anything else.

[LCSeminole]

Not sure why we have doubled up on a thread about the XPA-1L. The other thread has been on the front page of the "AMPLIFIERS" section for a few months, so quite hard to miss. Would everyone here prefer if I moved and combined this thread with the main thread?

[geebo]

Mar 29, 2013 19:17:08 GMT -5 LCSeminole said:

Not sure why we have doubled up on a thread about the XPA-1L. The other thread has been on the front page of the "AMPLIFIERS" section for a few months, so quite hard to miss. Would everyone here prefer if I moved and combined this thread with the main thread?

Works for me.

[stiehl11]

I don't see this is hurting anything... The other thread may be getting a little long in the tooth for some.

[milt99]

Maybe the mods could start a new thread titled:
XPA-1L: We heard there was a fix but we haven't heard anything since.

[maddog07]

Mar 29, 2013 20:54:35 GMT -5 milt99 said:

Maybe the mods could start a new thread titled:
XPA-1L: We heard there was a fix but we haven't heard anything since.

Now that would be constructive - and useful - yes please, yes let's do this!

[jheyau1]

Mar 29, 2013 15:18:29 GMT -5 maddog07 said:

thanks for the directions to that novel! Somebeach, I was so disappointed to read that Emo has launched another lemon. Do Not take me wrong here. I love Emotiva. I have owned and still own many Emotiva products. I've met the Emo gang at RMAF and on the road. Absolute Great bunch of folks! Customer Service beyond reproach... but that's just the point, we shouldn't need Customer Service "so much". Every Emo product that I've owned more than 6 months has been back for service at least once. I have an Emo sub that the amp has been out on twice.. it quits every 9 months so far. And this sub only sees use maybe once a week on average, at background music levels in a home office setup. My XPA-5 has been in for turn-on/muting relay issues, and well... we won't even open up the can of "bugs" of the UMC.

Thank you for sharing this information. I was thinking of getting a XPR-2, I'm leaning more toward the XPA-1L now for a couple of reasons--the 35W of class A power plus headroom of up to 500W in A/B mode into 4 ohms would really be enough for my 4 ohm, 99dB sensitivity speakers. The 1000W offered by the XPR-2 only give me 3dB extra max SPL but it doesn't have any refined class A power, and in case my unit needs repair, the shipping for the XPA-1L should be quite a bit cheaper than the XPR-2. BTW, do we pay for shipping both ways on repairs? I hope the XPA-1L will be ready on Emotiva's Chicago road show in a couple of weeks so I can take one home!

[ocezam]

Mar 29, 2013 15:29:23 GMT -5 stiehl11 said:

What they found (over a weekend of work) is that there was nothing wrong with the hardware of the units; so I doubt that anything will change there. They found that the firmware of the amp was corrupt and would have to be re-flashed. Considering the test that were done by those who posted here in the forum, if they change anything with the performance of the unit it will come out pretty quickly.

I hope that is all that is wrong. Several of us had sound issues that, so far, haven't been acknowledged. Only the class A problem has been recognized. On the other thread Keith said he thought the sound was interference from another component. Lonnie in an email to me said he couldn't imagine an amplifier making the sound I was describing.

Since both of my XPA-1L's had this "feedback" problem and an XPA-2 and two XPA-100's in the same system exhibit none of these problems, it leaves me a little concerned.