Head-Fi.org › Forums › Summit-Fi (High-End Audio) › High-end Audio Forum › The Stax thread (New)
New Posts  All Forums:Forum Nav:

The Stax thread (New) - Page 1469  

post #22021 of 24765
Quote:
Originally Posted by DefQon View Post

If you are looking at the same one I was looking at bundled with the 404 sig's. Those one's don't have a switch for 117,100, 240v operations the transformer inside is only 100v but I recall remembering KG and spritzer posting a picture while ago that some T1S do have a universal voltage bandai tranny in the circuit hard wired for only 100v with no voltage switch at the back but you can rewire it internally. I could be wrong.

 

All T1's have a voltage switch inside the amps except the very early ones.  Just remove the bottom cover to access it. 

post #22022 of 24765

Well no inside circuitry pics. Just these:

 

 

post #22023 of 24765
Quote:
Originally Posted by spritzer View Post

Upsampling started because Phillips had designed 14bit dac's which was the original CD standard.  With no time to make new chips they upsampled instead.  Arguably a far better ploy than what Sony did back in the day.  It is essential with delta/sigmas to decrease the error rate.  Saying that OS messes up the treble is simply not true though, that's like saying analog has higher resolution than Red Book.  In fact, how could OS do that as it is just a fixed multiplier? 

 

Plenty of DAC's that don't brickwall, in fact many high end dacs play with the brickwall and offer different slopes.  Removing it all together is a bad idea though and substituting for it with passive components is even worse.  That could be just me though as I believe in proper engineering, not hocus-pokus BS.  It's also nice to leave part tolerances out of the equation for unit to unit consistency. 

 

Completely agree that R2R's are superior and the only reason they are all but gone is cost, nothing else.  Even better are non chip based R2R arrays when properly implemented. 

I might be wrong here, but my understanding is that upsampling have nothing to do with bit depth?

Upsampling done by Philips back in those days is functioning much like a brickwall thus only requiring a lesser order low pass in the ouput in order to get rid of the Nyqvist image alias'; is that a misunderstanding?
 

As for OS messing up the treble, the poster might refere to the brickwall'ing causing artifacts in time domain?

post #22024 of 24765

Spritzer,  have you ever heard any of the Audio-GD PCM1704UK  DACs?  (i.e., Master 7, Ref 5.32)

post #22025 of 24765
Quote:
Originally Posted by thinker View Post

Head Amp three ratings with different phones with thinkers ears

100 =is best wich i have heard and behind me are probably the best amps

Stax Lambda series headphones 92/100  nice but not best

Stax Omega  85/100 too weak to get sonic bliss airy without punch

Grado   100/100 excellent

Sennheiser HD-800 110/100 mind-boggling probably the best amp for HD-800 under the sun

Audeze 100/100 nice/planars do not make huge differences with top amps

I prefer this amp with dynamics and planars.The performance with HD-800 is something wich should be heard by yourself

and best on 4 pin connection and interestingly stock HD-800 cable was best better than Cardas clear and Toxic cables on this amp.

This amp has long tone delay and colors and very silky magic mids wich is excellent food for HD-800.The 3D imaging of this amp is unbelievable

with HD-800.One of the most neutral and detailed tube amp around and easy to use.You can fry eggs on the top plate when the amp got it's running temperature

Is this amp worth the price?yes it is, it's much better than i described above

Coming back with this the ESH section OTL mode, it has developed through burn in process a lot (10 tubes), compared yesterday Head amp three with other Stax driver units the Head amp three plays now above all of them even with Omega series(very natural airy neutral).You get with Head amp three an amp wich plays on the highest level with all kinds of headphones.There is also an option on the back panel connectors wich are not in use but when other electrostatics appear (i hope Hifiman) the dummy connectors can be activated.I would say this amp is worth every penny.


Edited by thinker - 4/28/13 at 4:32am
post #22026 of 24765
Quote:
Originally Posted by DefQon View Post

Well no inside circuitry pics. Just these:

 

 


Just pop the bottom cover and you'll find the voltage switch.

post #22027 of 24765
Quote:
Originally Posted by soren_brix View Post

I might be wrong here, but my understanding is that upsampling have nothing to do with bit depth?

Upsampling done by Philips back in those days is functioning much like a brickwall thus only requiring a lesser order low pass in the ouput in order to get rid of the Nyqvist image alias'; is that a misunderstanding?
 

As for OS messing up the treble, the poster might refere to the brickwall'ing causing artifacts in time domain?

 

It's still 14bit but the over sampling and noise shaping created a digital feedback loop making the 14bit dacs perform better than the 16bit units Sony had. 

 

I think it has more to do with the massive roll off after 10K with most NOS dacs. 

 

Quote:
Originally Posted by milosz View Post

Spritzer,  have you ever heard any of the Audio-GD PCM1704UK  DACs?  (i.e., Master 7, Ref 5.32)

 

I wrote them off due to excessive fanboy BS back in the day but I'd still like to try one.  Kevin has one of their preamps and he likes it a lot. 

 

Quote:
Originally Posted by Tachikoma View Post


Just pop the bottom cover and you'll find the voltage switch.

 

Yup, underneath that 100V only sticker are all the voltages silk screened. 

post #22028 of 24765
Quote:
Originally Posted by spritzer View Post

 

All T1's have a voltage switch inside the amps except the very early ones.  Just remove the bottom cover to access it. 


Alright thank you!

post #22029 of 24765

Just to comment on the DAC discussion above (with spritzer and astrostar), just subjectively, the character of the front end digital source

does come through loud and clear with my 007t/009 system using an EMM XDS1 cdp. The unforced detail and texture and the ability 

to see into each musical object is pretty startling and has great emotional impact.

Maybe spritzer has some technical insight into the EMM (or any other very high end DAC's or player's) digital processing value and it's impact in a Stax system.

I'd be grateful to hear any comments on this.

post #22030 of 24765

Never been impressed by EMM players, either from a technical or a sonic standpoint.  His call to fame comes from the Museatex stuff, some of which was good but the rest was quite bad. 

post #22031 of 24765

OK, thanks Spritzer. 

post #22032 of 24765

 

 

Quote from Spritzer:

Upsampling started because Phillips had designed 14bit dac's which was the original CD standard.  With no time to make new chips they upsampled instead.  Arguably a far better ploy than what Sony did back in the day.  It is essential with delta/sigmas to decrease the error rate.  Saying that OS messes up the treble is simply not true though, that's like saying analog has higher resolution than Red Book.  In fact, how could OS do that as it is just a fixed multiplier? 

 

Plenty of DAC's that don't brickwall, in fact many high end dacs play with the brickwall and offer different slopes.  Removing it all together is a bad idea though and substituting for it with passive components is even worse.  That could be just me though as I believe in proper engineering, not hocus-pokus BS.  It's also nice to leave part tolerances out of the equation for unit to unit consistency. 

 

 

Quote from Wikipedia:
There was a long debate over the use of 14-bit (Philips) or 16-bit (Sony) quantization, and 44,056 or 44,100 samples/s (Sony) or approximately 44,000 samples/s (Philips). When the Sony/Philips task force designed the Compact Disc, Philips had already developed a 14-bit D/A converter (DAC), but Sony insisted on 16-bit. In the end, 16 bits and 44.1 kilosamples per second prevailed. Philips found a way to produce 16-bit quality using its 14-bit DAC by using four times oversampling.

The reason Philips oversampled was they had already designed an early 14 bit DAC, as you say, BUT this does not prove that the Sony DAC of 16 bits was below par to the Philips, and is probably the opposite in actual fact. All this does not have anything to do at all with Delta-Sigma chips and errors. The oversampling architecture (OS) was created by manufacturers to be able to design an effective HF filter at 20k-22.5k range that was 'deemed' required to block out sonic wave shadows are artifacts measured on oscilloscopes but in the upper human hearing range. This filter implementation has been proved by many leading DAC manufactures as false and not required, and lead to reduced sound quality proved in exhaustive listening tests as apposed to measurements. It is quite incredible how after 25 years or more of CD and the oversampling architecture of mainstream DACs, that manufacturers are finally listening to the SQ they actually hear, as apposed to a wave read out.

 

On Oversampling affecting the sound quality, many owners and reviewers prefer the Perfectwave DAC with OS tuned off, as do many owners of the Esoteric K-01. There is a change in the sound in those machines when changing the OS rates, so clearly it DOES affect the sound. We all used to think digital is digital, a copy is perfect, speaker cables are just wire etc etc. Time and again it isn't Many reports show upsampled digital is not bit perfect, and in real time, and then down sampled back to 16 bit? Errors, blurring, it all affects the SQ. I use the comparison of a 72 ppi image - upsampled to 288 ppi, then downsampled back to 72 ppi. Compare it with your original, and the OS image is not as sharp or as clean.

 

On Oversampling there are three camps

 

First camp stick to OS and think it sounds best.
Second camp have found NOS and maybe not sure how it works, but love the SQ and stay with it.
Third camp is those who have climbed halfway up the mountain, and decided to stop, and say they know it all, and slate NOS DAC designs without hearing any or many of the better ones out there.

I am in camp 2. I nearly left CD for good as I was so fed up with the digital sound and 'hi-fi' presentation. I am so glad I listened to NOS tubed DACs.

 

So, I must say it again, NOS DACs do NOT reduce the high frequency of RedBook. In fact, NOS DACs with the Brickwall filter removed should do the opposite? Also Tubed DACs do NOT guarantee soft sound quality or 'tubey' presentation. Some of the best audiophile amps available are tubed designs. Or is the BHSE crap now?

 

And finally, please guys, lets try some NOS DACs and make our minds up with quality experience preferably in your own system. It could be a revelation to you?

post #22033 of 24765

Spritzer thinks pretty highly of the BHSE amp. That said isn't redbook pretty much going extinct now, along with the sacd format?

post #22034 of 24765
Quote:
Originally Posted by astrostar59 View Post

So, I must say it again, NOS DACs do NOT reduce the high frequency of RedBook. In fact, NOS DACs with the Brickwall filter removed should do the opposite? Also Tubed DACs do NOT guarantee soft sound quality or 'tubey' presentation. Some of the best audiophile amps available are tubed designs. Or is the BHSE crap now?

 

And finally, please guys, lets try some NOS DACs and make our minds up with quality experience preferably in your own system. It could be a revelation to you?

 

NOS DACs that I've seen have a very slow roll-off filter.  I'm of the opinion that most issues people have with oversampling DACs aren't due to the oversampling so much as other aspects of digital conversion starting with the digital input. I do think that some music can sound glorious with a good NOS DAC though.

post #22035 of 24765

I've been thinking about transformers a little bit, Stax probably parallels a ~5000 ohm resistor with the transformers to keep the load somewhere between 8-20 ohms, but most people here report that the SRD-7 box sounds better when the speaker terminals are wired directly to the transformers, therefore bypassing said parallel resistor.

 

Assuming that an E-stat represents a totally capacitive load, the impedance is 1/(2*pi*frequency*capacitance). Given the 90pF capacitance of the O2, and a turns ratio of 1:25, and the load would be something like 140K ohm at 20Hz, 272 ohm at 10kHz and 141 ohm at 20kHz. So does this imply that most amplifiers don't really mind driving relatively high impedances? and the parallel resistor is unnecessary?

 

Edit: Herpa derp, I think I can answer this one myself. The resistor is in parallel with the headphones, not the primaries. Durrrr.


Edited by Tachikoma - 4/29/13 at 6:50am
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: High-end Audio Forum
This thread is locked  
Head-Fi.org › Forums › Summit-Fi (High-End Audio) › High-end Audio Forum › The Stax thread (New)