Kent even provided a tour of the factory and introduced the team assembling their gears. That was my experience when I picked up Pass items. If Kent has time, he would not mind doing that.
This One has Me Stumped
I recently purchased a Pass XP-12 to replace my aging ML 38s. After installation, I noticed gobs of high frequency distortion, especially in Operatic female voices.
I measured every component in the signal chain separately. All are performing in spec.The XP-12 has very impressive test results.
Re-installing the 38s gets me immediately back to more mellow sound.
In my system, I have an EQ and crossover between the XP-12 and my Bryston 2.5b^3 power amp. I removed the EQ and the XO, plugging the XP-12 directly into the power amp. The distortion remains.
I am puzzled. I am a measurement guy. I use REW extensively. I can measure and troubleshoot almost any problem in my system. This one is a stumper.
Can anybody suggest a measurement or a way to solve this apparent component mismatch?
My system in order from source to output :
Shelter 901 MKIII MC or Koetsu RS MC cartridges
Parasound Zphono XRM phono preamp
Technics SL-1200G TT
Oppo BDP-105 Universal player (digital)
Bryston BDA-3 D/A ( feeds the Oppo signal to the XP-12 or 38s)
Sansui TU-X1 tuner
XP-12 (38s) line amp
dBx 1231 EQ
Rane AC22 2 way crossover
Bryston 2.5B^3 power amp
Usher 604 floorstanding speakers
HSU ULS-15 sub (when using the XO)
Thanks,
Kevin
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- 27 posts total
I do not have experience with your models, but in general, and to refrain others: 1: Check the source out-put max voltage specifications to the pre-amp input specifications to assure tolerances are stacked. Adjust the output voltage accordingly if your phono pre or DAC permits such adjustments. 3: Tolerance stack output/input impedances source to pre and pre to power amp as well. I had an experience when I got my current integrated amp as a replacement to separates. My DAC XLR max output voltage setting exceeded the XLR max input voltage specification for the new integrated. This caused clipping distortion. Once I stacked and adjusted the DAC max output to the integrated max input specification, the clipping distortion vanished. |
@glennewdick intros a 'phile phenom we've encountered..... The Vulture...... "IF that's broke, can I have That?" *L* (....ready to catch what's tossed in frustration.... ;) ...) ..just teasin'... If Pass can't Rx the issue, @jsalerno277 seems to have an advanced routine that might cure.....👍🤞 Good variable factors..... |
@asvjerry Thou speaketh like you have an engineering or science background (variable factors). I, a quality engineer, Six Sigma Blackbelt, VPQARA, medical devices, retired. |
@jsalerno277 ....*L* No, more a background of having engineers design an 'enhancement' that drove fabricators and installers nutz do to the 'special tool' that didn't seem to hit the site with 'Gadget X'.....;)..... just jestin' *G* "Practical Magic" is more my experiential background.... |
- 27 posts total