Major issues with pre and amp
NeilGabriel
Posts: 1,487
I just returned from vacation and switched on my 2 channel amp (NAD C-272) before switching the pre on (B&K Ref 20) (sleep mode). I got a very loud screatching, static constant sound. I pulled the 2 channel outputs from the pre and still got the same sound. When I pulled the inputs to the amp, the noise stopped. It also occurred on the Zone 2 outputs on the pre.
I checked all connections and plugs, etc. Turned the main power off and on. Now, the unit does not make sound unless the interconnects are plugged into the AMP and the Pre...this is a very loud hum even with the volume on the pre turned way down.
No one touched the equipment while I was away. Help please.
[it does appear that there was a power outage while I was again as some clocks needed to be reset and my external drive on the computer was off....I have a very cheap surge protector on the amp...and did try plugging it straight into the wall with no change]
NG
I checked all connections and plugs, etc. Turned the main power off and on. Now, the unit does not make sound unless the interconnects are plugged into the AMP and the Pre...this is a very loud hum even with the volume on the pre turned way down.
No one touched the equipment while I was away. Help please.
[it does appear that there was a power outage while I was again as some clocks needed to be reset and my external drive on the computer was off....I have a very cheap surge protector on the amp...and did try plugging it straight into the wall with no change]
NG
Post edited by NeilGabriel on
Comments
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any storms while you were aeay?Have you checked the fuses?And,,good luck,,let us know what you find.JC approves....he told me so. (F-1 nut)
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apparently there were storms and a brief power outage....I am not sure where to check fuses? under hood? look at amp I would guess....?
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Well, first figure out if it's your pre or the amp, which is fried...Panasonic PT-AE4000U projector for movies
Carada 106" Precision Series (Classic Cinema White)
Denon AVR-X3600H pre/pro
Outlaw 770 7-channel amplifier
B&W CDM1-SE fronts
B&W CDM-CNT center
B&W CDM1 rears on MoPADs
JBL SP8CII in-ceiling height speakers
Samsung DTB-H260F OTA HDTV tuner
DUAL NHT SubTwo subwoofers
Oppo BDP-93 Blu-Ray player
Belkin PF60 Power Center
Harmony 1100 RF remote with RF extender
Sony XBR-X950G 55" 4K HDR Smart TV + PS3 in the living room -
amp....even when not connected to the pre, it makes very loud hum when turned on and with interconnect plugged in....when plugging the interconnect in, it sounds like it wants to blow up....I've experienced this with other gear and the noise goes away once the plug is in...not here....(Sorry, probably sounds too sexual)....
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NeilGabriel wrote: »amp....even when not connected to the pre, it makes very loud hum when turned on and with interconnect plugged in....when plugging the interconnect in, it sounds like it wants to blow up....I've experienced this with other gear and the noise goes away once the plug is in...not here....(Sorry, probably sounds too sexual)....
When you are talking about disappearing hum in case when you attach another piece - you're attaching grounds together, so that's obvious.
If the amp is continuously humming with nothing connected, it's probably fried, so you'll have to get a qualified tech. to look at it.
Panasonic PT-AE4000U projector for movies
Carada 106" Precision Series (Classic Cinema White)
Denon AVR-X3600H pre/pro
Outlaw 770 7-channel amplifier
B&W CDM1-SE fronts
B&W CDM-CNT center
B&W CDM1 rears on MoPADs
JBL SP8CII in-ceiling height speakers
Samsung DTB-H260F OTA HDTV tuner
DUAL NHT SubTwo subwoofers
Oppo BDP-93 Blu-Ray player
Belkin PF60 Power Center
Harmony 1100 RF remote with RF extender
Sony XBR-X950G 55" 4K HDR Smart TV + PS3 in the living room -
big bad smiley face....I really like the amp.....will need to check with NAD about sending it in...
the surprise to me is that I have never lost a piece of equipment. including computer, to any storm event...and the one that must have knocked the amp out could not have been major as my wife barely recalls anything serious....(she was home and I was on vacation).... -
Amplifier issue...do you have a cheap amp handy? Always ALWAYS keeps cheap Goodwill stuff handy to troubleshoot gear.CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
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Agreed, swapping gear with known good units is always the best and easiest way to troubleshoot.Amplifier issue...do you have a cheap amp handy? Always ALWAYS keeps cheap Goodwill stuff handy to troubleshoot gear.
Some was mentioned about checking fuses... When fuses are blowned, you hear NOTHING NO HUMMING or BUZZING. IMHO the problem would more likely be shorted capacitor as other components such as resistors or transistors would either cause the unit to simply not work at all or give you ''smoke signal''. IMHO it shouldn't be too costly to get the unit fixed (unless the repair shop takes advantage of you).
Cheers!
TKDARE TO SOAR:
Your attitude, almost always determine your altitude in life
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pop the hood and look inside.JC approves....he told me so. (F-1 nut)
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Actually I have had this same issue and it WAS a fuse. Pop the hood and look for fuses near the speaker connection.2-channelBelles 22A Pre, Emotiva XPA-2 Gen 2, Marantz SA8005, Pro-Ject RPM-10 Turntable, Pro-Ject Phono Box DS3B, Polk Audio Legend L800's, AudioQuest Cable throughout.
