The solution for that is hardware volume control which I would advise to use.
The volume control is set to "hardware control" via the DAC but still adjusted through the software interface.
I could put a pot before the amp input but the amp would still be running open so presumably this wouldn't stop the off pop.
I'll try a switch to the amp board and see if it still happens as suggested.
No, adding a potentiometer does not make the amplifier running "open". On the contrary. If you add a hardware volume control like a potentiometer, stepped attenuator or any other quality hardware solution it will do exactly as you operate it. It will have low volume if you turn it down. If turned down powering on a source will give a plop but far less loud/damaging. Also switching on a device with full output will not result in possible shock therapy and/or damage.
Software solutions give many (too much maybe) possibilities but when something goes wrong you may have full volume on the loudspeakers which might be not their favourite pastime.
Software solutions give many (too much maybe) possibilities but when something goes wrong you may have full volume on the loudspeakers which might be not their favourite pastime.
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Software solutions give possibilities but when something goes wrong you may have full volume on the loudspeakers which might be not their favourite pastime.
Yes that is definitely my concern. Currently using old testing speakers until I sort it out.
There are quite nice stepped attenuators on eBay that will give you the safety. You can limit the volume to a certain acceptable maximum and still use the UI for software volume control.
The TPA3255 sounds awful before 70h. But after that... OMG! Really good!Effectively it looks huge...
I should receive my DAC today, and have been working on the crossovers of my speakers 👍
Will test this first 😂
I don't know if it's psychological, but something I have always laugh about, the electronic burn in, seems to really happen. I have now a lot more bases and definition in my sou d than at the beginning... I mean I had to set the bass at the maximum at the beginning to get a bit of them, now I'm back at the setting 0 position and I have a lot more...
Anyway, looking forward to install all the new staff this afternoon. I have already design/print the support 🤣
Will let you know.
BTW, TKD & Stepped Att. with resistors (Takman, Amtrans or Dale) do sound much better than ALPS. Even Tocos sound better than ALPS.
There is no evidence that burn-in of OPAs is of any significance for audible sound quality.
Same applies to some technical data - which might differ - but at levels far below audibility.
Certainly this does not apply to the golden ears who hear differences far beyond any measurements due to their extraordinaire unrivalled capabilities superior to the average deaf humans.
LOL, one must be deaf not to hear the difference... really.
The TPA3255 sounds awful before 70h. But after that... OMG! Really good!
Not sure if serious..😀
I'll be getting a few fresh 3e TPA3255 boards soon, which measurements should I perform straight out of the box and again after 72h of continuous use, and what differences will be visible in those measurements?
Also, what signal input should I be running in these first 72 hours - pink noise, or hip-hop, or..?
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LOL, one must be deaf not to hear the difference... really.
As a tech I also testify... even if it makes me loose credibility 😀
More in the field of electrolytic capacitors and coils but still. Also opamps that are just soldered in sound different after some time. Never found any difference in measuring but my ears did not lie. Well, I don't care what or why but I did learn to give devices some time powered on/playing before judging them.
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Never found any difference in measuring but my ears did not lie.
Eh, they do. That's the thing your brain is especially good at 🙂
Painting a racing stripe on your car can really make you feel it's faster ;-)
That's exactly why we *measure* things - to remove the whole psychological fuckery 🙂
Anyone that has used Black Gate caps in the past can tell the same. I am in this hobby/profession for more than 40 years now, I build stuff like a madman (quantity and quality) and absolutely no one can convince me of the opposite.
It is not always so but sometimes the phenomenon occurs (and then it is repeatable with the same parts). One can stubbornly deny it because it is political correct to do so and ignore it or one can just accept the phenomenon without understanding it. I also can convince others if I wish but I don't. I am also a member of the "we" club you describe so I know what I say.
If one wishes to deny then it is simple: just let new equipment or new parts settle for a few hours and then judge the device/parts. Simple. No loss of credibility, no shame, no difficult explanations with nasty naysayers to do.
It is not always so but sometimes the phenomenon occurs (and then it is repeatable with the same parts). One can stubbornly deny it because it is political correct to do so and ignore it or one can just accept the phenomenon without understanding it. I also can convince others if I wish but I don't. I am also a member of the "we" club you describe so I know what I say.
If one wishes to deny then it is simple: just let new equipment or new parts settle for a few hours and then judge the device/parts. Simple. No loss of credibility, no shame, no difficult explanations with nasty naysayers to do.
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I'm building tube amps since 1988, before that I have worked with HF transmission. I have build tube amps and several other electronics for private users, professional musicians (classical music) and recording studios. I never heard that somebody denied the burn in phase.
To claim that one can measure everything is pure arrogance and total ignorance of science!
To claim that one can measure everything is pure arrogance and total ignorance of science!
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When the first cables with direction markers/arrows came out many people claimed that it was pure marketing and nonsense, but if you say this in front of a cable manufacturer who has nothing to do with audio he will laugh you off!
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BTW, after over 30 years of experience I claim that solder joints need 48h to settle in. I had many customers in the last 3 decades who called me and said that it sounds hard or shrill after repairs. I had to tell the them to wait 2 days for solder joints and 50-100h for the new parts to settle in. All were satisfied, some of them were stunned about the change in sound.
The TPA3255 I have sounded totally shrill, uneven and ear piercing. I read here somebody claimed 70h burn in time. I calculated: Wednesday evening I would cross the 70h mark, then I sit down to listen and was also stunned about the quality of sound.
The TPA3255 I have sounded totally shrill, uneven and ear piercing. I read here somebody claimed 70h burn in time. I calculated: Wednesday evening I would cross the 70h mark, then I sit down to listen and was also stunned about the quality of sound.
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Anyone that has used Black Gate caps in the past can tell the same.
Jean-Paul do you like Black Gate caps?
IMO Black Gate N series and NX are/were unique. That is if you have the patience to wait for them burning in as they really do need time. Haven't found anything better except film caps when possible as they tend to be larger. Todays polymer caps are not to be compared with BG.
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BTW, after over 30 years of experience I claim that solder joints need 48h to settle in. I had many customers in the last 3 decades who called me and said that it sounds hard or shrill after repairs. I had to tell the them to wait 2 days for solder joints and 50-100h for the new parts to settle in. All were satisfied, some of them were stunned about the change in sound.
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Agreed. I have noticed the same with solder. In fact I would say that this effect dominates over component (eg capacitor) burn-in.
With my experience of now 70 yrs I have observed definitely that the earth is flat, and everybody who disagrees is a blind scientist 😛
If soldered correctly, the main contact is Not the solder, so any signal flow should not be affected by the solder.
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