Os,
Nice builds
With 3 pair mt200 what would be the ideal transformer VA size and capacitor bank needed for the 250W?
Nice builds
With 3 pair mt200 what would be the ideal transformer VA size and capacitor bank needed for the 250W?
I'm running my 3 -pair MT-200 on 40Kuf total / with a 400VA ( +/- 65V rails.)
5 pair X 2 on 82Kuf total with a 1KVA (+/- 72V rails).
All 3 amps never are stressed or strained in the least. 🙂
OS
If ultimate power handling isn't the goal wouldn't
2SA1215/2SC2921 be preferred to 2SA1295/2SC3264 for the better FT and Cob ?
-TJ
2SA1215/2SC2921 be preferred to 2SA1295/2SC3264 for the better FT and Cob ?
-TJ
With our huge driver stage , the Cob is no problem and Ft >30mhz is our
target. Might be cheaper just to use NJW ON's.
But the MT-200 package will give better SOA just by it's greater
thermal conductivity.
ANY of them will work , I've had 4 different output stages with 4
types , no difference ?
Driver specs are more important.
OS
IC thanks OS,
I think I've seen the 2SA1186/2SC2837 recommended for driver stage along with KSA1381/KSC3503 for predriver / VAS. Is this the current ideal at this moment in your mind or are there other parts which might suite just a little smidgen better.
-TJ
I think I've seen the 2SA1186/2SC2837 recommended for driver stage along with KSA1381/KSC3503 for predriver / VAS. Is this the current ideal at this moment in your mind or are there other parts which might suite just a little smidgen better.
-TJ
I use 1381/3503 - 2sa1294/2sc3263 - njw0281/0302 , I can hook 90V rails
to the thing.
While the 2SA1186/2SC2837 have better specs , you would be limited to
<70V rails.
In real world performance - no difference. Simulation shows that
using a high Ft- lower Cob driver pair can allow the OPS to circumvent
it's 300V/us "speed limit". kypton ND and the failed "infidel" plotted
at 350+ and 500V/us with toshiba drivers. 300V is the limit with
my setup above.
Isn't 300V/us enough ?? That's quite speedy ....
OS
I don't know exactly what you have available there.
It should to be a to-126 (to fit). ECB pinout. A to-92L / to-92
can also be used. Make sure of pinout.
- High Vceo > 250V , lower Cob < 30pf , High Ft >60mhz.
-don't use mje340/350 for Q105/106 , Q101-104 , 340/350 are OK .
Hope this helps. You might have to read a few spec sheets , feel free
to run any choices by me ....
OS
D102 = any red led with Vf 1.6-1.8V. In circuit , it passes about
80% of the input stages Ivas. Most reds are rated >20ma.
OS
For alternate transistors you can use KSA1220A / KSC2690A pairs in the Y gain group. They are 160V devices, so you have a limit on your power supply voltage but otherwise they are nice devices.
I tried 1381,3503 as pre drivers(Q105/106) in an early test without any compensation in drivers(Q107/108,2sc4793-2sa1837) , i hasn't seen any instability.
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Problem with Farchild in my country is Mouser...they charged 40 EUR for shipping😱😱
....so I found like replacement BF471/BF472
....so I found like replacement BF471/BF472Mouser send free shipping on orders over 65euro here in Greece.Problem with Farchild in my country is Mouser...they charged 40 EUR for shipping😱😱
For those who will need devices I have ordered the following for myself from a reputable supplier. I will have extras. Price is TBD but will be very close to major supplier price.
2sa1381E and F
2sc3503E and F
ksa1220AYS
ksc2690AYS
bd13916STU
njw0281G
njw0302G
2sa1381E and F
2sc3503E and F
ksa1220AYS
ksc2690AYS
bd13916STU
njw0281G
njw0302G
Question on what exactly to build for the following speakers ->
http://www.mrhifi.fi/pdf/tannoy/Dimension.pdf
I've got the TD8 and TDC1. Max rated peak power for TD8 is 375 watts and for TDC1 is 480 watts.
both can be biamped which I'm looking to do, I can wait on OS for the tweaked Kypton-ND all in one for high frequency but what to use for LF. I've got 2 x 1200 watt 18" Subs as well.
Suggestions on IPS and Power to use for the slews ?
-TJ
http://www.mrhifi.fi/pdf/tannoy/Dimension.pdf
I've got the TD8 and TDC1. Max rated peak power for TD8 is 375 watts and for TDC1 is 480 watts.
both can be biamped which I'm looking to do, I can wait on OS for the tweaked Kypton-ND all in one for high frequency but what to use for LF. I've got 2 x 1200 watt 18" Subs as well.
Suggestions on IPS and Power to use for the slews ?
-TJ
Maxwell,
I would take Evan's offer of the extra devices he has ordered and the cost of sending them to you by mail will more than make up for the distance from the US to your country. Many here would gladly order your parts locally with their own orders and send you the parts, if they are in a small letter sized package they should not get caught up in any customs checkpoints. You really are looking at small parts.
I would take Evan's offer of the extra devices he has ordered and the cost of sending them to you by mail will more than make up for the distance from the US to your country. Many here would gladly order your parts locally with their own orders and send you the parts, if they are in a small letter sized package they should not get caught up in any customs checkpoints. You really are looking at small parts.