anyone want any more pictures?
T8000 when?
and here is a square wave at 1100vpp showing the attenuator does no damage to the signal
anyone want any more pictures?
yes i have listened to the koss vs kgsshv-carbon on the same headphones. many times. No i can't even think of a way of actually measuring the differences because the koss clearly tests better. If someone offered me $100k in any test gear i wanted, it would still be doubtful that i could corelate sound quality to any publishable numbers.
I think the idea is to show output swing is much better than with 100kohm ?Frequency response, THD FFT plot, IMD, THD+N vs power?
If that wasn't blind and level-matched listening, and you cannot even conceive of objective measurements that would explain your subjective claim that the Koss amp sounds 'awful', the most likely explanation is nothing more than just cognitive bias.
Can we get an accurate measurement of distortion at around 100Vrms to 200Vrms? Maybe a bit higher voltage even.the point was not to measure the thd of the koss box. I have to order special parts to do that.
the best for my setup would be 2x probes with a 1 meg input impedance. and 2kv trimmer caps.
could we measure the modern 727ii amp..
I think the idea is to show output swing is much better than with 100kohm ?
You are misreading the above measurement. Only second and third harmonics are counted in the total above, not total as THD in electronic measurements show. It is also an entirely different measurement system (chirp versus steps).Amir already did:
At 1kHz I see at least 60dB distance and some of the noise there may well be surround noises picked up by the mic.
I assume Amir used the SRM-007t for this so better than 0.1%.
The only thing null and void are your faulty conclusion and assumptions. As I just noted -- and you should have waited for me to comment -- you don't know which amp was used for testing. And that the measurements are not comparable since they were not meant for this use. Acoustic measurements of distortion are quite tricky anyway so you best not use one to validate/invalidate the other unless we have proper proof of correlation.Yes that is very useful information. This, along with the THD measurement solderdude linked to of the Stax SR-007 driven by the SRM-007t showing just 0.1% distortion at 1kHz, almost 20 times lower than the 1.8% from that amp alone shown here, are enough to confirm that the measurements in this review are null and void really.
700t has been offered for testing as well as another unit. I will have to decide whether I am publishing the results though or just testing for the owner and myself....Personally, I expect very similar results. Check this:
https://www.head-case.org/forums/topic/13627-stax-srm-700t-and-srm-700s/
"....Dropped by the garden (what's left of it) to see if the persimmons are ripe enough to pick and my heart fell to the ground. ..."
Fruit & Veg. are supposed to be good for you. Pretty well accepted truth universally, but I so clearly remember the first time I took my first bite out of a not-yet ripe persimmon. I thought someone had filled my mouth with slivers of glass. Youch! Talk about 'astringent'.
Amirm, what variety of persimmon are you growing? [yes, I realise I haven't uttered a single technical term on this forum. hehehe]