Emotiva Story.

You guys are a riot! lol ;)

Fred has over 30 years experince as a sound engineer...tried these on a whim...first one he turned on blew out......




John, Since you were there---

A copy of an e-mail I just sent -- enjoy

Fred

---

Dear Dan and Lonnie,

Thanks for the opportunity to try out the XPA-1's. I am in the process of packing all four of them for return. It appears I have the wrong speakers for the amplifiers. Further to our telcons, I have some notes and comments that you may find of value.

As I explained to Dan, who generously offered me good pricing as a return customer, I have been attempting to replace a high-power, high damping factor (over 10000) amplifier that I was driving two parallel Woofers with each of the L and R channels. It has been shipped to Japan and I now realize it was a mistake to have sold it. I was using bridged XPA-2's to drive the HF horns. The speakers weigh 300lbs each not including the separate crossover enclosure.

http://homepage.mac.com/dkoya/audio/k2m9500.html

After reading your XPA-1 description with reference to its superior control and limitless power and comments that it would "laugh at a 2ohm load", I believed that two xpa-1s should easily replace the single Crown Reference 1 that I sold to acquire the XPA-1's. When I unpacked and connected the XPA-1s to the woofer pairs, I was greatly dissappointed that the was intolerably loose, muddy and boomy. I couldn't raise the volume because energy remaining in the circuit was too highly annoying. The motion of the heavy woofers just wouldn't stop quickly and crisply. So I ordered two more, 1 for each woofer and was tri-amping, and beefed up the speaker leads to 4 conductors of 12awg from each amp. The result was an improvement but still far short of the control I experienced with the amp I was replacing. Although only 3 of four were operational, I concluded that four XPA1s still couldn't do it. There was an improvement in the midrange and imaging, but not enough to be convincing. It was obvious that an XPA-1 is definitely not the "control freak" as described in one of the publications.

I then tried other amplifiers. An $800 used Proceed HPA-2 stereo amp made by Levinson with a channel to each woofer sounded better than an HPA-1 on each woofer, but was still lacking in damping factor... Next, A pair of 20-year old Adcom GFA-565 monoblocks were tried because of their high damping factor of 800. The bass was noticibly tighter, almost as good as my original amp, but unfortunately they were rough and muddied the midrange.

Having proven that higher damping factor was key, I remembered that Lonnie once stated told me that damping factor for the XPA-2s was 500, not 200 as stated in the manuals. I then connected an XPA-2 with a channel each to a woofer. The bass tightness improved to a point somewhere between the XPA1's and the Adcoms as might be predicted according to damping factor. Of interest is that some re-equalizing was needed as seen on the spectrum analyzer before they sounded good. A further note is that extensive acoustic work has been done with the approximately 3500 cubic foot room with favorable hgt, width length ratios. so the room should not be considered an issue.

My latest information is that the XPA1-s have an internal resistance of 0.04 ohms with an 8 ohm load that translates to a damping factor of 200. When asked, Lonnie wasn't sure of this, which I found surprising. One of your web pages states the THD of the XPA-1 as 0.001 at full power from 20-20,000. The manual and bench tests implied a much different number. I concluded that is that it is not a good sign if the primary representaives of the company are not sure of either the published or other critical specifications. I had been rationalizing that this information might have been kept unavailable for competitive reasons.

Some quality control issues:

1-A rubber foot came off one unit when sliding it sideways on a shelf. Apply glue?
2-A trigger output failed to activate the next amplifier. Their sequence had to be rearranged. Add series resistor to prevent damage from shorting, in the event someone is reaching behind the unit to feel the opening with the tip of the connector?
3-One of the amplifiers smoked from its rear center when the amplifier was first switched on. Lonnie thought it was from the regulator board. Power on test?
4-A leftmost blue level indicator lamp on one of the three working units stayed on after the others were triggered off. It was erratic because it sometimes did stay off. I thought I noticed it once on one of the other amps. Perhaps it is set too sensitive and noise induction from the speaker wiring activated it.
5-The power cords were 18 gauge as might be found for desk lamps and clock radios. The plastic jackets were so brittle at low temperature that you might need to caution users not to flex them until they get to room temperature. When I saw this, I immediately re-wired for 240vac, as the Proceed amplifier with a similar kva rating had a 14 gauge cord.
6-The power connectors at the rear of the amplifers easily comes loose when the amplifier is shifted. Add a strain-relief outboard fastner that would hold the cord to the chassis? Permanently wire the cord inside, with a strain relief and grommet through the chassis?

There are some qualities that I applaud, such as the automatic ac voltage switching, optical isolation for the trigger inputs and the addition of the trigger outputs for repeating.

I know there are quality control issures with a new product, especially when manufacturing overseas. I appreciate the opportunity to acquire a quality product at an affordable price, as has been my experience so far. Might it be possible to sacrifice some phase alignment and other parameters and do some circuit tweaking to produce a separate model with high negative feedback? A damping factor upwards of say 600 or so, maybe 1000, to drive difficult loads and add some "woofer authority"?

At least you don't have as tough a job as Obama!

Thanks and Regards,

Fred K

NotaSuv wrote: »

Fred has over 30 years experince as a sound engineer...tried these on a whim...first one he turned on blew out......




John, Since you were there---

A copy of an e-mail I just sent -- enjoy

Fred

---

Dear Dan and Lonnie,

Thanks for the opportunity to try out the XPA-1's. I am in the process of packing all four of them for return. It appears I have the wrong speakers for the amplifiers. Further to our telcons, I have some notes and comments that you may find of value.

As I explained to Dan, who generously offered me good pricing as a return customer, I have been attempting to replace a high-power, high damping factor (over 10000) amplifier that I was driving two parallel Woofers with each of the L and R channels. It has been shipped to Japan and I now realize it was a mistake to have sold it. I was using bridged XPA-2's to drive the HF horns. The speakers weigh 300lbs each not including the separate crossover enclosure.

http://homepage.mac.com/dkoya/audio/k2m9500.html

After reading your XPA-1 description with reference to its superior control and limitless power and comments that it would "laugh at a 2ohm load", I believed that two xpa-1s should easily replace the single Crown Reference 1 that I sold to acquire the XPA-1's. When I unpacked and connected the XPA-1s to the woofer pairs, I was greatly dissappointed that the was intolerably loose, muddy and boomy. I couldn't raise the volume because energy remaining in the circuit was too highly annoying. The motion of the heavy woofers just wouldn't stop quickly and crisply. So I ordered two more, 1 for each woofer and was tri-amping, and beefed up the speaker leads to 4 conductors of 12awg from each amp. The result was an improvement but still far short of the control I experienced with the amp I was replacing. Although only 3 of four were operational, I concluded that four XPA1s still couldn't do it. There was an improvement in the midrange and imaging, but not enough to be convincing. It was obvious that an XPA-1 is definitely not the "control freak" as described in one of the publications.

I then tried other amplifiers. An $800 used Proceed HPA-2 stereo amp made by Levinson with a channel to each woofer sounded better than an HPA-1 on each woofer, but was still lacking in damping factor... Next, A pair of 20-year old Adcom GFA-565 monoblocks were tried because of their high damping factor of 800. The bass was noticibly tighter, almost as good as my original amp, but unfortunately they were rough and muddied the midrange.

Having proven that higher damping factor was key, I remembered that Lonnie once stated told me that damping factor for the XPA-2s was 500, not 200 as stated in the manuals. I then connected an XPA-2 with a channel each to a woofer. The bass tightness improved to a point somewhere between the XPA1's and the Adcoms as might be predicted according to damping factor. Of interest is that some re-equalizing was needed as seen on the spectrum analyzer before they sounded good. A further note is that extensive acoustic work has been done with the approximately 3500 cubic foot room with favorable hgt, width length ratios. so the room should not be considered an issue.

My latest information is that the XPA1-s have an internal resistance of 0.04 ohms with an 8 ohm load that translates to a damping factor of 200. When asked, Lonnie wasn't sure of this, which I found surprising. One of your web pages states the THD of the XPA-1 as 0.001 at full power from 20-20,000. The manual and bench tests implied a much different number. I concluded that is that it is not a good sign if the primary representaives of the company are not sure of either the published or other critical specifications. I had been rationalizing that this information might have been kept unavailable for competitive reasons.

Some quality control issues:

1-A rubber foot came off one unit when sliding it sideways on a shelf. Apply glue?
2-A trigger output failed to activate the next amplifier. Their sequence had to be rearranged. Add series resistor to prevent damage from shorting, in the event someone is reaching behind the unit to feel the opening with the tip of the connector?
3-One of the amplifiers smoked from its rear center when the amplifier was first switched on. Lonnie thought it was from the regulator board. Power on test?
4-A leftmost blue level indicator lamp on one of the three working units stayed on after the others were triggered off. It was erratic because it sometimes did stay off. I thought I noticed it once on one of the other amps. Perhaps it is set too sensitive and noise induction from the speaker wiring activated it.
5-The power cords were 18 gauge as might be found for desk lamps and clock radios. The plastic jackets were so brittle at low temperature that you might need to caution users not to flex them until they get to room temperature. When I saw this, I immediately re-wired for 240vac, as the Proceed amplifier with a similar kva rating had a 14 gauge cord.
6-The power connectors at the rear of the amplifers easily comes loose when the amplifier is shifted. Add a strain-relief outboard fastner that would hold the cord to the chassis? Permanently wire the cord inside, with a strain relief and grommet through the chassis?

There are some qualities that I applaud, such as the automatic ac voltage switching, optical isolation for the trigger inputs and the addition of the trigger outputs for repeating.

I know there are quality control issures with a new product, especially when manufacturing overseas. I appreciate the opportunity to acquire a quality product at an affordable price, as has been my experience so far. Might it be possible to sacrifice some phase alignment and other parameters and do some circuit tweaking to produce a separate model with high negative feedback? A damping factor upwards of say 600 or so, maybe 1000, to drive difficult loads and add some "woofer authority"?

At least you don't have as tough a job as Obama!

Thanks and Regards,

Fred K

Yeppers.

H9

the important thing is

Another milestone in Club Polk history:

I'm about to hit a milestone in my own personal Club Polk history, with 1,000 posts!


I wonder if i'll get a cookie (or maybe a "PIE")...:D

Lo siento Ricardo, no hablo espa

Kex wrote: »

I am sorry if it was I that offended you, Matt34, but I was somewhat irked by the elitist and dismissive tone you seemed to be taking with poster cnh.

I was having some sincere regrets about what might have been perceived as my harsh tone, especially when I noticed you seem to know both the revered cfrizz and Rt. Hon. Ron Temple (who are both far more "senior" to me here, since I am really mostly still but a lowly newbie) but then you went and ruined my contrite mood with this post:


I do hope you were merely in jest, and attempting to stick with the oft humorous tone of the thread, but sadly, by now you are most probably on F1nut's bozo list, which is not a good place to be, and which, I hasten to add, I am not (or at the very least, was not, when I won his most excellent karma recently). Oh well. Perhaps my initial response was justified after all ... ?

P.S. this really IS the most AMAZING thread, and I thought I was joking when I suggested it was headed for big one triple o!

My mistake was interjecting another point of view which appears is not acceptable here. It was not my intention to come across as "elitist or dismissive", it's hard to potray tone with written text. Howeve, I now realize that it's not welcome and I'm gladly going to move on and away.

My response to F1nut stands and I hope my request to the admins to remove my account is followed through.

My mistake was interjecting another point of view which appears is not acceptable here. It was not my intention to come across as "elitist or dismissive", it's hard to potray tone with written text. Howeve, I now realize that it's not welcome and I'm gladly going to move on and away.

My response to F1nut stands and I hope my request to the admins to remove my account is followed through.

Allow me to translate.....

He means his pants fell down while dancing and he is too embarrassed to continue posting here.

Tip: No need to ask for your account to be removed. Simply stop posting.

F1nut wrote: »

Allow me to translate.....

He means his pants fell down while dancing and he is too embarrassed to continue posting here.

Tip: No need to ask for your account to be removed. Simply stop posting.

You're persistent aren't you?

The majority of folk's who are new to a board try to ease their way into that particular forum's culture before spewing off at the keyboard. Here if one does, one WILL get hazed, but if one has thick skin and can show that they can contribute without pitching a hissy fit, they eventually find this place to be the best board around. Though there are close to 62k "members", it's a community of a few hundred.

Jesse can be one of THE most helpful and friendly people in CP, but he will put one through he gauntlet to prove one's worth when he feels the need or just get's that gut feeling that a troll has arrived. I for one am grateful that he does, because I'm not that patient and would get banned.

ND13 wrote: »

...if one does, one WILL get hazed, but if one has thick skin and can show that they can contribute without pitching a hissy fit, they eventually find this place to be the best board around.

Too true. I caught some crap for a little post called "Fancy Pants Forums" although I seemed to redeem myself after a couple of weeks and this ad :



If you take some time to try get a feel for this place, you'll find it's pretty cool with some very interesting members and views. Hell, I'm still a newb but I feel a little more at home every day.

Tim and ND13 are right,

All you have to remember is to cut the old-timers some slack...ha, ha...hey it's all cool. And it's only audio...that's why there is so much PASSION here!

cnh