My brotherinlaw is a fat black boy, used to be an enormous Q-fan despite moi informing him about the true nature of hairy Freddy.
He never touched the albums again after it became fact when Mr Mercury vaporised.
Ah, the good old Reed/Bowie/Pop heroic days, much more interesting.
Fruit-oftheLoom
He never touched the albums again after it became fact when Mr Mercury vaporised.

Ah, the good old Reed/Bowie/Pop heroic days, much more interesting.
Fruit-oftheLoom
What a shame for your bro-in-law. Music should be enjoyed on it's own merits irrespective of the proclivities of the performer.
Even to this day, the colored society is pretty conservative.
Personally, i prefer 'm contraversial and undefined. (hence +35 years of Zappa admiration)
Personally, i prefer 'm contraversial and undefined. (hence +35 years of Zappa admiration)
blown fuse
Hi guys,
i've just blown the fuse (2A slow) on the primary trafo windings.
I can swear that the amp is ok (i tested with a separate psu a few days ago). I used only one thermistor from star ground to chassis, not the one on the primary (because i've got a single primary not dual) nor the re-phasing line cap (.0033).
Do you think is the inrush current the cause of the blown fuse or there must be something wrong with my amp?
Many thanks in advance 🙂
Marco
Hi guys,
i've just blown the fuse (2A slow) on the primary trafo windings.
I can swear that the amp is ok (i tested with a separate psu a few days ago). I used only one thermistor from star ground to chassis, not the one on the primary (because i've got a single primary not dual) nor the re-phasing line cap (.0033).
Do you think is the inrush current the cause of the blown fuse or there must be something wrong with my amp?
Many thanks in advance 🙂
Marco
Babowana said:
More bass . . . ?
What about the quality?
I also driving F4 with a tube pre (20dB).
I'm really satisfied with the bass quality.
(I don't have ZV9 to compare, tho . . .)
![]()
Read post 1984. I was just wondering if anyone else was hearing the same thing. The F4 has great detail and sounds nice.

MikeW said:Ok, I added a 25,000 uf cap from the plus to minus supplies. A little better.![]()
First time I hear something like this

Experimentation leads to unexpected results 😀
hershann said:
So that means - after the 2 bridge rectifiers I split the wires to supply 2 PS boards, each supplying a F4 board (i.e. parallel supply)
thanks
her shann
Peter Daniel said:Yes.
Just thought about it -
I am going to use a 400VA 18v-0-18v transformer. Assuming I use the 33,000uF x 4 per PS board x 2 board = 264,000uF total. This is going to be significantly higher than the 120,000uF in the original design.
How big / long will the in-rush current be? Will the single CL60 thermistor be enough to reduce it? How do you calculate the in rush current and what's the usual safety rating (depends on how hot the transformer get?). Or will the 1.5A slow blo fuse (240V wall power) go first?
Lots of questions from a newbie... ...
her shann
Einstein said, "Everything should be made as simple as possible, but no simpler."
As to the filter caps I would say: "Use as little as possible, but not too little."
Using too much capacitance can sometimes be harmful to the sound.😉
I used 2 x 15,000uF per channel in my Zv9 and I don't feel like a need more.
As to the filter caps I would say: "Use as little as possible, but not too little."
Using too much capacitance can sometimes be harmful to the sound.😉
I used 2 x 15,000uF per channel in my Zv9 and I don't feel like a need more.
Peter Daniel said:Einstein said, "Everything should be made as simple as possible, but no simpler."
As to the filter caps I would say: "Use as little as possible, but not too little."
Using too much capacitance can sometimes be harmful to the sound.😉
I used 2 x 15,000uF per channel in my Zv9 and I don't feel like a need more.
Agreed - looks like I'll just use 1 PS board to keep everything simple then.
her shann
apassgear said:
First time I hear something like this
![]()
Experimentation leads to unexpected results 😀
http://www.passlabs.com/np/MPA_PS_D0.pdf
They look like they go plus to minus rails to me.
😀
hershann said:Will the single CL60 thermistor be enough to reduce it?
If you are in doubt, try to use two of them: one at one entrance
of the primary and another one at the other entrance.

hershann said:Will the single CL60 thermistor be enough to reduce it?
You may also consider CL70 which offers more resistance initially.
jacco vermeulen said:ever thought of regional general preferences ?
It depends even in our region.
Young people rush to disco club or rock café for girl-hunting and boy-hunting, moving their well-built bodies sexy in all different directions under large size of noisy music. Power and full of bass should be there to hold on their peripheral nerves. Yeah, not only for this, but the full of bass has another effect which can kick out the old boys to the outside street.
At home, we try to listen to the music constructed on the right balance between each instrument and the music in the right harmonies of all instrumental roles. We want the correct basses in the right places.

Babowana said:
...Yeah, not only for this, but the full of bass has another effect which can kick out the old boys to the outside street.
At home, we try to listen to the music constructed on the right balance between each instrument and the music in the right harmonies of all instrumental roles. We want the correct basses in the right places.
![]()
Amen to that!
Well, not often, but sometimes I like to listen at home like that too😉
http://youtube.com/watch?v=ZNcYMLJuM5U&feature=related
http://youtube.com/watch?v=ZNcYMLJuM5U&feature=related
Peter Daniel said:Well, not often, but sometimes I like to listen at home like that too😉
http://youtube.com/watch?v=ZNcYMLJuM5U&feature=related
That equipment in the first segment moves about as slow as I do these days...😉 Oh, to be 25 again...😀
One world One sky We live We die . . .
And, busy machines ? ? ?
I want to live in the nature . . . outside factory . . . outside city . . .

And, busy machines ? ? ?
I want to live in the nature . . . outside factory . . . outside city . . .

Blitz said:Why is the current value 150R for the "grid stoppers" / Series resistors ?
I have run values from 50 up to 475 ohms. They obviously want
to be lower for more bandwidth, but at some point instability
creeps in. At higher values you start losing gain at high frequencies.
A good square wave is helpful in evaluating this - look at the
500 KHz to 1 MHz region for overshoot.
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