Member
Joined 2002
no nelson that is not a good rule you want to wait till it starts smokin first because some time the woofer will come out on its own and escape from the frame. LMAO hehe : O ) this place RULES
Have any of you tried to raise the idle current in the irf9610 diff-pair to .. 100mA?
I know it is high and you have the lower r16 and r17 to 39ohm, but in the end the one of the dominant pole of the circuit will move up >> lower phase shift in the treble...
Also then you need some cooling of the irf9610's.
I will maybe start build one too. ... but this will in the end of oktober.
Sonny
I know it is high and you have the lower r16 and r17 to 39ohm, but in the end the one of the dominant pole of the circuit will move up >> lower phase shift in the treble...
Also then you need some cooling of the irf9610's.
I will maybe start build one too. ... but this will in the end of oktober.
Sonny
of course we are here talking about soundstage. Does the raise in current change the soundstage in posetive or negative direction.
Well, wire in a temporary circuit on a 4 pole switch and try it out. Just remember to turn the power off first or you will get a hell of a thump. Then tell us what you think happens to the soundstage.
Anthony
Anthony
Nelson Pass said:
Hi, Nelson,
I guess the preferred parts referring to IRFP240. Why do prefer IRFP240 over IRF244?
I don't prefer the IRFP240 (plastic) over the
IRF244 (TO-3). As I believe I mentioned, the
TO-3 version of the IRF240 comes with non-standard
pin thickness, but the IRF244 has standard pins.
In either case, IR seems to have ceased production
of the TO-3 versions, and the plastics are what most
people will be living with.
IRF244 (TO-3). As I believe I mentioned, the
TO-3 version of the IRF240 comes with non-standard
pin thickness, but the IRF244 has standard pins.
In either case, IR seems to have ceased production
of the TO-3 versions, and the plastics are what most
people will be living with.
It seems a shame to let this thread poop out before
100,000 views, so I guess I'll just have to come up with
something this weekend to give it some life.
100,000 views, so I guess I'll just have to come up with
something this weekend to give it some life.
I'll just have to come up with
More pictures! This time of the Naughty Bits. Know what I mean...wink wink, nudge nudge.
Art
P.S. What's it like?
More pictures! This time of the Naughty Bits. Know what I mean...wink wink, nudge nudge.
Art
P.S. What's it like?
OK, I didn't come up with anything over the weekend, but
I do remember a little tidbit:
The XA200 turned out not to need the compensation
capacitor on the NPN transistor controllling the current
source, nor does it need a lag capacitor on the N channel
gain devices. The remaining compensation cap, 5 pF in
parallel with the feedback loop resistor, is being eliminated
with a board layout revision.
(By contrast, I count 10 compensation caps in the schematic
of the Halcro, and something approximating 30 in each
channel of the ML No. 333)
😎
I do remember a little tidbit:
The XA200 turned out not to need the compensation
capacitor on the NPN transistor controllling the current
source, nor does it need a lag capacitor on the N channel
gain devices. The remaining compensation cap, 5 pF in
parallel with the feedback loop resistor, is being eliminated
with a board layout revision.
(By contrast, I count 10 compensation caps in the schematic
of the Halcro, and something approximating 30 in each
channel of the ML No. 333)
😎
There's plenty of stuff to go on about. How about are there any folks out there who've used, say, Motorola MOSFETs instead of the IR for their Alephs, Zens and X's.
We can never see to many pictures of Peter's workmanship.
Or too much of Nelson's for that matter either.
We can never see to many pictures of Peter's workmanship.
Or too much of Nelson's for that matter either.
Nelson Pass said:It seems a shame to let this thread poop out before
100,000 views, so I guess I'll just have to come up with
something this weekend to give it some life.
Nelson,
I was looking at the XA 200 pictures, again, and again I couldn't find the first cap in the CRCRC sequence. All I can see is an RCRC, with C being 15,16 17,18,19,20,21,22.
Not the it matters really but...am I wrong?
I was looking at the XA 200 pictures, again, and again I couldn't find the first cap in the CRCRC sequence. All I can see is an RCRC, with C being 15,16 17,18,19,20,21,22.
Not the it matters really but...am I wrong?
There are 6 PC mount capacitors on the board on the
bottom read which also hold the high speed / soft
recovery diodes for the bridge.
This is subject to revision, however.
Yes, we finally bit the bullet on the fancy diodes.
😎
bottom read which also hold the high speed / soft
recovery diodes for the bridge.
This is subject to revision, however.
Yes, we finally bit the bullet on the fancy diodes.
😎
And all this time, I was wondering what I was doing wrong that my prototype circuit was stable without that confounded cap on the NPN.
I'm shocked...shocked, I say. Clearly a communist plot to test my sanity!
(It worked. I went over the edge.)
As I understand it, that leaves Nelson's version of the circuit (i.e. the 'real' one) with only a DC blocking cap on the input. I'm brave and/or foolish. I don't use one (two, actually) there.
No, I didn't try the circuit without the compensation cap on the feedback loop. I'll give it a shot.
Grey
I'm shocked...shocked, I say. Clearly a communist plot to test my sanity!
(It worked. I went over the edge.)
As I understand it, that leaves Nelson's version of the circuit (i.e. the 'real' one) with only a DC blocking cap on the input. I'm brave and/or foolish. I don't use one (two, actually) there.
No, I didn't try the circuit without the compensation cap on the feedback loop. I'll give it a shot.
Grey
I'm not afraid of the DC input, but there are simply too
many complaints in the field when we don't have them.
For low offset, the circuits wants to see similar DC
source impedances on both + and - inputs.
The fearless customer with a soldering iron is, of course,
welcome to bypass them.
many complaints in the field when we don't have them.
For low offset, the circuits wants to see similar DC
source impedances on both + and - inputs.
The fearless customer with a soldering iron is, of course,
welcome to bypass them.
My Aleph 5 is using none of the compensation caps nor the feedback cap. It seems to be OK. Some people even commented on some special magic it produces.😉