Any of you pros have an idea how to fix noises when turning the volume up and down?
Seems like dust got in thereā¦ l donāt want to damage the unit of courseā¦
Thanks
itās probably the pot failing, it was a common problem on the earlier Massdrop CTH. If itās like the CTH, the pot needs to be replaced and itās not a part you can buy.
Youāll need to contact Massdrop.
Thanks.
Failing as in it will stop working soon??
Itāll probably crackle indefinitely, but it could fail I guess.
Itās not user serviceable, the pots used are not generally available even if you were willing to solder a new one in.
Contact Massdrop, they are usually pretty good about replacing items like this.
Replacing the whole unit l assume?
Will write them and see what they sayā¦
Thanks
The 789 Potentiometer is cheap af, when I opened mine to check it was some knockoff Chinese brand trying to be Alps. I also had the same issue with the left channel being scratchy, and while the potentiometer IS desolderable, the damn volume knob is part of the pot, like itās not one of those knobs you can get off the pot, itās as if though the pot was soldered onto the board, and when the knob was put on, it was as if though it was designed to never be taken off, so you have to break the pot to get it out of the case or else the knob wonāt let you remove the pot, and then youād need a new knob too since again, the knob is part of the pot. Not bad if you keep the 789 since there are Vishay pots that can replace it on Mouser, but hurts resale value if you get bored of it and try to sell it on ebay.
Then again if you have a warranty, try sending it back, although theyāll still replace it with the same pot brand again.
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Thanks for the info !
It seems to me dust got in or somethingā¦ the crackles are not electrical in nature it seems.
lāve been tapping gently on the knob and around it on the housing and it actually helped[!]
Almost no crackles nowā¦ l will see what happens and if it gets worse.
I wrote to Drop and will get an answer on mon/tueā¦
Thanks ; ]
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It might not get worse, but itāll start crackling again. Itās that the potentiometer is probably dirty or has something on itās tracks thatās making that noise. The pot is cheap, but I recommend to let Drop handle it unless you want to DIY it, that option though will affect resale if you one day want to sell it. Try to specify if they can specifically select the best pot from the batch if they do take it in for a repair so that problem wonāt resurface again, and maybe handle the pot with a light touch for now on, since again, theyāre the cheapened part of the amp essentially.
(Technically it could function better/last longer/be more precise due to a better component, but since it isnāt Stock or āOriginalā, the value drops in this case for this particular amp, kinda the opposite for recapped tube amps/vintage SS amps, although even then there are specific capacitors that affect prices, like vintage with vintage caps and tube amps with Audiophile grade caps).
Sometimes better isnāt better, which is odd to say.
Nice!! Let us know what you think? And what are you coming from? How does it compare
Drop were very quick to reply and suggested a new replacement. Shipping covered by them.
l asked for a few more days to consider because going to the post is a hassle for meā¦and like you wrote the replacement unit might have the same problemā¦and l might pay customs AGAIN for the new unitā¦
Currently l love this thingā¦ and l donāt consider selling itā¦
So a few minutes ago l decided to try my luck with a small amount of electrical contact spray with a small tube directly on the pot through the vent.
So far ALL CRACKLING IS GONE ! ; ]
So far so goodā¦
Will wait a few more days and decide.
Thanks for helping
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Yeah the pot might have been cleaned using that spray, a simple but sometimes effective solution. Take a few days to see if that fixed it. If the issue pops up again however, consider sending to them for repairs, or maybe (and this is a stretch, but just another option), try to see if you can get a refund and get the 887 instead.
Same price, but I think the component quality is better, well besides theyāre essentially the same sound wise with some minor improvements in distortion in the 887, but about 100mW of power loss at similar loads in the 887 (Which is negligible).
Roll that option around in your head a bit, make sure that whatever option you do take is something that benefits you though. If the contact spray fixed it, then just keep the 789, and if the issue arises, well you have options.
Some very minor crackles only with IEMs persist. Not noticeable at all with full size headphones. l might be OK with this ; ]
Yesā¦ gave myself a few days to decide. Happy this didnāt happen with a $2000 amp ; ] No tears so far
Well $2000 amps generally have better pots, or possibly relay switched volume.
The volume pot is one of those things that tends to get a lot of attention in higher end gear.
The one in the 789 is on the poopy side, but there arenāt a lot of good 9mm/16mm pots, I know Schiit has alps custom make the ones in their small form factor gear.
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My gsx mk2 (now sold lol) had a dact stepped volume control and it was pretty awesome
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Yeah Usually DACT or some really high end Pots, Depends on what theyāre used for, etc. Well I mean there are some really cheap Film Resistor Pots that do a bang up job however, only 21 steps but thatās quite enough.
Bought something like this for my Darkvoice and itās very well centered when listening to Mono and no Crosstalk or anything. I think the resistors on the one I bought were 0.1% though.
Too bad they didnāt put this into the 789, then again the price would go up somewhat.
Oh also the Stock Pot on the DV is 250K but for Attentuators I found 10K to work the best.
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The Tone Board with the 789 sounds great to me so far. The Detail and spacious sound stage is something I do not get from my other gear. I am using HD58X headphones and the 789 really gives them something more than I have heard before from them.
The KTB is my 1st and only DAC (stand alone). I think it clean with good separation and a touch of warmth. the warmth I hear is compared to my PS Audio Spark100. The Spark is more analytical. I need some different cables to use my Micca Origen G2 and ifi nano bl as a DAC with my 789.
I am really enjoying this setup.
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Iām not sure about availability in all EU countries but the THX 789 now ships to Ireland from Amazon.com
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Do you think this bypasses customs? I.e. Is there a difference in getting this on amazon than on drop?
Iām afraid I canāt rightly say, shipping time and availablity should be better than drop though hopefully.