Gryphon Amplifier Crackle? Help!

[LL21]

Thanks, Microstrip and Nature,

Even if removing the adaptors permanently does not fix the occasional loud buzz i get from time to time...being able to eliminate the soft transformer hum is a pure audio improvement...plus it might actually eliminate the cause of whatever is triggering the Gryphon to buzz loudly once every few hours.

 

[Orb]

Thanks, Microstrip and Nature,

Even if removing the adaptors permanently does not fix the occasional loud buzz i get from time to time...being able to eliminate the soft transformer hum is a pure audio improvement...plus it might actually eliminate the cause of whatever is triggering the Gryphon to buzz loudly once every few hours.

Although you had the buzz when using an XLR preamp didnt you?
Asking as I may had misunderstood the results and setup when using the temporary preamp, why I suggested even though Gryphon has had the amp back once, this info would be very useful to their support engineer and puts more onus on them to fix it.
I find the support engineer usually is one of those involved building that respective product, going by other audio companies of a similar size anyway.

Thanks
Well at a minimum no hum anyway so thats good from all of this

Cheers
Orb

 

[LL21]

Hi Orb,

yes...the mystery loud buzz which comes once (in only one channel) every few hours for just 10-60 seconds...has come under every conceivable iteration of equipment, cabling, system (and isolated with nothing connected to it) that we could come up with. it is either something in my system which is silently destabilizing my unit (and therefore nearly impossible to chase)...or the Amp is just going to reveal a tiny resistor/capacitor someday that has been the culprit all along.

But again, if using my manufacturing friend's new cable with Xhadow XLR connectors, i can get rid of XLR adaptors and also get rid of the transformer hum entirely, that is just a pure audio benefit i am happy to have...plus it actually is a superior cable in terms of decay, detail retrieval, and 'composure' under complex musical passages...every remains in synch but also easily separated so you can listen to any area within the complex musical passage. Who wouldn't want that?

 

[LL21]

Try a different DAC and see if the problem goes away. You have far more patience than I do. I would have thrown that amp out the window a long time ago.

Oh - i forgot to add, that i used the signal outs on my little oppo and removed the DAC entirely...still got the buzz after playing a bunch of movies.

 

[fas42]

Yep, it's falling into place: you're going to have to ditch the old Transparent REf SE cables. The combination of the Gryphon, old cable and XLR is triggering an instability in the amp, it's actually oscillating and if you looked at it on a 'scope it would look very nasty indeed. Cables ain't cables (another Aussie ref.) !!! That's why even touching affects the misbehaviour at times: there's nothing intrinsically wrong with the amp, it's just trying to deal with an invisible, nasty feedback loop which gives it a form of Parkinson's disease ...

This ain't negative feedback, this is positive feedback so to speak, which is a hell of a lot worse!

Frank

 

[LL21]

Thanks, Frank. I am going to google it...i have heard of oscillating. What is it (in layman's terms?)

 

[LL21]

Ok...my layman's interpretation of oscillation as a diagnosis:

1. i picked exactly the wrong combination of pre, cable, adaptor and amp

2. my symptoms below are potentially consistent with oscillation:
- one channel only ever at one time...though it flipped from L only to R only after several months
- tends to happen after 12+ hours intensive use at high volume (movie soundtracks)...when it would buzz every few seconds (vs every few hours)
- no one else could replicate the problem in their own testing benches
- after 15 hours intense use & ridiculous buzzing, i still got buzz next morning immediately on switch on...but if used gently, it would lessen
- and if i left unit unplugged for 2 days...it would be gone when switched back on...until several days of use.

3. PLUS, using my old Transp Ref SE cables (even with new preamp and new XLR termination on one end)...i still hear transformer hum coming thru both speakers...it is very quiet...but always there. i can hear it standing 3-5 feet from speakers with music off and room quiet.

By contrast, using my friends new SE cables (and using Neutrik XLR adaptors)...the speakers are so quiet, with my ear touching the tweeter foam, i hear absolutely nothing. silent...i cannot tell if my system is turned on or off, even this close to the speakers. and i have both tube DAC and pre in my system

HYPOTHESIS: This could indicate some sort of random 'positive loop' of feedback that is feeding back into the amp...causing oscillation???


Does this seem like a plausible hypothesis at this time?

4. I am still using my Transp Ref cables because they have been reterminated with Xhadow XLRs, and i am concerned the Neutrik adaptors were not good. i have also switched preamps at this stage.

i also have asked my friend who manufacturers the SE cable which gave NO transformer hum whatsoever, to take my new Xhadow XLRs off my Transp Ref cables and put them on a new pair of his SE cables, and i will buy it from him.

5. Does this seem a sensible way forward to the pros here?

Thank you!!!!!

 

[fas42]

By contrast, using my friends new SE cables (and using Neutrik XLR adaptors)...the speakers are so quiet, with my ear touching the tweeter foam, i hear absolutely nothing. silent...i cannot tell if my system is turned on or off, even this close to the speakers. and i have both tube DAC and pre in my system

HYPOTHESIS: This could indicate some sort of random 'positive loop' of feedback that is feeding back into the amp...causing oscillation???


Does this seem like a plausible hypothesis at this time?

4. I am still using my Transp Ref cables because they have been reterminated with Xhadow XLRs, and i am concerned the Neutrik adaptors were not good. i have also switched preamps at this stage.

i also have asked my friend who manufacturers the SE cable which gave NO transformer hum whatsoever, to take my new Xhadow XLRs off my Transp Ref cables and put them on a new pair of his SE cables, and i will buy it from him.

5. Does this seem a sensible way forward to the pros here?

Thank you!!!!!

I waited for someone else to add any thoughts, but they haven't, so your last point seems a good way forward. I would just suggest that as soon as you get them back that you confirm, with your head against the tweeter, that this final arrangement is as quiet as you experienced with the Neutriks, otherwise it could have all been in vain !!

In this game, it's all about combinations ...

Frank

 

[LL21]

I waited for someone else to add any thoughts, but they haven't, so your last point seems a good way forward. I would just suggest that as soon as you get them back that you confirm, with your head against the tweeter, that this final arrangement is as quiet as you experienced with the Neutriks, otherwise it could have all been in vain !!

In this game, it's all about combinations ...

Frank

Thanks, Frank. appreciate your continued help. The manufacturer is on holiday, but has been kindly emailing back and forth. He said he would look after this when he returned...so maybe 3 weeks or so. meanwhile, i am using the TA Ref with Xhadow XLR. I will say, the Gryphon was much less hot than normal, even after watching 2 hour movie and listening to 12 hours of music. No loud buzz yesterday, though it is occassional now. We'll see... Thanks again!

 

[LL21]

Well...this puppy is on its way back under Warranty. I think at the end of the day, the simplest solution is probably the right one...it is a little solder, transistor, capacitor buried somewhere inside...and someone will have to take the time to find it.

Meawhile, I have a chance to hear Krell FPB650 monos in next week or 2...10 years old like my Antileon...but certainly a formidable reputation in its day. Interestingly, i read that D'Agostino designed these for the X-1/Grand Slamms and Grand Utopias back when he owned the Slamms in 1998-2000. Since i run the older X-1/Grand Slamms, any thoughts on whether Antileon is a lateral move or upgrade to FPB650monos? i have heard the 750mc monos are much bette stillr...sometimes that is true, and other times not so much. (BTW, i admit to liking the Antileon because it is smooth, superbly powerful...and a touch dark. i have heard the older FPB Class A amps are similar (at least in comparison to newer Evo series amps).

Fingers crossed on Gryphon repair which is the first order of business. But on fpb650 monos running my X-1/Grand Slamms...advice is welcome! (front end is zanden digital and CJ tube pre). thanks!

 

[naturephoto1]

Well...this puppy is on its way back under Warranty. I think at the end of the day, the simplest solution is probably the right one...it is a little solder, transistor, capacitor buried somewhere inside...and someone will have to take the time to find it.

Meawhile, I have a chance to hear Krell FPB650 monos in next week or 2...10 years old like my Antileon...but certainly a formidable reputation in its day. Interestingly, i read that D'Agostino designed these for the X-1/Grand Slamms and Grand Utopias back when he owned the Slamms in 1998-2000. Since i run the older X-1/Grand Slamms, any thoughts on whether Antileon is a lateral move or upgrade to FPB650monos? i have heard the 750mc monos are much bette stillr...sometimes that is true, and other times not so much. (BTW, i admit to liking the Antileon because it is smooth, superbly powerful...and a touch dark. i have heard the older FPB Class A amps are similar (at least in comparison to newer Evo series amps).

Fingers crossed on Gryphon repair which is the first order of business. But on fpb650 monos running my X-1/Grand Slamms...advice is welcome! (front end is zanden digital and CJ tube pre). thanks!

Hi Lloyd,

As I recall, Krell offered a service and could modify the Krell 650 FPB monoblocks turning them into the Krell 750 MC monoblocks. But, I am not sure if this service is still being offered. I would not be surprised if they will, but I have no idea of the cost of said modification.

Rich

 

[LL21]

Rich,

That is interesting! i did not know that...thanks. i have heard good things about the 750monos...i am just a little surprised. The 650 monos are actually quite small...each mono put together would be the size of one Gryphon Antileon...and 1 750mc (at least from the way the pictures portray the 750)...i could be wrong. i will find out.

 

[LL21]

Hi Rich, i checked with Krell...no upgrades available for 650monos. I have been advised to be careful given the age in any event, and further that (assuming the Gryphon will finally work consistently!) it is a superior amp in any event.

 

[naturephoto1]

Hi Rich, i checked with Krell...no upgrades available for 650monos. I have been advised to be careful given the age in any event, and further that (assuming the Gryphon will finally work consistently!) it is a superior amp in any event.

Hi Lloyd,

OK on that. I did confirm on-line about the question and there are some listings about doing the upgrade from the Krell FPB 650MC to the Krell 750 FPB MCX, but that was back in about 2003 or 2004. So, that is quite some time ago at this point. Sorry the service is no longer offered. It is interesting though, that Krell will service all of their amps and keep them in fine order that have been in production so much earlier in time but express such reservation about the units.

Good luck in getting the Gryphon situation resolved or finding a suitable substitute.

Rich

 

[LL21]

Thanks, Rich. will update when the Gryphon is diagnosed.

 

[mep]

I swear I would have thrown that Gryphon out the window a long time ago and hoped it hit the designer on the head on its way down. No electronics are worth that much aggravation and down time. You might as well own a tube amp that mows through output tubes like a fat man mows through food at an all you can eat buffet.

 

[LL21]

its called having a limited budget and not being able to find sound i prefer more: Antileon combines power, tonality and extension. Still, may need to trade them in to someone for something else. I have been told krell 650monos (one trade-in option) might be a step backward...Might seek trade up to newer s/hand Antileon Signature.

 

[flez007]

its called having a limited budget and not being able to find sound i prefer more: Antileon combines power, tonality and extension. Still, may need to trade them in to someone for something else. I have been told krell 650monos (one trade-in option) might be a step backward...Might seek trade up to newer s/hand Antileon Signature.

I have not heard all recent Krell amps, but I have heard the 659 monos and the 600c and second your conclusion on considering the AS better.

 

[LL21]

Thanks for that...always good to get second opinions. Fingers crossed they find and fix it...i have also asked them to put in a Furutech fuse while they're at it. I have heard very good things about the Furutech fuses, and since its in for repair, may as well as get it put in and see what the fuss is all about.

 

[FrantzM]

lloydelee21

I must confess I didn't take the time to read your ongoing saga with the Gryphon amplifier.. It also seems you have a hum problem with another amplifier/system. Could these problems be related? It seems that the only thing these two systems/amps have in common is the Power source. Could you summarize your ongoing battles with your two different amps or equipment? I suspect it is a power quality issue. The fact that Gryphon could not replicate it weigh very heavily in this direction... Please give us a summary and more information (What XLR to RCA you are using, Type of IC, brand and even grounding scheme if possible)