Nelson Pass said:
Cascoding the AlephX would probably improve it even more.
Perhaps we make the 400.000 then.
/Hugo – cleaning up his drawing table... as well
So , to refer to Grey 's original schematic ,
Is it so , only make the value of R 11/R 33 selectable between two values , one for full bias and one for bias reduced ?
Is it OK to select a standby current of 20% of full bias ?
For me it would be 6A * 20% equals 1,2 A ?
On 48 V it is still 48 * 1,2 = 57,6 W ...and at this different value , the absolute offset would vary from full bias 🙄
Has someone tried it on an Aleph of a XA ?
Is it safe to change value of bias resistors CCS violently ( like a relay or a switch would do ?
Does someone have a schematic for watching diff DC at the outputs ? Coupled to the standby mode circuitry it would be a clever protection system for XA , think about yours drivers...you bought 10.000 bucks ... fried because of an internal failure ...
The standby mode could be activated with a single push like the one on the XA faceplate 😎
And also be commanded by a high diff. DC , which would shut down speaker connections .
I am sure there is a demand ... workers !!!
Any feedback passionately followed
Anael
Is it so , only make the value of R 11/R 33 selectable between two values , one for full bias and one for bias reduced ?
Is it OK to select a standby current of 20% of full bias ?
For me it would be 6A * 20% equals 1,2 A ?
On 48 V it is still 48 * 1,2 = 57,6 W ...and at this different value , the absolute offset would vary from full bias 🙄
Has someone tried it on an Aleph of a XA ?
Is it safe to change value of bias resistors CCS violently ( like a relay or a switch would do ?
Does someone have a schematic for watching diff DC at the outputs ? Coupled to the standby mode circuitry it would be a clever protection system for XA , think about yours drivers...you bought 10.000 bucks ... fried because of an internal failure ...
The standby mode could be activated with a single push like the one on the XA faceplate 😎
And also be commanded by a high diff. DC , which would shut down speaker connections .
I am sure there is a demand ... workers !!!
Any feedback passionately followed
Anael
Anael
I have a relay switching R19 in an aleph 5 (from 221k to 16k - refer to aleph 5 service manual) and it works fine. The relay reduces the bias down til 200mA, and results in a low thumb (not much, but sound like a little turn on thumb) in my system.
I don't see any reason why this shouldn't work in an aleph-x.
Regards
Hans
I have a relay switching R19 in an aleph 5 (from 221k to 16k - refer to aleph 5 service manual) and it works fine. The relay reduces the bias down til 200mA, and results in a low thumb (not much, but sound like a little turn on thumb) in my system.
I don't see any reason why this shouldn't work in an aleph-x.
Regards
Hans
We don't use relays in the XA's or the Rushmore XA amp,
and are not experiencing thumps or noise. We simply turn
off the bias to both the input and output current sources at
the same time, choosing the decoupling capacitances for
minimal noise.
and are not experiencing thumps or noise. We simply turn
off the bias to both the input and output current sources at
the same time, choosing the decoupling capacitances for
minimal noise.
Netlist said:
Cascoding the AlephX would probably improve it even more.
Perhaps we make the 400.000 then.
/Hugo – cleaning up his drawing table... as well
Here is the way to get the 400000.
Please can you explain what a cascode is good for and how it looks like, may be a nice schematic...
On my schedule for Zen Variations, I have been saving cascoding as a means of guilding the lily, but I don't mind if you guys go jumping ahead.
😎
😎
Nelson Pass said:
Hmmm... the Zen V4 was called the penultimate Zen -- ie 2nd to last, i have wondered what would be after it.
dave
Even if I had the skills to produce a cascoded AlephX, I wouldn’t present it on a dinner plate.Bernhard said:
We need 300.000 don't we? /Hugo - thanks Nelson, for not minding jumping ahead. 😎
Ok, I don't have the skills, but at least I tried.
Took me a few hours to read the cascode PDF and try to draw something.
I simplified Greys schematic, as only the cascode (at least that's what I think it is) is important.
At the risk of posting something completely ridiculous could someone tell me if this makes any sense.
No need to tell you it will be appreciated. 🙂
/Hugo
Took me a few hours to read the cascode PDF and try to draw something.
I simplified Greys schematic, as only the cascode (at least that's what I think it is) is important.
At the risk of posting something completely ridiculous could someone tell me if this makes any sense.
No need to tell you it will be appreciated. 🙂
/Hugo
Attachments
That's a nice approach, but would work a little better if you
use a voltage reference instead of resistors to bias the
cascode Gates. This way the transistors will not see supply
noise as much.
Also, you certainly can cascode the input transistors as well,
as was done with the X600 and X1000.
😎
use a voltage reference instead of resistors to bias the
cascode Gates. This way the transistors will not see supply
noise as much.
Also, you certainly can cascode the input transistors as well,
as was done with the X600 and X1000.
😎
Bernhard said:
For reference, an example of folded cascode applied to a differential was posted on this site sometime ago. I believe it came up in the X-SOZ or the X-bosoz threads. It should also be part of the supersymmetry patent.
Is there a performance difference between the folded cascode and a "regular" cascode like the one shown by netlist??
Found this post by Nelson:grataku said:
http://www.diyaudio.com/forums/showthread.php?postid=174696#post174696
Maybe this answers your question. 🙂
/Hugo - still reading patents...and patents...and patents.
Netlist said:
Found this post by Nelson:
http://www.diyaudio.com/forums/showthread.php?postid=174696#post174696
Maybe this answers your question. 🙂
/Hugo - still reading patents...and patents...and patents.
It gets me a little bit closer. Unfortunately I cannot bring myself to read patents, after the first line I want to throw everything out the window. I find that patents really describe everything under the standpoint of what one should not copy, explaining how the circuit works is beyond the scope.
