lee730
Headphoneus Supremus
- Joined
- Jan 9, 2011
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select all frequencies at 0
You must have done something right. He loves it with no eq and at eq -9.
select all frequencies at 0
@Alphaman I will take the risk, the sound is too good, thank you for the explanation.
Now that I think about it, most modern DAPs and smartphones and iPads, etc. do not have output protection. A few years ago, home components (CD/DVD players, etc) had output protection transistors (and a lot of DIYers removed them for improved sound). I think output protection is old-school thinking ... back when something blowing was more likely and would cause DC on the output (e.g., tube stuff) Today, QC and component reliability has gotten good enough that we can bypass old-school protection topologies. You'll probably get a new DAP way, way before the remote 0.1% possibility of a screw up. Still, you've got nice higher-end IEMs and the louder TeKMOD power-on thump is a little scary -- I've frankly never felt comfortable with the STOCK thump of T51. If you have DMM, connect some probes to T51 output and set it to DC in millivolts. Keep a sharp eye on it when you power it on. Write that transient value down and report back ... if you have the time
P.S. Transient may be very quick, so video-capture with your iPhone and examine the values in slo-mo playback.
I unfortunately have no volt meter to do that, but for me the easy way is to plug the IEM after, I power on the T51 one time a day in morning and I stop it in evening at home, I use USB to keep the charge during the day at my desk.
That's a lot of effort ... and now, the TekMOD produces even greater transients?!! Well, we all NOW know what the risks are ... so those that may be affected have been properly warned
Is just a popping noise, nothing to worry about.
Not saying you will ever encounter the worst-case scenario but in the case of DC, it's not what you HEAR that will kill your IEMs
Is this what you're using for the TekMOD HO and/or LO opamps?
Why not use purpose-built headphone amp ... also from TI? E.g., TPA6133A2. I think your customers would like this, but you'll have to solder at SOP level. Or you may also try a class-D amp for experiment.
Not saying you will ever encounter the worst-case scenario but in the case of DC, it's not what you HEAR that will kill your IEMs
THS4222 has a large quiescent current, body msop8, excellent data on the level of distortion and range of distortion.
I collected the amplifier on tpa6120 - it concedes noticeably to the amplifier on THS4222. Or you think, what if "vendor" assigned a chip as the naushnikovy amplifier, it because of it will be the best? It is simply ridiculous such to read.
Hi everyone
burnwaygta4, how much does the mod cost?
The THS4222 may have "excellent data" (PUBLISHED specs) but ...(a) those are specs done by the manuf. (or did you personally bench spec them, burnwaygta?); and (B), in any case, good specs do not always equal better sound. A good example of this is vacuum tubes vs. solid state.
I have compared the THS4222 to the TPA6120 and much prefer the latter. I design by ear and manuf. specs and my own oscilloscope measurements.
The manuf. datasheets of opamps publish full and complete schematics of high-performance (suggested) circuits, like TPA6120. These are circuits designed and tested by TI.com, so the have a lot of expertise backing them up.
burnwaygta: I suggest you post your full schematic here, in this thread, so you can get better feedback in this forum.