AudioAficionado.org  

Go Back   AudioAficionado.org > Manufacturers Forums > Vivid Audio

Vivid Audio Auditory Acuity

Reply
 
Thread Tools Display Modes
  #1  
Old 10-15-2015, 09:47 PM
BillK BillK is offline
Senior Member
 
Join Date: Jan 2011
Location: Colorado
Posts: 909
Default Weirdness with Moon Evolution 870A amp overheating on one channel with G2s

Here's a strange one:

Auditioning a Moon Evolution 870A amp with my Giya G2s. It sounded absolutely wonderful, but…

As soon as the amp was powered up, if the right speaker's mid/high cable was attached the amp would start to heat up like crazy. After only about two minutes the amp channel was over 15║F warmer than ambient, and it eventually ended in the amp going into thermal shutdown for that channel after about twenty minutes. I actually burned myself on the amp when it happened the first time, a laser thermometer showing the other channel running at a nice 95║F or so, but the right channel (that shut down) was at 205║F!!

Why I don't understand this is if the cables are connected to any other amp I have handy (Levinson No. 334, Denon POA-8300 or Rotel RB-1552 Mark II) they have absolutely no issues driving the same channel.

Anyone have any ideas as to what's going on or why it doesn't happen with the left channel, or the right channel woofer, just the right mid/high, and why it doesn't occur with other amps?

I even tried connecting the right speaker's cable to the left channel of the amp, and then that channel went into thermal runaway, so it's definitely something about the right channel mid/high that it is having severe issues with.
Reply With Quote
  #2  
Old 10-15-2015, 10:25 PM
jdandy's Avatar
jdandy jdandy is online now
No Work, No Worries



 
Join Date: Apr 2009
Location: North Central Florida
Posts: 51,738
Default

Bill.......Are you running the woofer connected to speaker 1 output and the mid/tweeter to speaker 2 output, or are both the woofer and the mid/tweeter cables connected to speaker 1 output?

Also, are you using unbalanced or balanced interconnects between the preamp and the power amp?
__________________
Dan



STUDIO - McIntosh C1000C/P, MC2301 (2), MR88, Aurender N10, Esoteric K-01X, Sonos Connect, PurePower 2000, Stillpoints, Furutech Flux 50, Michell Gyro SE, Michell HR Power Supply, SME 309, Ortofon Cadenza Black, Wireworld, Sonus faber Amati Anniversario
LIVING ROOM - McIntosh C2300, MC452, MR85, Magnum Dynalab 205, Simaudio MOON Neo 260D-T, Schiit Audio Yggdrasil, Aurender N100H, Micro Seiki DD40, Ortofon Cadenza Blue, Nakamichi BX-300, Sony 60ES DAT, PS Audio P10, Furutech Flux 50, Sonos Connect, Stillpoints, Wireworld, Kimber, PMC EB1i, JL Audio f113
VINTAGE - McIntosh MA230, Tandberg 3011A tuner, Olive 04HD, Sony DTC-59ES DAT, McIntosh 4300V, JBL 4312A

Last edited by jdandy; 10-15-2015 at 11:00 PM.
Reply With Quote
  #3  
Old 10-15-2015, 11:00 PM
BillK BillK is offline
Senior Member
 
Join Date: Jan 2011
Location: Colorado
Posts: 909
Default

Quote:
Originally Posted by jdandy View Post
Bill.......Are you running the woofer connected to speaker 1 output and the mid/tweeter to speaker 2 output, or are both the woofer and the mid/tweeter cables connected to speaker 1 output?
Woofer connected to Speaker 1, High/Mid connected to Speaker 2. Once again weird that it would only have an issue with one channel though. Balanced cables between pre and amp.
Reply With Quote
  #4  
Old 10-15-2015, 11:10 PM
jdandy's Avatar
jdandy jdandy is online now
No Work, No Worries



 
Join Date: Apr 2009
Location: North Central Florida
Posts: 51,738
Default

Bill.......Have you tried swapping the left and right speaker cables to see if the problem follows the cables?
__________________
Dan



STUDIO - McIntosh C1000C/P, MC2301 (2), MR88, Aurender N10, Esoteric K-01X, Sonos Connect, PurePower 2000, Stillpoints, Furutech Flux 50, Michell Gyro SE, Michell HR Power Supply, SME 309, Ortofon Cadenza Black, Wireworld, Sonus faber Amati Anniversario
LIVING ROOM - McIntosh C2300, MC452, MR85, Magnum Dynalab 205, Simaudio MOON Neo 260D-T, Schiit Audio Yggdrasil, Aurender N100H, Micro Seiki DD40, Ortofon Cadenza Blue, Nakamichi BX-300, Sony 60ES DAT, PS Audio P10, Furutech Flux 50, Sonos Connect, Stillpoints, Wireworld, Kimber, PMC EB1i, JL Audio f113
VINTAGE - McIntosh MA230, Tandberg 3011A tuner, Olive 04HD, Sony DTC-59ES DAT, McIntosh 4300V, JBL 4312A
Reply With Quote
  #5  
Old 10-15-2015, 11:29 PM
BillK BillK is offline
Senior Member
 
Join Date: Jan 2011
Location: Colorado
Posts: 909
Default

No, I didn't try swapping cables as my current amps have no issues and, biggest reason, swapping cables is a huge PITA on Vivids. :-)
Reply With Quote
  #6  
Old 10-16-2015, 11:38 AM
jdandy's Avatar
jdandy jdandy is online now
No Work, No Worries



 
Join Date: Apr 2009
Location: North Central Florida
Posts: 51,738
Default

Bill.......I know the G2's have their speaker terminals underneath and it is a two man job to get to them. I doubt seriously there is anything wrong with the speaker wires themselves but perhaps there is something unusual going on at the speaker terminals. I am just going through a process of elimination. It certainly is a peculiar problem.
__________________
Dan



STUDIO - McIntosh C1000C/P, MC2301 (2), MR88, Aurender N10, Esoteric K-01X, Sonos Connect, PurePower 2000, Stillpoints, Furutech Flux 50, Michell Gyro SE, Michell HR Power Supply, SME 309, Ortofon Cadenza Black, Wireworld, Sonus faber Amati Anniversario
LIVING ROOM - McIntosh C2300, MC452, MR85, Magnum Dynalab 205, Simaudio MOON Neo 260D-T, Schiit Audio Yggdrasil, Aurender N100H, Micro Seiki DD40, Ortofon Cadenza Blue, Nakamichi BX-300, Sony 60ES DAT, PS Audio P10, Furutech Flux 50, Sonos Connect, Stillpoints, Wireworld, Kimber, PMC EB1i, JL Audio f113
VINTAGE - McIntosh MA230, Tandberg 3011A tuner, Olive 04HD, Sony DTC-59ES DAT, McIntosh 4300V, JBL 4312A
Reply With Quote
  #7  
Old 10-16-2015, 05:05 PM
BillK BillK is offline
Senior Member
 
Join Date: Jan 2011
Location: Colorado
Posts: 909
Default

That's the thing; were it the speaker or the terminals, I would expect one of the other amps to have an issue with it as well, especially one of the more mass-market amps.

The only thing I can come up with is either the amp is unhappy with capacitance in that particular run of cable, or there's something up with the speaker terminals or speaker that that amp is sensitive to and that cheaper amps work around (e.g. If this amp is direct coupled and the others have bypass caps.)
Reply With Quote
  #8  
Old 10-16-2015, 07:32 PM
jdandy's Avatar
jdandy jdandy is online now
No Work, No Worries



 
Join Date: Apr 2009
Location: North Central Florida
Posts: 51,738
Default

Quote:
Originally Posted by BillK View Post
That's the thing; were it the speaker or the terminals, I would expect one of the other amps to have an issue with it as well, especially one of the more mass-market amps.

The only thing I can come up with is either the amp is unhappy with capacitance in that particular run of cable, or there's something up with the speaker terminals or speaker that that amp is sensitive to and that cheaper amps work around (e.g. If this amp is direct coupled and the others have bypass caps.)
Bill.......What's unusual is the problem follows the speaker when you shift the wires to the opposite channel of the amplifier so it seems as though the amplifier is fine. It's a head scratcher.
__________________
Dan



STUDIO - McIntosh C1000C/P, MC2301 (2), MR88, Aurender N10, Esoteric K-01X, Sonos Connect, PurePower 2000, Stillpoints, Furutech Flux 50, Michell Gyro SE, Michell HR Power Supply, SME 309, Ortofon Cadenza Black, Wireworld, Sonus faber Amati Anniversario
LIVING ROOM - McIntosh C2300, MC452, MR85, Magnum Dynalab 205, Simaudio MOON Neo 260D-T, Schiit Audio Yggdrasil, Aurender N100H, Micro Seiki DD40, Ortofon Cadenza Blue, Nakamichi BX-300, Sony 60ES DAT, PS Audio P10, Furutech Flux 50, Sonos Connect, Stillpoints, Wireworld, Kimber, PMC EB1i, JL Audio f113
VINTAGE - McIntosh MA230, Tandberg 3011A tuner, Olive 04HD, Sony DTC-59ES DAT, McIntosh 4300V, JBL 4312A
Reply With Quote
  #9  
Old 10-21-2015, 08:17 PM
Art Vandelay's Avatar
Art Vandelay Art Vandelay is offline
Senior Member
 
Join Date: May 2015
Location: Sydney, Australia
Posts: 300
Default

Quote:
Originally Posted by jdandy View Post
Bill.......What's unusual is the problem follows the speaker when you shift the wires to the opposite channel of the amplifier so it seems as though the amplifier is fine. It's a head scratcher.
Does the problem occur without playing music?

If the answer is yes then the amplifier is most likely breaking into HF oscillation.

And if that's the case it's possible that the combination of speaker cable and speaker's impedance is the cause. Is the problem speaker connected by a longer cable?
Reply With Quote
  #10  
Old 10-21-2015, 08:56 PM
BillK BillK is offline
Senior Member
 
Join Date: Jan 2011
Location: Colorado
Posts: 909
Default

Nope, music needs to be playing.

Both cables (all four actually) are the same length.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Audioaficionado.org tested by Norton Internet Security

All times are GMT -4. The time now is 12:25 PM.



Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
ęCopyright 2009-2018 AudioAficionado.org.Privately owned, All Rights Reserved.
Audio Aficionado Sponsors
AudioAficionado Subscriber
AudioAficionado Subscriber
Fortress
Fortress
Harmonic Resolution Systems
Harmonic Resolution Systems
Wyred4Sound
Wyred4Sound
Dragonfire Acoustics
Dragonfire Acoustics
GIK Acoustics
GIK Acoustics
Esoteric
Esoteric
AC Infinity
AC Infinity
JL Audio
JL Audio
Acoustic Sciences Corportation
Acoustic Sciences Corportation
Legend Audio & Video
Legend Audio & Video
Audio by E
Audio by E
Canton
Canton
Bryston
Bryston
WireWorld Cables
WireWorld Cables
Stillpoints
Stillpoints
Bricasti Design
Bricasti Design
Furutech
Furutech
Shunyata Research
Shunyata Research
Accuphase
Accuphase