New Posts New Posts RSS Feed - Stumped! Something in my system overloads amps
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Welcome to the Graham Slee Audio Products Owners Forum

 

Open to all owners plus those contemplating the purchase of a Graham Slee HiFi System Components audio product and wishing to use this forum's loaner program: join here (Rules on posting can be found here)

This website along with trade marks Graham Slee and HiFi System Components are owned by Cadman Enterprises Ltd


Stumped! Something in my system overloads amps

 Post Reply Post Reply Page  12>
Author
lfc jon View Drop Down
Senior Member
Senior Member
Avatar

Joined: 23 Jan 2018
Location: Devon
Status: Offline
Points: 3972
Post Options Post Options   Thanks (0) Thanks(0)   Quote lfc jon Quote  Post ReplyReply Direct Link To This Post Topic: Stumped! Something in my system overloads amps
    Posted: 21 Sep 2021 at 7:29pm
A bit costly but you got there in the end. Happy listening.
Reflex M, Solo (both with PSU-1) CuSat50, Lautus, Spatia & Spatia links cables. Ortofon Bronze.
Back to Top
Fatmangolf View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 23 Dec 2009
Location: Middlesbrough
Status: Offline
Points: 8958
Post Options Post Options   Thanks (0) Thanks(0)   Quote Fatmangolf Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 7:01pm
It is good to know you've got to the bottom of it.

Jon

Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC.
Back to Top
discrete badger View Drop Down
Senior Member
Senior Member
Avatar

Joined: 14 Jul 2009
Status: Offline
Points: 479
Post Options Post Options   Thanks (1) Thanks(1)   Quote discrete badger Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 2:00pm
Yes, speakers - and their connections - absolutely can ruin an amp. I have a dead Cyrus One in the attic as evidence of what happens when the folly of youth thinks it's a good idea to connect up the speakers with the amp on, accidentally shorting out the speaker leads in the process. (Spoiler alert: it's not a good idea)

There are even some amplifiers (certainly not the ones that Graham makes!) which can be damaged if the speaker connection is lost - not even shorted out - whilst playing a signal. Then you get some amp designs which can become unstable with high capacitance on the selected speaker cables, damaging the amp and/or the tweeters.

There are also some speaker designs (I am thinking of Electrostats here, notably the Quad ESL63 and later iterations) whose overdriving protection circuit places a low-impedance crowbar across the speaker terminals. I think this is supposed to send the amp into protection and/or blow its fuses. You can guess what happens when the amp doesn't have either. But when you consider the hassle of transport and costs of repairing the amp, versus those of the speaker, the crowbar idea makes quite a lot of sense.


Back to Top
Graham Slee View Drop Down
Admin Group
Admin Group
Avatar
Retired

Joined: 11 Jan 2008
Location: South Yorkshire
Status: Offline
Points: 16298
Post Options Post Options   Thanks (0) Thanks(0)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 8:16am
It was just something that sprang to mind, and after I'd read an article about it, saying that frequencies up to 20Hz might be so resonant that they could be several dB's up compared to the signal amplitude.

I thought that if you'd set the volume pretty high to start with, that the lows we can't hear, could be so much larger in amplitude, that they might trigger the protection circuit on your amp. 

Protection circuits have low pass filter capacitors to ignore normal signal, but at such low frequencies they would start to turn on and cut power, whichever way they're configured.

After looking at the cartridge and arm specs, I thought there could be a bit more of a mismatch than you had with the 1042 - because that looked problematic too. And that's why I suggested trying to up the mass, but you've already been there.
That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
Back to Top
Pushpaw View Drop Down
Senior Member
Senior Member


Joined: 25 Jul 2020
Location: Canada
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote Pushpaw Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 2:55am
Funnily enough, I dealt with that issue a long time ago and indeed used blue tak to add mass. I also use weighted mounting screws. I probably added about 8-10 grams all said and done. I also had to add a significant amount of blue tak to counterweight to balance it out, and also put small stainless steel nuts in the blue tak for more weight. And yes I use a tracking force gauge to make sure it’s set right as the dial on the tonearm is completely inaccurate with the added weight. Good thing to mention as I would not recommend the Goldring 2500 (or 1042) with Debut Carbon without adding mass to the arm somehow. 


P******t Debut Carbon, Goldring 1042, GS Accession MM w/Enigma, GS Solo ULDE w/PSU1, Sennheiser HD6XX, Technics SU-800 IA, Castle Knight 1, PS Audio Ultimate Outlet, Lautus & CuSat50
Back to Top
Pushpaw View Drop Down
Senior Member
Senior Member


Joined: 25 Jul 2020
Location: Canada
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote Pushpaw Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 2:45am
Originally posted by Fatmangolf Fatmangolf wrote:

Which input on the amp are you using, please?

There’s only one input that I’m aware of on the Zamp v3. At least only one rca input. There’s a 12 V input too I think but I’m not even sure what it’s for. 
P******t Debut Carbon, Goldring 1042, GS Accession MM w/Enigma, GS Solo ULDE w/PSU1, Sennheiser HD6XX, Technics SU-800 IA, Castle Knight 1, PS Audio Ultimate Outlet, Lautus & CuSat50
Back to Top
Pushpaw View Drop Down
Senior Member
Senior Member


Joined: 25 Jul 2020
Location: Canada
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote Pushpaw Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep 2021 at 1:05am
thanks all for your responses. Did some fiddling today and resolved the issue. 

Great diagnostic advice badger. I first searched for possible sources of sub sonic bass and I figured the motor would likely have presented itself when the old cartridge was on. The new cartridge seemed to be the catalyst. So I wondered if there was a poor connection in one of the wires from cart to TT. In fact, one of the wires for left channel previously broke from the solder so I have trouble with that connection. I carefully undid each connector pin and redid them all and even stripped the wire of the unsoldered one to give more bare wire for a connection. 

Result was that there was no effect! The darn thing was still running in protect mode at modest volumes. 

So I retrieved the necessary connectors and plugged in the laptop and played YouTube. Guess what? Still overloading! Conclusion: it wasn’t the turntable setup.

So I got my second pair of speakers from basement (Mission model 70) and hooked them up. And everything worked perfectly. Amp didn’t play in protect mode. 

I was confused but relieved. Apparently my speakers blew my two Technics amps. Huh??? How and what’s connection to change in cartridge?

I have a theory. I think that when I changed cartridge I moved some of my equipment. Don’t remember why exactly. Just fiddling with ground wire on the Accession etc and that sort of behind/beside my speaker. I also think I swapped lautus and CuSat for fun.

I think that in doing so a few filaments of speaker wire from the right speaker ended up in contact with the wrong speaker node. So it was overloading because the right speaker was connected improperly. And that’s what blew my two amps and sent current Parasound Zamp into protect mode. Supporting this theory is that the Zamp would have a green light on left channel and the right channel light would go out when overloading. 

At first I thought my castle speakers were somehow ruined and I was stuck with the Mission speakers. They are ok but it’s a noticeable downgrade in sound quality. 

Anyway, turns out I just had to reconnect the castle speakers and be careful to keep stray filaments away from the wrong mode. 

System works great now. 

End of story. 

I learned a valuable lesson. One is an overload circuit is a great feature to have. Another is that speakers can ruin amps - something I didn’t know previously. 

And by the way, might as well add that the Accession and Goldring 2500 are a phenomenal combination. Sound incredible. I’m in audio heaven lately. Only headphones for a while there but looking forward to more speaker listening too, now that I have a working amp. And the Accession is working great as a preamp feeding into the modest power amp. 


Edited by Pushpaw - 21 Sep 2021 at 1:12am
P******t Debut Carbon, Goldring 1042, GS Accession MM w/Enigma, GS Solo ULDE w/PSU1, Sennheiser HD6XX, Technics SU-800 IA, Castle Knight 1, PS Audio Ultimate Outlet, Lautus & CuSat50
Back to Top
 Post Reply Post Reply Page  12>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.125 seconds.