Interesting that it is bias-sensitive... That could imply a stage with not enough bias, or too much, shifting it out of its normal signal range. Or, a bad tube or transistor, of course.
RFI could blow through the muting stages... You could isolate by using a shorting plug on the amp's inputs (disconnecting the preamp cables) to see if it still buzzes in mute (or not).
Thanks, Don. Someone else also said they'd experienced problems with bias levels and their Gryphon. In my case, i asked about this and they said they did not think that was the problem given their tests. They could not find the bad transistor...though somehow i suspect this is the problem. As for RFI...i spoke with Transparent Audio who makes my REference cables...they said the cables are shielded. plus, they said the symptoms seem to be more linked to the heat of the unit...tends to happen after watching movies at loud volume. Also tends to happen more and more often once it has started happening. Once you turn off unit for while (and i guess ship it for repairs)...it stops happening! Yeesh. Given that 5 loaner amps over the last 5 years in the exact same apartment without ever having this problem...still leads me strongly to believe it is a quirk of this amp. the recommendation was to live with it...and if it finally breaks down...then someone can positively find it and fix it.
lloydelee2, I just looked up about the amp's construction, it claims to be a dual mono design, which should mean completely separate transformers, rectifiers, and power supplies for each channel. I am now wondering if the problem is right down the other end of the amp, a bad connection or fault in a transformer or rectifier, the symptoms concur with this possibility, especially that the buzz stops when you reduce bias, immediately dropping the load on the transformer, say. This could be very hard to do, but it may be worthwhile getting someone to switch the power supplies between channels by putting in temporary leads to check this out.
May have been, and still be, a bad connection in the amp (bad solder joint or poor pressfit connector, for example). Those can be tricky to catch. With any luck, when they took it apart and put it back togetehr again they fixed it...
May have been, and still be, a bad connection in the amp (bad solder joint or poor pressfit connector, for example). Those can be tricky to catch. With any luck, when they took it apart and put it back togetehr again they fixed it...
One of my Accuphase amps has a bad solder joint. It plays fine for a couple days and then goes into protection mode for 2 days. It's been to 2 techs and they can't find it,although the last one said bring it back and h'ell fix it. It's a PTA but I've learned to live with it.
It did go intermittent in the rht ch but a transistor fixed that.
lloyde, did they change out all the heatsink insulators on the power transistors?
One other outside, at a stretch if my imagination possibility is that you are using a single-ended to balanced connector. If this is a typical thing, it should short pin3 to ground, and then tie pin2 to live on the single-ended input. If the Gryphon is a non-standard European pin 3 hot XLR input, this will be wrong, and you should be tying pin 2 to ground, and pin 3 to live on the single-ended input. I have no idea why something like this could cause crackling, but this is something about some European products that may have bearing.
1. Fas42 - I will ask...though they were highly confident it has "been given a new Christmas of parts replacement". As for bias...the key is if i lower bias, the crackling/buzzing immediately disappears, and if i then immediately flip back to full bias, the sound is still fine. Then it comes back after maybe an hour or so. it is literally just making a quick electrical "change" and it goes away immediately...and then it comes back. i can be in lower bias and flip to full bias and it will also be fixed.
2. Don - Yes, that is what they said...they might have gotten lucky and fixed it by accident in reassembling it.
3. RogerD - thanks. I am going to keep my Antileon and if it happens again...i will let it go until the transistor/circuit fails, and then they can just replace it
4. Gary - the adaptors were replaced by Gryphon directly...so presumably that should take care of your concern. Thanks for asking...this has been tricky so definitely appreciate your time.
In the end, i suspect it is (as most here have suggested) a transistor/circuit that is failing but not failed. and as it is tricky to find, i just have to hope it was inadvertantly fixed or it fails and then is fixed easily.
Fingers crossed on when it comes back. will keep posted!
Well, the Gryphon is finally home! Lets hope it keeps working. It sounds wonderful as always...rich, powerful, smooth with great extension. fingers crossed!
The unit's problem with the buzz has rarely varied over the last several months...once it gets intense use (mainly during video), it starts to go...first a random buzz for a couple seconds every few days, then every few hours, then every hour...the mute button has not had any effect on it. it is only worth noting because (with mute ON), the buzz still occurs, which means the buzz is something either AFTER the mute circuit or is something which mute cannot block.
i have continued to use the unit as per normal...so far no problems but frankly it is too early to tell. thanks for everyone's continued questions and interest!!!
Well, so far so good. its been over a week of daily playing. this is the first weekend of straight playing from morning to late evening...about halfway through that right now. fingers crossed...i am actually thinking of using a Furutech fuse in this. just to see what happens in terms of sound. it sounds bloody good right now, but i have heard only positive things about these fuses.
I still recall my time with the Anthileon/Elektra setup driving Avalon speakers.. some of the best I have had and sadly gone. I remember a long warm-up cycle thou... for about an hour to have them singing.
Yes...spot on!...my Gryphon sounds better in 1 hour from initial turn-on. However, the Zanden sounds best after 4 hours!!! Fortunately, the whole system sounds great after the first 20 minutes...but it consistently has this "startling" realism/sweetness and control after 4 hours. Hey, i get to listen to music while i work...usually 15+ hours on Sat and Sun, plus 3-5 hours each nite during the week. That's pretty darn good.
So 2 months later, (almost) no buzz! Here is the new added clue. i have only heard the buzz in the left mid-range channel twice now. Upon turning on the unit from cold start, i heard the exact same crackle/buzz in the channel for 1-2 seconds upon hitting the ON switch. It stopped by itself after the first 1-2 seconds of being on. Remember...it used to happen only after 15 hours of continuous use at high volumes (movie soundtracks)...when both my CJ pre and Gryphon were piping hot.
Does the buzz happening immediately upon hitting the ON button (for only 1-2 seconds) mean anything particular to any of our technically astute brethern here? Thanks as always for any advice.
(...) Does the buzz happening immediately upon hitting the ON button (for only 1-2 seconds) mean anything particular to any of our technically astute brethern here? Thanks as always for any advice.
I have owned a few amplifiers that had this characteristic - usual in amplifiers that do not have timed protection relays in series with the output stage. It is due to some ripple in DC not being filtered while the capacitors are charging after turn-on. As soon as they reach their normal operational voltage the hum disappears.
Designing an amplifier is not just assembling a circuit with good sounding characteristics - the designer must think of the transients at turn-on ad turn-off. If this is not considered in the project the amplifier can even destroy itself at turn-on and turn-off. Another important thing is considering that some parts can go faulty - you do not want an amplifier that burns completely just because a small transistor broke!
Thanks...i am prepared to assume for the time being Gryphon know how to design an amp well. Therefore, the query is whether this symptom of buzz just at initial turnon (and only in left midrange)...helps anyone ID a potential area to investigage deeper in the unit? or whether in reality it just means the same thing as all the other symptoms...that someplace, somewhere buried inside this unit is probably some innocuous little wire or transistor or circuit that is about to burn out and just has not done so yet. thanks.
