Of course if you read this entire thread carefully, you will find a post early
on that addresses the 2.4 ohm resistor and discusses why it appeared in that
early copy. Of course no one is expected to go back that far or remember
all this stuff, so take my word for it - that resistor was specific to trim that
channel in the same way P3 did in later production. If you don't have a
distortion analyzer to fine trim the 2nd harmonic, then faggedabadit.
Jacco, would be great if there were an F- directory listing out each strengths, makes it a lot easier then doing F-1,2 ,3,4,5,..
I'm sure you could do a great job here ........
And a note to those who have been waiting patiently, I'm about 10 days
from releasing the F5 Turbo Kraken.
864000 863999 863998 ....
I got it and the only ripercussion is that I am still using my old speakers
Gogle up Amplimo speaker protection relay and NTE7100
because the F5 balances from the moment there already is a little trickle of mains voltage, the output balances stable around +/- 10 mV (worst case maybe 50 mV), that is an incredible low voltage, not doing any harm.
In other words: you will hear no thump when turning it on.
Of course the current might differ from the first seconds to later, but that is thermionic stabilization, not influencing the DC output.
So . . . there is no need for a temporary delay to connect the speakers. A relay just obvurbiates the straight connection of wire in wire out.
albert
In other words: you will hear no thump when turning it on.
Of course the current might differ from the first seconds to later, but that is thermionic stabilization, not influencing the DC output.
So . . . there is no need for a temporary delay to connect the speakers. A relay just obvurbiates
the straight connection of wire in wire out. albert
Ah, but i gathered the idea was that folks are/were doing this, half for understanding, and half for building.
P3 pot thd
After reading recent messages about P3, I tried this evening some tests on a couple of my F5 monoblocks (Vishay IRFP240-9240). I used a 1k 25turn pot. Very interesting results, about a factor of 10 in less thd after fine tuning with Arta 1.7.1 and M-Audio AP192 (see pdf if you like). Tomorrow I'll listen some music to hear the difference.
After reading recent messages about P3, I tried this evening some tests on a couple of my F5 monoblocks (Vishay IRFP240-9240). I used a 1k 25turn pot. Very interesting results, about a factor of 10 in less thd after fine tuning with Arta 1.7.1 and M-Audio AP192 (see pdf if you like). Tomorrow I'll listen some music to hear the difference.
Attachments
Speaker protection pass f5(dual output)
Is it nessacary. After going thru the forum far and wide,
So am I right in assuming that the speaker protection mechanisms we are not confident off.
I have never blown fuses on my B&K7270 I am using it for almost 7 years.
I feel it is less likely that speakers would get damaged because of stabilized(tested) amplifier.
Would like to run on Old speakers for a month later switch it back to New speakers. How does it sound.
I see that the original pass f5 from firstwatt.com has protection. Are these copyrighted.
Others can comment too.
Thanks
Pandu
Is it nessacary. After going thru the forum far and wide,
So am I right in assuming that the speaker protection mechanisms we are not confident off.
I have never blown fuses on my B&K7270 I am using it for almost 7 years.
I feel it is less likely that speakers would get damaged because of stabilized(tested) amplifier.
Would like to run on Old speakers for a month later switch it back to New speakers. How does it sound.
I see that the original pass f5 from firstwatt.com has protection. Are these copyrighted.
Others can comment too.
Thanks
Pandu
Regarding O/P protection -
My 'diy efforts' are occassionally suffer from mistakes, despite the much repeated checking/testing and as my speakers are the result of much time & effort, adding the extra relays in the signal path is an obvious choice and fortunately, I have not found any sound quality degradation, so far, even testing with the h/phones - other builders might differ, naturally.
[Besides, the P/S Rail C multipliers don't quite charge up together at the same rate so need to delay the load connection for a few minutes for this, and the bias, to settle down]
For the h/phones, I would still like to find a reliable circuit that drops out the relays with a dc offset of less than 100mV, if anyone knows of one .....
My 'diy efforts' are occassionally suffer from mistakes, despite the much repeated checking/testing and as my speakers are the result of much time & effort, adding the extra relays in the signal path is an obvious choice and fortunately, I have not found any sound quality degradation, so far, even testing with the h/phones - other builders might differ, naturally.
[Besides, the P/S Rail C multipliers don't quite charge up together at the same rate so need to delay the load connection for a few minutes for this, and the bias, to settle down]
For the h/phones, I would still like to find a reliable circuit that drops out the relays with a dc offset of less than 100mV, if anyone knows of one .....
And a note to those who have been waiting patiently, I'm about 10 days
from releasing the F5 Turbo Kraken.
the coming 10 days will not be easy start from this moment!
An externally hosted image should be here but it was not working when we last tested it.
10 days... seems like an eternity
100 mV shuld be plenty to charge up the capacitors
Just play about with the value of the resistors (56K?)
I am new at this and my math is baaaaaaad sorry if I can't help more.
Maybe if you use a dummy load and manage to ofset the amplifier you can get the right values by using a pot worked for me
The spec of the NTE give you the voltages needed to trigher the relay
