Natural Sound
Active member
I was digging through some old Valve magazines and reading about the development of the original S.E.X. amp. That was a lot of fun. It also nudged me into dusting off a S.E.X. 2.1 amp I had sitting around and putting it in service.
I performed a quick resistance and voltage check. Then I hooked up to a pair of Blumenstein Orca's and fed it with my DAC. I could tell right away that something was wrong. There was very little bass and and no sound-stage. I have a stereo test FLAC file on my music server that tests L/R Channel and phase. I ran that and the result was that the system was out of phase. So I swapped the + and - on the right speaker and ran the test track again. The phase was corrected but when I played music something still wasnt quite right. So I put the right speaker back the way it was and repeated the sequence on the left. Swapping the + and - on the left speaker fixed the phase and now when I play music it sounds beautiful. The Orca's image right up, bass is as good as an Orca's can provide by themselves. I have dual Orca subs but I havent introduced them into the system yet.
The speaker phase on the left channel has me bugged. I'm wondering if I have a miswire in the S.E.X. amp or in the speaker. Can I use a small 1.5V battery to check the polarity of the Orca without harming the drivers? I kind of remember someone mentioning trying that.
Once the amp cools down I'll flip it over and verify my wiring from OT-2 to the headphone jack and back to the speaker terminals. Is there anything else I should check?
My OT-2 is configured for 8 ohms. I doubt that makes a difference but I thought I'd mention it.
The wiring check is going to have to wait until I finish listening to a 24bit 96kHz high resolution recording of Steely Dan - Countdown to Ectacy.
I performed a quick resistance and voltage check. Then I hooked up to a pair of Blumenstein Orca's and fed it with my DAC. I could tell right away that something was wrong. There was very little bass and and no sound-stage. I have a stereo test FLAC file on my music server that tests L/R Channel and phase. I ran that and the result was that the system was out of phase. So I swapped the + and - on the right speaker and ran the test track again. The phase was corrected but when I played music something still wasnt quite right. So I put the right speaker back the way it was and repeated the sequence on the left. Swapping the + and - on the left speaker fixed the phase and now when I play music it sounds beautiful. The Orca's image right up, bass is as good as an Orca's can provide by themselves. I have dual Orca subs but I havent introduced them into the system yet.
The speaker phase on the left channel has me bugged. I'm wondering if I have a miswire in the S.E.X. amp or in the speaker. Can I use a small 1.5V battery to check the polarity of the Orca without harming the drivers? I kind of remember someone mentioning trying that.
Once the amp cools down I'll flip it over and verify my wiring from OT-2 to the headphone jack and back to the speaker terminals. Is there anything else I should check?
My OT-2 is configured for 8 ohms. I doubt that makes a difference but I thought I'd mention it.
The wiring check is going to have to wait until I finish listening to a 24bit 96kHz high resolution recording of Steely Dan - Countdown to Ectacy.
