Two tweeters went bad in 2 days
gmcman
Posts: 1,806
in Electronics
At first I thought this was possibly an accident with regards to myself and probably the kids...still might be but not so sure now. My 2B TL tweeters (RDO-198) sounded slightly thin and just ever so slightly grainy on the top end a few days ago but nothing too serious however I sensed something was amiss.
I played them loud a few times, not ear-piercing but kinda loud, no distortion or woofer popping loud and all was fine. Not too long ago my kids were setting up the game console and had the Ref 50 on CD so while searching for sound, they turned it up then changed inputs without turning the sound back down....it was pretty loud and could have compromised something.
Fast forward to yesterday and my left tweeter was out. I had a replacement handy and swapped it out then all was good, the slightly harsh highs were gone. Today I went down to listen to a few CD's and the left tweeter was gone again...
This time nothing was on except for the amp.
I did recently acquire a tube preamp which I've been trying a few different tubes which is why I'm doing some A/B testing and swapping back and forth to my Ref 50. The only thing that might be an issue is I turned the amp (B&K 200.2)off before removing IC's then swapped RCA's, when I turned everything back on, I had a buzz from what would appear to be a loose RCA but they were secured into the REF 50, then I quickly turned the amp off again. After I reseated the RCA twice, the noise went away and that appeared odd...could be the Ref 50's close proximity of cables...dunno.
This happened before a long time ago having a loose cable laying around and didn't realize it but no harm. So I measured the DC offset to the amp, I have -.65 on the right and .4 on the left. Also measuring ohms on the speaker terminals of the 2B, I have 3.75 ohms on both speakers with the left tweeter gone and the right tweeter working.
Any thoughts other than the accidental buzz causing a smoked tweeter?
I played them loud a few times, not ear-piercing but kinda loud, no distortion or woofer popping loud and all was fine. Not too long ago my kids were setting up the game console and had the Ref 50 on CD so while searching for sound, they turned it up then changed inputs without turning the sound back down....it was pretty loud and could have compromised something.
Fast forward to yesterday and my left tweeter was out. I had a replacement handy and swapped it out then all was good, the slightly harsh highs were gone. Today I went down to listen to a few CD's and the left tweeter was gone again...
This time nothing was on except for the amp.I did recently acquire a tube preamp which I've been trying a few different tubes which is why I'm doing some A/B testing and swapping back and forth to my Ref 50. The only thing that might be an issue is I turned the amp (B&K 200.2)off before removing IC's then swapped RCA's, when I turned everything back on, I had a buzz from what would appear to be a loose RCA but they were secured into the REF 50, then I quickly turned the amp off again. After I reseated the RCA twice, the noise went away and that appeared odd...could be the Ref 50's close proximity of cables...dunno.
This happened before a long time ago having a loose cable laying around and didn't realize it but no harm. So I measured the DC offset to the amp, I have -.65 on the right and .4 on the left. Also measuring ohms on the speaker terminals of the 2B, I have 3.75 ohms on both speakers with the left tweeter gone and the right tweeter working.
Any thoughts other than the accidental buzz causing a smoked tweeter?
Comments
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I rechecked the DC offset after powering down the amp then back on, waited 30 min and I now have -.2 on the left and -1.1 on the right.
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Update on this, I pulled all the cables, hooked up the left speaker cable to an old loose mid driver, reinstalled the IC's for the left side, nothing else attached to the preamp, powered it all up and it was quiet. I moved the left IC on the rear of the Ref 50 output to amp upwards and the speaker went ballistic with 21 VAC and about 1500HZ based on the DMM.
So the Ref 50 has been moved aside for the VTL 2.5 for now. I may or may not repair the Ref 50 right now, but I will consider a newer used AVR with HDMI for the HT duties as well. -
Man, I was reading this and thinking at first, wow, you've got a working Ref 50; jealous. I picked one up a while back and it was okay for a couple of days, and then started doing some weird stuff. Like you, trying to decide whether to have it repaired.
Sorry to hear of the difficulties. Tragic, the failure of these units, and apparently, not uncommon. They're beautiful and capable, otherwise.
Side note, a Ref 5 S2 sounds pretty nice, if you like the B&K front end, but no DAC.I disabled signatures. -
When I was shopping for a pre/pro, I considered the BK Ref 50. Even when they were still current, there was enough bad publicity about glitches that I went elsewhere.
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Side note, a Ref 5 S2 sounds pretty nice, if you like the B&K front end, but no DAC.
I hear the Series 2 did have improvements as well as added notch filters, i would like to hear them back to back.When I was shopping for a pre/pro, I considered the BK Ref 50. Even when they were still current, there was enough bad publicity about glitches that I went elsewhere.
The Ref 50 does have a few glitches, most complain about the ticking/light pop in changing inputs, but honestly it never bothered me after spending a day with it. The sound quality of the Ref 50 is very good, and the S2 I hear is a slight improvement. I wouldn't hesitate again to buy one if I didn't want to go with tubes or need HDMI.
If you're on a budget and need a great sounding preamp, the Ref50/70 is a fantastic piece. Shame though my RCA jacks took a hit but I could repair it if I had to, but at least I'm not out a ton of $$ at the moment as I only spent $300 on it a couple years ago.....far cry from the original price.
I won't argue there are good used SS pre's that sound as good or better though.
