phase linear 400
- Thread starter gene french
- Start date
Well here's an interesting development. I closed her back up and gave a listen. It appears to me that the right one is working just fine, but the left one is WAY oversensitive. The right one (the one that I thought was broken) is dancing between -10 and -20. The left one is constantly pegged.
Attachments
- Joined
- Jan 14, 2011
- Messages
- 74,216
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
The meters seem to be responding in synch with the music. They are steady at 0 (-20) on power on through the start of play back. Then when the music starts the left meter has a sweeet spot where if the volume is low enough (background music level), it appears to have accurate movement. It's a narrow sweet spot though. A little less volume and it stays put at 0. Normal listening levels (for me) have it bouncing off of the rev limiter, while the right channel seems to be responding accurately. It's bouncing so hard off of the right stop that I think that is the distortion/rattle that I was hearing last night.
I'm going to lower the sensitivity on the left meter as much as possible through the jumpers (which is the least sensitive setting?) and maximize sensitivity on the right meter and see if I can even them out a bit. I'm also considering running the amp on my bench with the meter outputs connected to my oscilloscope where I can see what the meters are getting fed. I'm assuming it's the meter, but who knows, maybe I have a output signal disparity between the two channels to the meter (both speakers have equal volume and soundstage/imaging is excellent).
I'm going to lower the sensitivity on the left meter as much as possible through the jumpers (which is the least sensitive setting?) and maximize sensitivity on the right meter and see if I can even them out a bit. I'm also considering running the amp on my bench with the meter outputs connected to my oscilloscope where I can see what the meters are getting fed. I'm assuming it's the meter, but who knows, maybe I have a output signal disparity between the two channels to the meter (both speakers have equal volume and soundstage/imaging is excellent).
My 400 Series 1 WOPL is a 8 fin with the Dixson meters. They're not very accurate, the 100 marking on the meter is supposed to represent 100 watts, not 100%. They do swing evenly, but I feel they really don't track power output well. This is why I prefer the Series 2 digital Cylon meters.
First thing to look for, is a meter stud contacting the copper buss bar or aluminum plate holding the storage caps? Joe was on same track.
First thing to look for, is a meter stud contacting the copper buss bar or aluminum plate holding the storage caps? Joe was on same track.
Overall, while I was not blown away with the bass response, I was impressed with the separation, clarity, and imaging that I got out of my short 2-3 song listening session. The dual mono setup is obviously a vast improvement over the separation I was getting out of my old Yamaha 70wpc amp.
Looking forward to acting on any suggestions you may have to help improve performance from here. I was going to swap cables and speakers tonight to see if there is any change. Looks like meter work will be my first order of business.
Looking forward to acting on any suggestions you may have to help improve performance from here. I was going to swap cables and speakers tonight to see if there is any change. Looks like meter work will be my first order of business.
