Pass Labs x250 stopped working shortly after buyer got it. What to do?

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If that was the case, that would support the "shorting the output" theory. Only Johnny knows.

Jason, please provide details as to how you damaged your X250. It might help resolve the issue.
 
In general if a fully functioning unit was shipped but a faulty one received I would immediately contact the shipping company to claim responsibility. Further investigation shall reveal what and why is the issue.
 
I want to take this moment to apologize to everybody on ML forum and especially to Tom of my ignorance and stupidity and a lack of knowledge in electronics general. I really made a big mess and created a whole scenery on here and devalued Tom's integrity over my ignorance.

After staying up until 3 in the morning switching and swabbing different components and trying to figure out all the possible ways of what was wrong with the amp, found out that one of my brand new, just received, RCA cables wasn't work. Who would thought of a brand new cable don't work? Well, I did. Oh my my, I did make a mess. Everything working fine now when I changed a different RCA cable. You all can curse me out or do whatever you want to, I am taking a full responsible for this. But anyways, I am happy and relief as hell.

So to sum it up, I am sorry to all. Tom, I don't know what else to say but I am truly sorry man. My over-excitement has created a whole mess when things don't go right.
 
Hi Johnny... I am so glad to hear that you found the problem and that the amp was indeed working. Apology accepted... YAY!

So... how do the Odysseys sound now??? Should be awesome.
 
Hi Johnny... I am so glad to hear that you found the problem and that the amp was indeed working. Apology accepted... YAY!

So... how do the Odysseys sound now??? Should be awesome.

Thank you so much Tom for accepting my apology. Amp works great but the sub still sound like it cracked when the volume is loud. Mid and high don't sound clear when volume is high so I dont know
 
in a curious twist to this whole story, after I shipped the amp to Johnny, i connected my Summits to the X5... somehow, some way, the center channel was crackly and not functioning correctly.. not sure what I did, but I contacted Pass who said it would probably be an easy fix since the channel isn't completely dead. I connected the center channel from the processor to one of the rears on the X5 and used that as the center channel and left the rear un-connected, figuring I would wait till after the holidays to send the amp in for repairs.

Yesterday i was watching a movie and the amp suddenly stopped working.... completely. faint smell of burnt electronics wafted up from it, so I unplugged it all and am boxing it up this morning and sending it in for repair, which may or may not be expensive.. We'll see.. Finished watching the movie with just the speaker in the TV.. OMG.. what a difference.
 
Johnny,

That happened to me once. Verifying functionality of a new interconnect would be one of the LAST THINGS I WOULD CHECK.

In my mind, totally understandable.

Hope all goes well in the future and that you are not attacked by any more "audio demons".

Gordon
 
I'm glad you've worked out the main issue, but now we figure out why you're getting distortion at high volume. Do you have another pair of loudspeakers you can try? They don't have to be great speakers, just need to be known to be good. In addition, can you tell me what Preamp you're using? You could have discrepancy between the output voltage of your preamp, and the maximum input voltage on the X-250.5
 
Thank you for understanding all. All I have in speakers now is my old Boses but in a few day I will receive the frescos. I'm using a krell showcase as a preamp
 
Thank God this issue is over before Christmas, New Year and more importantly before Tom's and Roberto's birthday. Had the potential to ruin occasions of happiness.

Lesson learned is not to shoot first and ask questions later.

Julian was right earlier on to suggest trouble shooting.
 
Johnny, have you taken a moment to read the owners' manual yet?
https://passlabs.com/images/uploads/manual/x250_5-om.pdf

It sounds like you're using Single Ended interconnects (RCA Cables), so depending on what type of interconnects Tom was using, you may need to install jumpers on the Balanced Inputs (XLR connectors). Read the whole manual, but take a close look at page 5, which details the jumper installation.


Notice the section on Toms' Associated Electronics, namely the Audioquest King Cobra Interconnects, which are XLR. Are the jumpers installed in the XLR connectors on your X250.5?

System #01 (Summit, Cinema)

1. Member Name: Tom D.
2. Location: Hayward, California USA
3. ML Model(s): Summit & Cinema
4. Year Purchased: 2008, 2003
5. Mods/Changes: Speltz Anti-jumpers

6. Associated Electronics:

Anthem Statement D2 Pre/Pro with ARC
Pass Labs X5 Power Amplifier
Belkin PureAV Silver Series speaker cables
AudioQuest King Cobra Interconnects (XLR)
Slim Devices Squeezebox 3 feeding into PS Audio Digital Link III DAC
Oppo BDP-83 BluRay / SACD / CD / DVD player
DBX 4BX Dynamic Range Expander
Hughes HD DirecTV Digital Network Recorder (TIVO)
LG 55LE8500 55" LED TV
Klipsch Quintet Surrounds (not shown)
Panamax M5300-PM Power Conditioner
OmniMount Cosmic Video Stand
OmniMount Cosmic Audio Tower
VTI Amp Stand
 
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you may need to install jumpers on the Balanced Inputs (XLR connectors).

Julian,

Assuming you are talking about the "amp shorting pins" on the XLR "input" connects, a good idea to have but not critical. It does lower the noise floor and is recommended.

If Johnny needs them, he can contact Pass and I'm sure they will provide the two pins with a diagram on how to install. Johnny, if you do this, remember to turn the amp off using the rear switch and wait a few minutes until the amp power supplies totally discharge.

In a "typical installation" (amp right speaker connect to right speaker and left to left), "jumpers" are typically installed on the speakers, not the amp.

Gordon
 
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Well since I was having trouble with the interconnect, I m using XLR now but the distort is still there. I don't know if configure the preamp would help but I'm also having difficulty on getting into menu control on the showcase, it called the on screen monitor (OSD). Seem like I'm having all the problem right now but at least got the amp problem out of the way. On the XLR, I'm using just regular ones was used for my PA speakers. I'm waiting to receive a new ones "Better Cable Silver Serpent XLR) and will see if it any helps
 
I'm just thinking that the output voltage from your preamp may be too high, thus manifesting itself as too much input gain. I had that problem with a DAC that has an output voltage of 4.5 volts to my A-S2000 which is limited to 2.0 volts. Sounded awful. I couldn't find the specs for your Krell, but it may be adjustable.
 
If that was the case, that would support the "shorting the output" theory. Only Johnny knows.

Jason, please provide details as to how you damaged your X250. It might help resolve the issue.

I had the amp on and was swapping cables around and shorted them. Not a noise but instant smoke and nasty burnt smell.
 
So regarding the distortion, I tried on a pair of Fresco today and it get even worse. Does the Fresco too small to handle it? Does anybody know what the problem there? Preamp? I am gonna borrow my brother's speakers, bose 901, to try it tonight to see.
 
Check the output impedance of the Krell and the input impedance of the Pass (different with XLR's - 22K ohms versus single ended -12K ohms) ratio. Your preamp may be over loading the amp, as Julian suggested.

The accepted ratio is a minimum 10 to 1 (amp - preamp). Based on this, your Krell output impedance should not exceed 2,200 ohms if using single ended and 1,200 ohms if using balanced.

Hope that helps.

Gordon

PS: There's an easy / inexpensive solution if this is the problem.
 
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Hola. You could be using the phono input section of your preamp with your cd, and the distortion is coming from the saturated input. Use aux, tape or tuner input, not phono. Just guessing what it could be the distortion.
 
Thanks for the inputs guys. What I did was I went into the krell and lower the input level from the dvd device which I play music with (There is no output level option to amp in the krell) and switch to -3db in bass control instead of flat and I was able to turn it up louder with no distortion. I mean louder is you don't wanna sit there to listen to it for a whole song, it definitely will damage your hearing. But I try to crank it up a little more louder, then the distortion is still there. I don't know if I expect too much out of it or it not suppose to have any distortion at all don't matter how loud you play? Is it a dump question guys? Also, the sub no more popping if I have it in -3db mode in bass control. Do you guys think if it has anything to do with the internal power supply board?
 
If you play nice and quiet does it still distort?
 
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