Chasing an Elusive Hum
Moderator: James Steele
Forum rules
Here's where to talk about preamps, cables, microphones, monitors, etc.
Here's where to talk about preamps, cables, microphones, monitors, etc.
- Rick Cornish
- Posts: 1135
- Joined: Sun Feb 17, 2013 9:07 pm
- Primary DAW OS: MacOS
- Location: Ely, MN USA
- Contact:
Re: Chasing an Elusive Hum
Thanks, Mike O. I'm leaning towards finding a used audiophile-oriented amp. Bryston (as you suggested), Anthem, etc. 150w+ per channel into 4 ohms. Hello, eBay.
Rick Cornish
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
Re: Chasing an Elusive Hum
It bothers me that your RA-150 checked out fine at Alesis. I can't imagine they would knowingly send it back to you with a problem. Maybe it IS fine. I think the suggestion of taking it to your cousin's house was a good one. Perhaps there is a power line problem at your location and the Alesis amp is just more susceptible to it. Find out for sure if there's a problem with it before buying a new one. Just thinkin' out loud here.
Phil
Phil
DP 11.23, 2020 M1 Mac Mini [9,1] (16 Gig RAM), Mac Pro 3GHz 8 core [6,1] (16 Gig RAM), OS 14.3.1/11.6.2, Lynx Aurora (n) 8tb, MOTU 8pre-es, MOTU M6, MOTU 828, Apogee Rosetta 800, UAD-2 Satellite, a truckload of outboard gear and plug-ins, and a partridge in a pear tree.
- mikehalloran
- Posts: 15374
- Joined: Sun Jan 25, 2009 5:08 pm
- Primary DAW OS: MacOS
- Location: Sillie Con Valley
Re: Chasing an Elusive Hum
I agree with Phil that you still want to eliminate the line as your source of noise.
Something to watch for is an old Lexicon NT 212. It's the Bryson 3Bst (120W @ 8 / 200W @ 4 Ohms). The Lexicon 225 is the Bryston 4Bst (250 @ 8 / 400W @ 4 Ohms).
The other Lexington NT/Bryston amps were the 312 (5Bst) and 412 (8Bst) 3 and 4 channel versions of the 212/3Bst The NT 501 is an 800W mono amp but I forget the Bryston model.
http://pdfstream.manualsonline.com/8/85 ... 7cd5dd.pdf
Something to watch for is an old Lexicon NT 212. It's the Bryson 3Bst (120W @ 8 / 200W @ 4 Ohms). The Lexicon 225 is the Bryston 4Bst (250 @ 8 / 400W @ 4 Ohms).
The other Lexington NT/Bryston amps were the 312 (5Bst) and 412 (8Bst) 3 and 4 channel versions of the 212/3Bst The NT 501 is an 800W mono amp but I forget the Bryston model.
http://pdfstream.manualsonline.com/8/85 ... 7cd5dd.pdf
DP 11.31; 828mkII FW, micro lite, M4, MTP/AV USB Firmware 2.0.1
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
- guitardood
- Posts: 144
- Joined: Sun Nov 19, 2006 3:55 am
- Primary DAW OS: MacOS
Re: Chasing an Elusive Hum
I was going to suggest this as well. FWIW, my Yamaha S-80 keyboard had a bad hum problem and I tried everything, until finally, just for shits and giggles, I modded a power cord (atypical NEMA 5-15P to C13) and reversed the blade wires. Hum disappeared. None of my other gear had a problem and the outlets were definitely wired correctly. Something to try.Phil O wrote:Perhaps there is a power line problem at your location and the Alesis amp is just more susceptible to it. Find out for sure if there's a problem with it before buying a new one. Just thinkin' out loud here.
Phil
________________________________________________________________________
Best,
Guitardood
Chuck Fletcher on Reverb Nation
Chuck Fletcher on Facebook
"Life is like a box of chocolates. You know, eventually you're going to get the one filled with alien-like nasty tasting goo and have to spit it out and say YUCK".
Best,
Guitardood
Chuck Fletcher on Reverb Nation
Chuck Fletcher on Facebook
"Life is like a box of chocolates. You know, eventually you're going to get the one filled with alien-like nasty tasting goo and have to spit it out and say YUCK".
- Rick Cornish
- Posts: 1135
- Joined: Sun Feb 17, 2013 9:07 pm
- Primary DAW OS: MacOS
- Location: Ely, MN USA
- Contact:
Re: Chasing an Elusive Hum
Thanks, Phil and Guitardood. I agree with HCMarcus's test suggestion. Unfortunately, I'm in a very remote area......no "cousins" nearby. I'll find some other way to test it this week.
Called a hifi shop I know down in the Twin Cities and found a used Acurus A 250 for $500, which could be interesting. Would rather have a Bryston, Anthem, Carver or Hafler, if I could find the right one in my price range.
Called a hifi shop I know down in the Twin Cities and found a used Acurus A 250 for $500, which could be interesting. Would rather have a Bryston, Anthem, Carver or Hafler, if I could find the right one in my price range.
Rick Cornish
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
- HCMarkus
- Posts: 9812
- Joined: Tue Jan 10, 2006 9:01 am
- Primary DAW OS: MacOS
- Location: Rancho Bohemia, California
- Contact:
Re: Chasing an Elusive Hum
Yamaha keyboards connected via USB exhibit ground loop issues, such as you experienced. I have solved that problem by modifying a USB cable - cut the USB ground wire.guitardood wrote:FWIW, my Yamaha S-80 keyboard had a bad hum problem and I tried everything, until finally, just for shits and giggles, I modded a power cord (atypical NEMA 5-15P to C13) and reversed the blade wires. Hum disappeared. None of my other gear had a problem and the outlets were definitely wired correctly. Something to try.
Modifying a polarized plug to allow reversal can be very dangerous. That ON OFF switch still turns off the device, but the device is still hot and hazardous, with 120 volt waiting to bite the unsuspecting. Reversal of polarity is way more dangerous than removing or lifting the ground (plug third prong).
- guitardood
- Posts: 144
- Joined: Sun Nov 19, 2006 3:55 am
- Primary DAW OS: MacOS
Re: Chasing an Elusive Hum
Wasn't connected via USB, just MIDI & audio. Ground lifts didn't work, only think that got rid of the hum was reverse polarity. I've got a friend with a Yamaha Motif with exactly same issue and same solution. The Motif Rack uses a wall-wart and doesn't have the problem. Haven't got shocked or fried anything yet (knocking on every piece of faux wood in my vicinity, LOL!)HCMarkus wrote:Yamaha keyboards connected via USB exhibit ground loop issues, such as you experienced. I have solved that problem by modifying a USB cable - cut the USB ground wire.guitardood wrote:FWIW, my Yamaha S-80 keyboard had a bad hum problem and I tried everything, until finally, just for shits and giggles, I modded a power cord (atypical NEMA 5-15P to C13) and reversed the blade wires. Hum disappeared. None of my other gear had a problem and the outlets were definitely wired correctly. Something to try.
Modifying a polarized plug to allow reversal can be very dangerous. That ON OFF switch still turns off the device, but the device is still hot and hazardous, with 120 volt waiting to bite the unsuspecting. Reversal of polarity is way more dangerous than removing or lifting the ground (plug third prong).
________________________________________________________________________
Best,
Guitardood
Chuck Fletcher on Reverb Nation
Chuck Fletcher on Facebook
"Life is like a box of chocolates. You know, eventually you're going to get the one filled with alien-like nasty tasting goo and have to spit it out and say YUCK".
Best,
Guitardood
Chuck Fletcher on Reverb Nation
Chuck Fletcher on Facebook
"Life is like a box of chocolates. You know, eventually you're going to get the one filled with alien-like nasty tasting goo and have to spit it out and say YUCK".
- mikehalloran
- Posts: 15374
- Joined: Sun Jan 25, 2009 5:08 pm
- Primary DAW OS: MacOS
- Location: Sillie Con Valley
Re: Chasing an Elusive Hum
My house is 2-wire, no ground. I've reversed polarity a few times to reduce hum. That opens a real can of worms when dealing with a power amp -- if that fixes it, I'd replace the amp.
That said, high end amplifiers are generally very good at diminishing noise that plagues lesser quality products.
In my case, I'd try to ascertain if line noise is the problem or if the amp is the problem. I still think a better amp is the solution based on a thorough description of the problem. I could be wrong...
That said, high end amplifiers are generally very good at diminishing noise that plagues lesser quality products.
In my case, I'd try to ascertain if line noise is the problem or if the amp is the problem. I still think a better amp is the solution based on a thorough description of the problem. I could be wrong...
DP 11.31; 828mkII FW, micro lite, M4, MTP/AV USB Firmware 2.0.1
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
- Rick Cornish
- Posts: 1135
- Joined: Sun Feb 17, 2013 9:07 pm
- Primary DAW OS: MacOS
- Location: Ely, MN USA
- Contact:
Re: Chasing an Elusive Hum
I'm inclined to agree. I knew I was taking a risk with the Alesis....they're not known for building high-end gear, but the published specs met my needs and the price was right.mikehalloran wrote:I still think a better amp is the solution based on a thorough description of the problem. I could be wrong...
I thought I'd crossed amp issues off the list when I sent it in. Subject to verification, I am inclined to say this is the problem. If so, either the Alesis tech missed the issue or their own spec is such that the hum I'm getting is considered to be within tolerance. I'll pull the amp this afternoon and plug one channel of my home theater speakers into in tonight. That should prove something.
Rick Cornish
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
- monkey man
- Posts: 13955
- Joined: Fri Apr 22, 2005 10:01 pm
- Primary DAW OS: MacOS
- Location: Melbourne, Australia
Re: Chasing an Elusive Hum
Sorry I'm so late to the "party", Rick.EMRR wrote:The earliest Alesis power amps all had some obvious residual hum, I haven't heard that model.
I ran an RA100 for several years into Alesis Monitor Ones via Monster cables and had the same issue.
Obvious question based upon my experience with the lower-powered model:
Does the hum stop when you touch the amp's chassis? Have you tried this?
Mac 2012 12C Cheese Grater, OSX 10.13.6
MOTU DP8.07, MachFive 3.2.1, MIDI Express XT, 24I/O
Novation, Yamaha & Roland Synths, Guitar & Bass, Kemper Rack
Pretend I've placed your favourite quote here
Re: Chasing an Elusive Hum
Hmm. I've had an RA100 for many years. It currently powers the speakers connected to my TV. Quiet as a monkey...err mouse. It's been a great amp. No noticeable hum.
Phil
Phil
DP 11.23, 2020 M1 Mac Mini [9,1] (16 Gig RAM), Mac Pro 3GHz 8 core [6,1] (16 Gig RAM), OS 14.3.1/11.6.2, Lynx Aurora (n) 8tb, MOTU 8pre-es, MOTU M6, MOTU 828, Apogee Rosetta 800, UAD-2 Satellite, a truckload of outboard gear and plug-ins, and a partridge in a pear tree.
- monkey man
- Posts: 13955
- Joined: Fri Apr 22, 2005 10:01 pm
- Primary DAW OS: MacOS
- Location: Melbourne, Australia
Re: Chasing an Elusive Hum
Maybe you got lucky, Phil?
We had a character called Lucky Phil in drink-driving ads here in Jungleville for some years.
Here he is:
https://www.youtube.com/watch?v=aoy7ChrynNw
Note that the policeman sounds like Crocodile Dundee. LOL
We had a character called Lucky Phil in drink-driving ads here in Jungleville for some years.
Here he is:
https://www.youtube.com/watch?v=aoy7ChrynNw
Note that the policeman sounds like Crocodile Dundee. LOL
Mac 2012 12C Cheese Grater, OSX 10.13.6
MOTU DP8.07, MachFive 3.2.1, MIDI Express XT, 24I/O
Novation, Yamaha & Roland Synths, Guitar & Bass, Kemper Rack
Pretend I've placed your favourite quote here
Re: Chasing an Elusive Hum
Could be. Or maybe you got unlucky. Dunno. But, I make it a point to never drive while I'm drinking. The driving part is too distracting.
Phil
Phil
DP 11.23, 2020 M1 Mac Mini [9,1] (16 Gig RAM), Mac Pro 3GHz 8 core [6,1] (16 Gig RAM), OS 14.3.1/11.6.2, Lynx Aurora (n) 8tb, MOTU 8pre-es, MOTU M6, MOTU 828, Apogee Rosetta 800, UAD-2 Satellite, a truckload of outboard gear and plug-ins, and a partridge in a pear tree.
- Rick Cornish
- Posts: 1135
- Joined: Sun Feb 17, 2013 9:07 pm
- Primary DAW OS: MacOS
- Location: Ely, MN USA
- Contact:
Re: Chasing an Elusive Hum
Amp tested outside my studio this morning: Plugged the center channel speaker from my home theater into one channel with no input and the pots all the way down: Same hum present. So the Alesis is guilty as charged and I'm officially shopping for a new amp. Given that the Westlakes are rated at IEC 80W short/200W long and 4 ohms nominal (2 ohms minimum), this is becoming a challenge.
http://www.westlakeaudio.com/Speakers/P ... bbsm4.html
The hifi stuff I've looked at isn't rated below 8 ohms and many don't have balanced inputs. Bruce Swedien drives his with Electrocompaniet monoblocks (which run $4800 a piece). That's about 10x my budget. So, the search continues....
http://www.westlakeaudio.com/Speakers/P ... bbsm4.html
The hifi stuff I've looked at isn't rated below 8 ohms and many don't have balanced inputs. Bruce Swedien drives his with Electrocompaniet monoblocks (which run $4800 a piece). That's about 10x my budget. So, the search continues....
Rick Cornish
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
DP 11 on M2 Mac Studio (64mB mem. + 2tB int. SSD + two 2tB ext. SSDs, and Mac OS Sonoma). VIs from MOTU, Spectrasonics, NI, UVI, 8dio, Soniccouture, East West, Spitfire, Heavyocity, Vir2, and more; plus Waves 14, Brainworx, iZotope, Wavesfactory, Oeksound, Final Mix, JST, SPL, PSP, UVI, Valhalla DSP, and other FX plugs, Roland A-88, Apogee Quartet, iCON Platform Nano, Genelec 1032a and Westlake BBSM4 monitors, Gibson HR Fusion III. rickcornish.net
- mikehalloran
- Posts: 15374
- Joined: Sun Jan 25, 2009 5:08 pm
- Primary DAW OS: MacOS
- Location: Sillie Con Valley
Re: Chasing an Elusive Hum
http://www.ebay.com/itm/Bryston-Limited ... 2354cdfc18
See if he'll take a grand.
http://www.ebay.com/sch/i.html?_odkw=br ... 2&_sacat=0
3 channel version of the same amp might not get bids if no one understands what it is. You can use two channels.
See if he'll take a grand.
http://www.ebay.com/sch/i.html?_odkw=br ... 2&_sacat=0
3 channel version of the same amp might not get bids if no one understands what it is. You can use two channels.
DP 11.31; 828mkII FW, micro lite, M4, MTP/AV USB Firmware 2.0.1
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro
2023 Mac Studio M2 8TB, 192GB RAM, OS Sonoma 14.5 b4, USB4 8TB external, M-Audio AIR 192|14, Mackie ProFxv3 6/10/12; 2012 MBPs Catalina, Mojave
IK-NI-Izotope-PSP-Garritan-Antares, LogicPro X, Finale 27.4, Dorico 5.2, Notion 6, Overture 5, TwistedWave, DSP-Q 5, SmartScore64 Pro, Toast 20 Pro