| jh6you |
| quote: | Originally posted by Nelson Pass (on page 19)
To measure the amount of feedback being applied to
this circuit, drive it with a load and a source having very
low impedance and measure the gain. Then drive it with
the finite impedance you will be using in real operation
and compare the two figures.
Divide the lower figure into the greater, find the log10
of this and multiply by 20 and you have the decibels. |
I am planning to measure the amount of feedback. However, since I am a COMPLETE NOVICE at this kind of measurement, I think I need somewhat detailed guides. Of course, the target is the XSOZV2 (on page 30). Could you give me a bit more specific instructionparticularly about the load and about the source having very low impedance? What are these to be? :ashamed:
Thanks. |
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| Henrik |
JH!
This is how I see it, if this can be of any help.
NFB applied in dB = (log((XHighGain/XLowGain)*10))*20
XGain means Vout/Vin.
An other more simple way, quote from Nelsons from his article "DIY OpAmps".
A simple rule of thumb about open loop gain and feedback is that the difference between the open loop gain and the actual output gain is how much feedback has been applied. If the open loop gain is 60 dB (X1000) and the actual output gain is 20 dB (X10), then 40 dB (X100) of feedback has been applied.
Gain in dB = (log(Vout/Vin)*20
Open loop gain is gain without the NFB-loop.
:) |
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| jh6you |
How to approximate the open loop gain? :sad:
How to approximate the closed loop gain? :sad:
How to calculate the open loop gain? :crying:
How to calculate the closed loop gain? :crying:
How to measure the open loop gain? :bawling:
How to measure the closed loop gain? :bawling: |
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| jh6you |
Hmm... Nobody stops my crying... Yeah, I have to stop of my own accord.
In order to inject an interest into this thread, I made two concept diagrams of feedback systems of XSOZV2 and Aleph-X, and compared them as follows. Do you see any error? Or any comment? |
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| jh6you |
Output capacitors
For an experiment, I added output caps to my X-amp as drawn in red. The caps are of 4700uF/35V/85degC ordinary electrolytic. First of all, these caps block me not to see DC at the speaker cable connectors. Most of all, however, my interest was in the sound effect.
I expected that the caps would degrade the sound. Yeah, it was so however surprisingly as much as I could draw a conclusion that I would keep them there. :)
Drinking a cup of coffee and listening to music... |
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| jh6you |
I made a small error to the above drawing. :(
The error was in connection to the 5k pot adjustment at the right side.
Here is the correct one. |
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| Bricolo |
| please tell us how it sound with and without caps :) |
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| jh6you |
There seems to be a subtle difference in sound. I however can not feel it clearly. Could I feel any subtle difference in taste between two different excellent wines? I do not think so.
I will keep the caps.
JH |
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| Bricolo |
| quote: | Originally posted by jh6you
Could I feel any subtle difference in taste between two different excellent wines? I do not think so.
I will keep the caps.
JH |
sure you can!
Excellent don't mean the same!
Both can be excellent, in different ways
it's the same for amps |
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| grataku |
jh6you
This xsoz of yours...
I could understand the initial experimentation, having the SOZ and -X-ing it up by adding a couple of feedback resistors. I completely fail to see the reason for this circuit to even exist. Why not just build the AX? It gives you -X- with a more firendly input impedance and saves you the money and the space of 4 output caps. I think this circuit is a waste of time, space and entropy. |
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| Henrik |
grataku
As I recall, no one hasnīt described the difference between the Aleph-X and an (specified) XSOZ, may be Nelson has, I donīt know. But I should be very surpriced if they had the same sound, since the Aleph-X consists of 2 gainstages and not just one, and also it does have 3 active currentsources in contrast to my version of the XSOZ wich only consists of passive csīs.
I am shure, that the Aleph-X can drive difficult loads and has a lot more power, so if this is what you are after then the Aleph-X must be your choice. But for my little listening room, 30 m2, I can hear some very loud music from my 7W XSOZ, and far from the point of clipping, and I am very happy about the sound it produces at this level. I have heard a lot of other amps, still no one as good as mine after the X-ing, at least ito my ears.
The Aleph-X does not qualifi as a Zen amp, that is an other reason why SOZ an XSOZ is still here. The low inputimpedance is no problem, when you turn your BOSOZ into a XBOSOZ everything will turn out just nice. An other reason is, if you already have a SOZ and BOSOZ, it is very easy to X them. For me it has ben fun to make the X design from SOZ and BOSOZ, I wouldnīt have ben able to make the Aleph-X, but with the expierience I have got to day, then may be.
I understand that you are happy with your Aleph-X, but what a boring world it woud be, if we only had the Aleph-X.
So the let us keep the audiofanatism outside dogmatisme an welcome all the differences.
By the way, when I get the time, I will try the Aleph-X, it is a terrific work done by Grey and others. |
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| grataku |
henrik,
I am far from thinking that we should all have alephX's. Actually quite the opposite. I don't know if I like that there are 1000 boards just like mine floating around!
Your minimalistic X I can understand, as it is true to to the Zen spirit with the passive CS and I bet it performs very differently from the AX.
The jh6you version with full blown active CS, without the benefit of the Zen4 input stage and now with output caps... I just don't know. |
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| jh6you |
| quote: | Originally posted by grataku
I completely fail to see the reason for this circuit to even exist. Why not just build the AX? It gives you -X- with a more firendly input impedance and saves you the money and the space of 4 output caps. I think this circuit is a waste of time, space and entropy.
The jh6you version with full blown active CS, without the benefit of the Zen4 input stage and now with output caps... I just don't know. |
:irked: Do you want to buy my impolite, rude, offensive response? ;)
I presume that X-SOZ of HenrikĄŊs will give us very good sound. I also presume that Aleph-X of GreyĄŊs will do the same. I get to have the impression based on the presumption, not based on the fact, because I have never experienced with my ears the sounds coming out of the two amps. Yeah, the Aleph-X might be the king.
The Aleph-X has two stages: the input diff amp stage, which is x-fied, and the balanced output gain stage with negative feedback to the front end. Meanwhile, mine has no input stage, but the single output diff amp gain stage, which is x-fied with somewhat negative feedback. Mine is considered simpler along the signal path. This is the key point I have thought about.
Do I need the input diff amp stage as in the Aleph-X? If so, my BOSOZ is the equivalent diff amp of the input line stage. Do I need the Ą°generalizedĄą high input impedance of XSOZV2? I do not really think so.
Do you imagine that the XSOZV2 gives us bad sound? If so, I should say that the balanced Zen V2 must give us very bad sound. The original Zen V2? Very very bad sound. The original Zen? Hopeless sound. Should I say so? No, I should not. All are untrue.
Have you ever heard of XSOZV2 sound actually?
I have not wasted any of time, money, space, and DIY-fun. The XSOZV2 is created 100% based on Nelson Pass design plus his in-house technology about simple circuit and its sound. I dare to propose Nelson Pass to consider XSOZV2 (or similar one) as a future Zen-X DIY-project, in respect of the sound...
JH
PS
Are you talking about the output caps? Please read this: http://www.diyaudio.com/forums/show...&threadid=10258
The output caps are used even to well known commercial products. |
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| Nelson Pass |
| quote: | Originally posted by jh6you I dare to propose Nelson Pass to consider XSOZV2 (or similar one) as a future Zen-X DIY-project, in respect of the sound...
|
I have several single-stage "Zen" balanced designs which
employ the "Supersymmetric" technique. Just about any
amplifier with an input diff pair can be turned into an X,
but it only seems to work well with simple circuits and low
open loop gain. (too bad, huh?)
No doubt some of these will become projects, but we are
still fleshing out our commercial offerings, and tend to
structure our DIY efforts for minimal conflict in this regard.
On the other hand, you guys seem to be doing a decent job
duplicating a lot of this stuff, and I don't see why you should
have to be particularly dependent on official copies from me. |
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| jh6you |
| quote: | Originally posted by Nelson Pass
I don't see why you should have to be particularly
dependent on official copies from me. |
... because only the official copy under your name could win total trustworthiness,
and could clean up the misleading if any.
JH |
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| Nelson Pass |
If I thought you guys were wandering far from the
path, I surely would jump in.
pass/ - likes to be the high concept guy like halo. |
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| jh6you |
Hi Guys, now, I would like to make a conclusion on the XSOZV2 shown at the top of this page.
Power rating:
(a) With the circuit shown above
- Total Mosfet power dissipation: 85W/Ch
- Output power: 15W/Ch, 8 Ohms and 8W/Ch, 4 Ohms
(b) With R16 reduced from 1.5k to 700 and others remain the same
- Total Mosfet power dissipation: 85W/Ch
- Output power: 30W/Ch, 8 Ohms and 15W/Ch, 4 Ohms
(c) With R0 reduced from 0.5 to 0.33 and R16 increased from 1.5k to 2k and others remain the same
- Total Mosfet power dissipation: 130W/Ch
- Output power: 30W/Ch, 8 Ohms and 30W/Ch, 4 Ohms
(d) With R0 reduced from 0.5 to 0.33 and others remain the same
- Total Mosfet power dissipation: 130W/Ch
- Output power: 30W/Ch, 8 Ohms and 50W/Ch, 4 Ohms
I have no other data.
For your info, my current version is (b).
Thanks for your having shown your interests in the XSOZV2.
JH |
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| ralf |
for all who are in doubt of the quality of the Sound of X soz , combined with X Bosoz: BUILD THEM, THEN YOU CAN FIND OUT !
meanwhile i tested my ones against 9000 Euro Octave tube amp pre/amp combination and Luxman c03/m03`s:
the x soz is one of the best i ever heared and im` in search to find something better, but did not find until today!!!
the only thing is that the speakers must fit to theX Soz,.
i have less time in moment, but the parts of aleph x still lie in my box. i`m shure, that aleph x ` dont sound that much better. ...soooon i`ll know
regards,
Ralf |
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| gnomus |
| I agree SOZ(have not xed yet) is hard to beat when matched to the correct speaker. Indeed, when I look at a circuit for an Aleph or AlephX I see SOZ attached to various electronic ornaments(brilliant Pass patents) to make it more efficent, speaker friendly and I would guess to retain the SOZ's overall character. |
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| stefanobilliani |
No title can be more apropriate.
Well , I'm now with the x-bsoz .
It is somehow unforgettable the sweet and non agressive musical narration that this circuit is capable to .
Every listening session become an event I find .
A short list of my set up:
CD/SACD Sony scd xb 940 The I/V converter is the PassLabs D1
This converter is the best I ever listen to from a digital source.
My old Headphones Sennheiser HD 520.
As you can read at the bottom of the .pdf file Henrik x-bsoz and x-soz this circuit is " capable of driving hp at 60ohm se or bal " True!
I feel my HP happy with it !
The thing that more than others impress me is the bass region :
articulated , dinamic , delicate ; it passes trough my ears and reach the bottom zones of my body without fatigue, a sweet flow of sensations.
The equilibrium between the stages is "another planet " the instruments are reproduced in all their armonics contents , round tonalities and intriguing textures.
A big value for this kind of performance is to take back at the D1 I/V stage , no doubt.
The Henrik X-bsoz is just what you need after for an exceptional - new - good listening experience .
GREAT SHOT PASS DIY !
A would refear of just one record that I liked recently and is from
Telarc , a direct stream digital recording (on cd) by Michel Camilo named TRIANGULO a trio of piano bass and drums .
The piano takes up the scene with a unexpected coherence and dinamic contrast.
Finally: highly recomandable , good sounding circuit .;) |
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| vit |
henrik,
need to know the voltage ratings for C202,C201 in henriks xboz. :cool: |
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| Henrik |
Hi Vit!
You are safe with 10-16V, and if you ar using polarized caps, plus goes to the drains.
At 19V rails you should have around 5.5V DC at the drains, and 0V DC at the inputs. So in theory you will have 5.5V DC across the caps which is their min voltage range.
I have some Blackgate type N at 6.3V I tend to use, but at frequencies below 1 Hz, the voltageswing around the caps are 8V. I dont expect that low signals comming, but just in case I will experiment with some 6.2V zener across the BGNīs for protection, this will also suppres those low freq signals. But one has to be carefull not to get DC at the inputs. How this will affect the sound, I donīt kow I still have to try. |
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| vit |
hi henrik,
is the xsoz&xbosoz really x:ed? some guys here in sweden says it's not.
i'm building it anyway ;) |
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| Bricolo |
| quote: | Originally posted by vit
hi henrik,
is the xsoz&xbosoz really x:ed? some guys here in sweden says it's not.
i'm building it anyway ;) |
I also have difficulties to find some X in them |
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| jh6you |
| quote: | Originally posted by vit
some guys here in sweden says it's not.
|
It seems that they misunderstand the X. ;)
JH |
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| Henrik |
Hi Vit and Broccolo!
They are as Xīd as possible, and in the most simple way possible.
Take a look at my description http://www.diyaudio.com/forums/show...5&pagenumber=46, read the patent and also read around page 17 in this x soz thread.
Because you donīt se X, as a graphic sign in the scematic, it does not mean it isnīt Xīed.
X or supersymmety is hard to grasp, but try again.:nod: |
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| Bricolo |
| quote: | Originally posted by Henrik
Hi Vit and Broccolo!
They are as Xīd as possible, and in the most simple way possible.
Take a look at my description http://www.diyaudio.com/forums/show...p;pagenumber=46, read the patent and also read around page 17 in this x soz thread.
Because you donīt se X, as a graphic sign in the scematic, it does not mean it isnīt Xīed.
X or supersymmety is hard to grasp, but try again.:nod: |
the problem is that I don't see X like on the aleph x, in pther words: feedback from one side to the other
but mr pass's patent don't either
there are different forms of X |
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| Henrik |
| The feed back from one side leaves the source as a sourcefollower and appears at the other source seen as coupled in common gate and thereby appears noninverted at the drain of the other mosfet. There isnīt differet forms of X, itīs all about the same. |
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| vit |
henrik and all the others
thank you guys for the support
den - swe 3 - 0 |
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| gnomus |
In the X feed back loop for XSOZ. Does it matter if R212 1K and C201 220uF are reversed. Or must R212 be soldered to the input and C201 soldered to the output.
Thanks. |
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| ralf |
Hi,
it seems that xsoz thread is a bit death, last time...
i wonder why no one of the thousands of diy guys here didnot build a xsoz and a alephx to compare.
i just bought two alephx pcb`s of carpenter (hope the arrive me, soon)
i hope i get them working, then i will tell you about my expieriences.
I have one big question to you, all:
as you know i use henriks Xsoz and Xbsoz with speakers at about 90 db efficiency.
but the power doesnt be sufficient, even if i turn the voltage of the xsoz to +-35 volts, that should be about 18 watts.
when i connect my Hiraga le monstre (not balanced) to the XbSoz, the power is more than twice. i can turn the volume knob half-back. And the monster has only 8 watts.
can someone explain me that??
greets to henrik and jh (and all the others) |
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| till |
| quote: | | i wonder why no one of the thousands of diy guys here didnot build a xsoz and a alephx to compare. |
For me the reason is easy to see: big heatsinks are very expensive!
I have the alephx PCB, but for this reason i did not start building until now. |
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| ralf |
...because of the big amounts of heatsinks?
the alephx or the xSoz?
wo hast Du die alephx pcb`s her?
from where are your alpeph x boards?
from chad?
greets, Ralf |
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| till |
ralf, in case i find a good and cheap source for affordable and really big heatsinks i would build alepx and SoZ or xSoZ. In my experience with different Zens, heatsinks was the most expensive part for building an amp.
I ordered them from Fischer.
Ich hatte die Platinen bei der großen alephx PCB Bestellung von Chad geordert.
At the moment i canīt go on building expensive stuff because i put so much into my speaker project.... |
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| ralf |
| quote: | Originally posted by till
At the moment i canīt go on building expensive stuff because i put so much into my speaker project.... |
...i know.
i hope my wife will not shoot me for the money i waste.
Since i only trust my ears i am building diffrent amplifier designs - not only the ones from pass-forum (excuse me).
and as told, the hiraga monster is very, very very good. (and very very cheap to build.
if battery psu and high grade parts will enhance the sound as i hope it will outperform the XSoz...
i am bulding a JLH design , too.
when i have checked out all of them i make my decision and build the end version of "My amp"
greets,
ralf |
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| stefanobilliani |
| quote: | Originally posted by ralf
And the monster has only 8 watts.
|
Is it a matter of gain with the XSOZ and XBSOZ ?
Isn't the Hiraga a push pull design or I'm wrong ...?
Anyway with the B&W 90db/1w/1meter 2 way system I obtain the best results with biamplification ,when talking of low efficiency
designs like son of zen, in particular IMHO the mid/high freq are usually (even if perfectly sweet and detailed) penalized by the passive crossover that acts strongly around the drains of the diff-pair(SOZ) .
Never had problems with volume, by the way , remember that your X version only controls the gain and do not reduce distorsion.
Try build a folded cascode version and let me know......
:devilr:
Billiani / Had enough of push-pull |
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| Henrik |
Magic, i thought this thread was dead long time ago!
Gnomus:
You can reverse R212 1K and C201 220uF, no problem.
Ralf:
I remember you had this problem| quote: | as you know i use henriks Xsoz and Xbsoz with speakers at about 90 db efficiency.
but the power doesnt be sufficient, even if i turn the voltage of the xsoz to +-35 volts, that should be about 18 watts.
|
The gain in my setup is perfect for a 8 watt XSOZ, but you probably need to increese the gain in order to exploit the extra voltage swing your PSU at 35V can give you. I am using a PSU at 19 V wich is more than sufficient to drive my around 90db speakers.
Hi stefano!
At the moment I am building an X analogtstage in my CD, but unfortunately I donīt have so much spare time for the time beeing.
Greets to all - Henrik. |
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| jh6you |
| quote: | Originally posted by ralf
... about 18 watts.
And the monster has only 8 watts. |
Hi Ralf
As you know very well, the power is "the rate" at which the work is done, or at which the energy is transferred. In my opinion, how fast the amp reaches its output power is another matter and it is up to the gain value. If there are two amps having the same maximum output power of 20W, but different gain values e.g. 4 (12dB) and 8 (18dB), then the 12 dB amp would reach its power at lower speed than the 18dB amp. In consideration of this, I sometimes need to adjust the step values of the volume attenuator of my pre amp.
JH
PS. I do less care of the output power, the gain and the position of the volume as long as they work the music to melt into my heart. |
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| ralf |
| quote: | Originally posted by jh6you
PS. I do less care of the output power, the gain and the position of the volume as long as they work the music to melt into my heart. |
...you`re right, but when i must turn my volume knob to full output and the musik doesn`play loud enough (i dont hear very loud musik), the its too less.
But i didn`try to increase the gain of my xbosoz because i`m afraid the superbe soundquality will get down.
Henrik, how moch, di you think i can increase the 39k resistor, without loosing quality?
greets,
Ralf |
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| Henrik |
Hi Ralf
I am in a bit of a hurrey, but some 100K shoud be okay, as the feedback is quite high.
I will try to simulate to night, within 10 hours or so. |
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| Henrik |
Hi Ralf!
I just took a dive into the problem.
One of the challanges in this project were to keep the -3db highend roll off over 100 Hz, due to the input capacitance of the fets. To keep this R122 and R123 needs to be as low as 39K, so donīt raise their value, I have done a lot of experiments on this, and not keeping this standard is very audible in the negatieve sence.
So to get higher gain, lower the input resistors R120 and R121 to 6.8K or 5.6K, the only prise paid is the lower input resistance, singleended 4.7K or 3.3K. But be shure that your signalsources is capable of driving these loads, most Solid State equipment should be able to do just ok.
Regards |
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| Henrik |
OOPS!
-3db highend roll off over 100 KHz, not -3db highend roll off over 100 Hz. |
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| ralf |
...thanks i will try , soon
greets,
Ralf |
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| superstition |
Does anybody know how to calculate (not measure) the X-SOZ' input impedance?
All I know is that it is influenced by R212, R213, R214 and R215...
regards
superstition |
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| vit |
Hi Henrik,
Now it's a real pleasure to listen. Yes, it lacks some bass, but my Proteus won't play much below 50Hz anyway.
With the original SOZ it didn't matter if you were listening to mp3's or bad recordings, everything sounded great. With the xsoz those recordings sounds terrible. It's so revealing! It deliver no magic FX like the soz, only the truth, the whole truth, and nothing but the truth, And that might hurt sometimes. But with quality classical music, recorded with few mics you get the whole concert hall in your living room! The 3D-imaging is amazing.
The coldness has disappeared, or as you said, I've been used to the sound. Maybe it's the same feeling when you go from cheap full range speakers to good stand mounted speakers. First you are disappointed about the lack of bass. A week later when you hear the true quality, you would never go back.
A pair of Black Gates after the regulation would be nice, but they cost a fortune. I rather go for less expensive standard gear. Do you use 63V or 100V caps? 63V is dangerously close to 60V :cannotbe:
A X-output sounds nice, but I think I need a whole new cd. My Rega have a increasing TOC-reading problem. A cd pro2 + TDA1543 dac would suit me perfect. I could try different output stages. Passive, X, D1, or a x:ed D1 =) But with a passive I/V you get a system with only two gain stages in signal path, that sounds tempting.
A month from now I'll be studying basic and analogue electronics. Yippie
Yours sincerely,
Vit aus Schweden |
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| Henrik |
Hi Vit!
Once again congratulation!!!
I think sometimes, when you hear some bass which isnīt detailed or grainy, you feel itīs a kind of deeper, but it isnīt. On my system I have plenty of verry deeeep bass, without the feeling of a blerred bass which my former soz had, althougt it sounded good. I think the XSOZ is very hard to beat when it comes to vocals and acoustic instruments, but even hard rock sounds very nice.
When I was talking (we e-mailed yesterday) about Black Gates after regulation, I ment not for the xbosoz but actualy my xsoz, wich is powered by a single rail regulated PSU with a virtual groud to bias the fets. I am using two Blackgates at 4700uF 50v, one for each channel.
Happy listening.
"A month from now I'll be studying basic and analogue electronics. Yippie " Sounds great!
Regards |
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| ralf |
Hi,
i still live...
have you experiences about black gates?
where can i place them with best results?
greets
Ralf
p.s:
i do no longer use my XSoz. i changed away from Pass and used JLH classe a amp. |
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| Henrik |
Hi Ralf!
Long time no see!
Yes - I realised you were lost and far away from the true pathway to heaven!!
But anyway I hope you enjoy your JLH.
After regulation is the best place to put those Black Gates, and if you can afford, use them even before. They do make a difference.
I have ben thinking of the problem about the gain in soz and xsoz as we have discussed before, i have done som sims, and i think when you are above say 10w you need an inputstage with IRF610.
Regards from heaven! |
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| ralf |
next week a guy comes to me who uses a hiraga monster with battery supply.
i think i can use one for my JLH. If the battery psu sounds rellay better i will go for that.
i think (but dont know) that battery option is better than every standard PSU even with Black Gates...Any way i bought some Black gates today to test....
Ah, i forgot to say that i meanwhile tested Caddock MK32, dale RN60, Audionotes and next time the horrible expensive Vishay 102k resistors.
All of the tested ones- much more better than standard resistors.
(i remeber you build your xamps with audio notes)
Greets to the pass-friends |
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| Peter Daniel |
| quote: | Originally posted by ralf
Ah, i forgot to say that i meanwhile tested Caddock MK32, dale RN60, Audionotes and next time the horrible expensive Vishay 102k resistors.
|
What are your observations regarding those resistors? Personally, I liked Vishays the least. |
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| Henrik |
Hi ralf
Who said any thing about standard PSU?:o
But ainīt batteries big trouble in class A at several amperes?
You remembered correct, I am using audinote resistors, allthough I havenīt tested them myself pice by pice, you know, with all the improvements i made with better parts in one turn, it just came out better than the first one, made with crappy parts. It was hard for me to recognise which part made what? But thanks for your point of view on resistors, i believe they sound better than the useually once.
I will follow you and the batteries at the JHL forum, if you post.
Best regards from a Pass-friend of yours.:) |
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| Henrik |
Hi peter
Have you ever tested audionote resistors pice by pice?
Just curious. |
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| Peter Daniel |
I used them in my recent monoblocks and they sound fine. I didn't notice any obvious signature about them like with othe rresistors, but still didn't really compare them against other brands. I have a feeling they may sound similar to Caddocks, but smoother.
Vishays S102, are very soft sounding, too soft for my taste. Rikens, OTOH are a bit bright and a bit harsh maybe, but overall quite good, but not totally neutral. Caddocks when used in feedback loop, produce better soundstage and less obvious signature. I will try compare those tantalums soon, and they might be my future choice. |
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| gnomus |
| I use Vishay S102 nude resistors from texascomponents.com They cost less than Percy audio. And you can get them in .005% if you need to. But it cost more for those. I use 1% in SOZ/XSOZ. Since ther are so few resistors it's not a big expense. I do not find them soft. I found out about the nudes. Because they are used in my AHT phono stage. One of the best phono stages ever made. I have used tantalum too. And those are good. Not as neutral. A bit of a more full sound. Not as clear in the highs. I could live with either. In the SOZ circuit with so few parts you can here the difference in parts. In other more complex circuits it can be hard to tell what is doing what. Unless the change makes it a lot less musical. |
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| Peter Daniel |
There is a forum member who sells S102 at $2 and recently I think they went up to $3 per piece (even 200k which normally sell at more than $25).
I compared those resistors in a feedback loop of a gainclone and in a series input connection. I also tried them in Aleph X feedback loop. Whenever I put them in, they substantially softened trebles, comparing with other exotic resistors. I didn't really like the effect.
I read comments that nude Vishays are better sounding as less damping is applied (because of no case). |
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| ralf |
hi Daniel, Hi Henrick
in the last year i made some experiences with Hiraga le monstre and JLH.
both sound better the better the components you use , are.
In comparison to X-soz/bosoz , which are not so sensitive about the used components.
The question, which resistor sound best is hard to answer. i think it depends on the amp you use and the other components like Cd Player, cables etc.
Fact is, that if you want to build somewhat very good sounding you have to use high quality parts.
Battery PSU:
A good friend of mine builded the hiraga amp with conventional psu and with battery option. He told me, that battery option sounds better in all aspects.
(this friend comes next weekend to me and takes his amp with)
This friend builded several pass amps last years, one of them zenV4 with high grade parts, and he sold them after constructing his hiraga with battery option!
Henrick: with standard psu i mean "non battery psu"
to the question for the 2-3 amperes quiscent current of the JLH: youre right, but the answer is :you need big batterie to be able to play about 5 hours min.
I am in search of best musik reproduktion and cause of this i dont matter about the size of an amp.
Daniel:
since oyu are the man who build an amp faster than anyone reads the schematics: would it not be an intersting project for you to build a JLH? :nod:
Regards,
Ralf |
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| gnomus |
All I have read about battery supplies have few consistant traits.
Very quiet, smooth musical sound.
Lack of dynamics.
Not all types of batteries work well.
But, I am very interested in hearing the difference in the same amp when you compare them.
I also think you could make a big supply with a huge choke input and lots of caps that can be almost battery like. Something I am working on for SOZ/XSOZ.
The most limiting facter is the power output devices. These have the most noise and distortion in a circuit(as Mr. Pass stated). The way I see it. A really quiet supply that can deliver all the power needed without being taxed helps. But, has it's limit do to the ouput devices.
Where will you be posting your results? Is there a separate thread? |
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| Peter Daniel |
After playing with GC for some time, it would be hard for me to find a better sounding SS amp (in some aspects of sonic satisfaction of course). Do you have a link to JLH?
As to batteries being better, it probably depends on your mains condition and will vary greatly with location. I'm using baterries with my DAT recorder and comparing to a regular PS, it is slightly better (highs are smoother) but not that much. |
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| ralf |
..no i will not post in a separate thread.
there are many posts about the battery supply
My Friend had used a good conventional Psu for the hiraga first, and then he updated with battery supply. (2 farad caps after each battery!!!)
He told me, the sound improved in all aspects - also in dynamics!
I konow him good ind trust his statements, but in weekend of Okt, 12 i will exactly know...
Ralf |
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| ralf |
| quote: | Originally posted by Peter Daniel
After playing with GC for some time, it would be hard for me to find a better sounding SS amp (in some aspects of sonic satisfaction of course). Do you have a link to JLH?
As to batteries being better, it probably depends on your mains condition and will vary greatly with location. I'm using baterries with my DAT recorder and comparing to a regular PS, it is slightly better (highs are smoother) but not that much.
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...right, not that much, but much enough for him to fire his amp with batteries. Often the last pieces of better sound cost the most money.
here the link:
http://www.tcaas.btinternet.co.uk/
look for "JLH update"
...but i believe you, that your gainclone is one of the best sounding amps....if i have the time i would test..perhaps later...
Ralf
ps if you plan to build: only use Mj15003 of ON, availlable at Farnell.
All transistors are matched.
Dc offset is a bit tricky to adjust.
i use jensen copperfoil in oil cap as couppling capacitor. you can hear each capacitor and resistor you change. |
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| Henrik |
Hi ThomasS
Welcome on board!
I tried to e-mail you, but you have disabled the opportunity to recieve email through the forum. If you enables emails on your account i will answer your question.
But what do mean by "intgr. Xsoz" ?
Regards |
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| moe29 |
i've been staring at Henrik's schematic of the x-soz for so long that
i finally had to give it a try. These are two mono blocks putting out
5 watts each.
first listen tonight and all i can say is amazing soundstaging
and crystal clear... and that was before warming up for an hour.
Thanks Mr. Pass and Henrik! |
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| moe29 |
| some interesting point to point wiring... :) |
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| Mad_K |
| quote: | Originally posted by moe29
.
first listen tonight and all i can say is amazing soundstaging
and crystal clear... |
-That sounds about right! (Until you try to make it deliver more than 5W...) -Extremely clear and transparent; resolution in the mids and top is scary!
I am in the progress of making a pair of 15-20W monoblocks of the XSOZ monster. As I have buildt a few SOZ's my expectations are quite high to this new X-version. If X-ing the SOZ is anywhere near Xing the BZLS......:bigeyes: ;)
PS -Congrats moe! When will they get a decent chassi? |
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| Netlist |
Nice job Moe.
Any particular reason for the placement of your chokes?
Was this the best position to avoid hum?
Personally I would ply the caps further away from the mosfets on the heatsink.
Again we will have to push you a bit to make a decent enclosure :devily: but then again I'm sometimes as hopeless as you to finish a project ;)
/Hugo |
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| Variac |
I've noticed a distinct lack of stupid questions lately.
To remedy this here is my question:
Is the wattage output of xSOZ relative to rail voltage the same as a regular SOZ as shown on the Pass website?
I ask because the X Aleph appears to use about half the volts for the same output |
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| Mad_K |
| quote: | Originally posted by Variac
Is the wattage output of xSOZ relative to rail voltage the same as a regular SOZ as shown on the Pass website?
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yepp; dead on! (as long as you use 8ohm resistors..)
;) |
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| moe29 |
I should say that this was a "proof of concept" project for me. I
wanted to see if i could build and x-soz and have it work. Thus,
the layout, the parts, etc. I am truly a neophite in building amps -
so please take my construction with a grain of salt! :)
(see Mads_K's P to P work for inspiration!)
As to the layout of the inductors - i've read on the Forum that when
placing two inductors close to each other, it's best to have them at
90 degrees. I have no hum problem at all. The amp is dead quiet,
with an unmodified BOSOZ as the pre.
I was trying to keep my point to point wiring short, thus the placement
of the 220uF caps near the FETs. I guess i was influenced by those
building GainClones and their point to point work. They have
power supply caps sitting right on top of their chips!
A lot could be done to make these amps "better" i suppose all the
same type resistors to start (!) and maybe a Black Gate cap for
the 220uF, some bypass caps in the power supply, etc. Maybe if
i can stop listening long enough i'll do that ;)
btw, i have no WAF problems, nor pets, thus i can get away with
having an amp like this sitting in my living room!
m. |
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| Henrik |
Hi Moe29
Nice work. Welcome to the world of X-SOZ.
Try x-ing the bosoz or at least raise the value of the output caps at your bosoz to about 50 - 200uF.
I am so buisy at the moment, I will be back later on.
Regards Henrik. |
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| Mad_K |
| Henrik, wouldn't this be a little easier? :rolleyes: |
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| Mad_K |
| quote: | Originally posted by Mad_K
Henrik, wouldn't this be a little easier? :rolleyes: |
-I guess not, since 4R25 and the like can be hard to find...:o |
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| Nelson Pass |
| quote: | | Originally posted by moe29 btw, i have no WAF problems, nor pets, thus i can get away with having an amp like this sitting in my living room! |
My wife likes giant horns and monstrous amplifiers. :cool: |
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| Mad_K |
| quote: | Originally posted by Nelson Pass
My wife likes giant horns and monstrous amplifiers. :cool: |
-You lucky guy! ;) |
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| Henrik |
| quote: | Originally posted by Mad_K
Henrik, wouldn't this be a little easier? :rolleyes: |
Yes, but as you mentiond, 4.25 Ohm resistor is hard to find. The reason I derw the scematic the way I did was to visualise the changes from Nelsons original scematic.
Regards |
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| Variac |
From my online dictionary:
monstrous: Shockingly hideous or frightful.
Exceptionally large; enormous: a monstrous tidal wave.
Deviating greatly from the norm in appearance or structure; abnormal. Of or resembling a fabulous monster.
seems to cover it............About the way my SOZ is shaping up
I dunno if the Pass amps want to be known this way! |
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| Nelson Pass |
| I'm not shooting for the Bryston look. :cool: |
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| Variac |
Hey Moe 29,
Maybe you should do what I was considering for the SOZ- mount everything onto a piece of plywood and hang it on your wall.
Maybe monoblocks, hang one by each speaker.
"It's scupture/It's an amp!/It's a drain cleaner"
Wait ! Wait!!
Mount each amp channel on a larger piece of ply, but not in the middle. Then cut a hole in the middle and put in a full range driver.
Add braces to support it on the ground and:
Viola! Self powered open baffle speakers/sculptures
Mark |
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| moe29 |
After a couple of weeks of listening to my Aleph 2's i went back to
my X-SOZ tonight... what a beautiful sounding amp. At 5 watts it's
not as visceral as the Aleph 2's, but it's crystal clear and dead
quiet... just beautiful to listen to. Now i know why Mad_K is
building a 20 watt version - i was thinking the same thing tonight,
a little more power and look out! I would love to compare a
20 watt X-SOZ to a 25 watt or so Aleph-X. Because simply put, the
X-SOZ is the sweetest amp i've ever heard. |
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| stefanobilliani |
| quote: | Originally posted by moe29
- i was thinking the same thing tonight,
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Yeah , the though of a 20w SOZ never leaves my mind .... :cool:
| quote: | Originally posted by moe29
X-SOZ is the sweetest amp i've ever heard. |
Indeed . :nod: |
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| Henrik |
Hi moe29
Glad you like the xsoz.
But if you are driving it with standard bsoz two diffrent things happens.
1) Too much (IMO) x-feedback because of the higher outputimpedance in the standard bsoz.
2) If you have 10 uF at the output of your bsoz, you will be down -3db at 18Hz. You need at least 100uF, then you will be down -3db at 1.5 Hz.
If this is the case you still havenīt got the full potential from the xsoz. I have been there. |
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| gnomus |
| It's a waste to to build a 20w SOZ or XSOZ. The most you should go for is 12 watts. Beyond that all you get is a lot more heat but all most no increase in volume at your speaker. |
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| moe29 |
Henrik,
Thanks for bringing that up again. I will make the modification and
report back. Maybe my initial listening impressions were biased
because it's something i built? ;) Is there a specific capacitor you
are using for that part? Thanks again for all your hard work in
this area!
Paul,
You are right - there is a steep curve of diminishing returns when
you are dealing with the SOZ and output power. It's easy to be
seduced by the power of the watt :devilr: |
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| Henrik |
Moe29
I am using Black Gate type N at 47uF at 50V, but they need to bracke in for many hours.
But Panasonic FC with an say 1uF coupling cap should be nice too.
And then X it.
I would like to read about your expierience.
Henrik. |
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| tomchaoda |
| quote: | The gain at the original BSOZ an SOZ was controlled by R115 and R207, now it is by R120, R121, R122, R123, and R212, R213, R214, R215, all resistors in the X-feedbackloop.
I have kept the original gainlevel, and also this gave the best frequency responce.
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Henrik:
I know the formula for original bosoz's gain is 20*log(R1+R2/R15). Is the gain for x-bosoz's gain calculated in this way:
gain=20*log[R1+R2/(R120+R121)//(R122+R123)] ?
Thanks,
Thomas |
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| Adams_Leo |
Hi Henrik,
I have built soz and want to upgrade to your version xsoz and xbosoz with CCS 03 which you have posted in this thread page 18.
Here I have one question,My current SOZ work voltage at +-25V,but you post sch show 19V.Do I need change some components value to match at +-25V.
http://www.diyaudio.com/forums/show...5&pagenumber=10
Thanks
Leo |
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