Banned
Joined 2002
Jason...........
It is supposed to be IRFP240!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Not IRFP250.............. The 250 has almost double the input capacitance... yuckie
I sent you 150 resistors, just as as you asked. When you total the orders up let me know how many extra you need. Also, let me know when those arrive. I'm not going to send extras out if these don't make it. I'd rather mail them direct to the buyers in that case. Brian might also be able to mail them with the boards.
Mark
It is supposed to be IRFP240!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Not IRFP250.............. The 250 has almost double the input capacitance... yuckie
I sent you 150 resistors, just as as you asked. When you total the orders up let me know how many extra you need. Also, let me know when those arrive. I'm not going to send extras out if these don't make it. I'd rather mail them direct to the buyers in that case. Brian might also be able to mail them with the boards.
Mark
Banned
Joined 2002
Peter Daniel said:
The 140 has a lower resistance and capcitance according the IRF site. I am currently using IRF140N devices, the voltage rating is lower, but the current capacity is very high.
Maybe this spreadsheet I made will help, prices are probably out of date but specs are the same.
Anthony
pinkmouse said:I always thought if you ordered more, it got cheaper!
jleaman said:
WorkingAtHome said:
Future-Active has the lowest prices in Canada, I believe.
Here is a sample quote from thier website, I got today.
Part#
[Mfr] Customer Part# Description Pkg Qty Stock Unit Price Qty Amount
IRFP240
INTERNATIONAL RECTIFIER CORP MOSFET TO247 NPD 200V .18RDS
425 In Stock 1.1385
$483.86
IRFP250N
INTERNATIONAL RECTIFIER CORP 200V 30A TO247 ***/SELL IR218X
425 In Stock 1.1385
$483.86
BTW, I have been working as a Global Sourcing Manager for Electronic Components for the last 6 years. If you need help sourcing parts you could do worse than ask me for help.
Regards
Anthony
Ok, i'm gonna throw my 2 cents in here really quickly, and someone correct me if i'm wrong...please. I don't think it much matters what FETs you use because odds are that you aren't going over the current or voltage limits of any of them. What i mean by any of them is
irfp044, irfp140, irfp240, irfp250n.
for these small alephs as long as you don't use high voltage, irfp044 would probably be great since it has such a high current capacitry. that said, the amount of current you will be running through them will be minimal compared to their ratings (i think irfp044 is like 60v and 70A!) irfp240 is 200v and 20A? either way, for these amps you only want to run between 25 watts and maybe maybe 50 watts dissipation per fet. Yes, irfp250n's do have more capacitance like Mark says. Its basically two irfp240's parallel in one chip, but without any more surface area to dissipate any more heat, so, more capacitance, more current capability, same surface area.
On the other hand, i cannot speaker to sonic signatures of these FETS. I used irfp240's in my aleph 2's and they sound right nice, but i didn't try the 044s or the 250n's that i have. Maybe Peter can comment better on sonic signature.
nows about the time where i duck and run for cover hehe
-Matthew K. Olson
irfp044, irfp140, irfp240, irfp250n.
for these small alephs as long as you don't use high voltage, irfp044 would probably be great since it has such a high current capacitry. that said, the amount of current you will be running through them will be minimal compared to their ratings (i think irfp044 is like 60v and 70A!) irfp240 is 200v and 20A? either way, for these amps you only want to run between 25 watts and maybe maybe 50 watts dissipation per fet. Yes, irfp250n's do have more capacitance like Mark says. Its basically two irfp240's parallel in one chip, but without any more surface area to dissipate any more heat, so, more capacitance, more current capability, same surface area.
On the other hand, i cannot speaker to sonic signatures of these FETS. I used irfp240's in my aleph 2's and they sound right nice, but i didn't try the 044s or the 250n's that i have. Maybe Peter can comment better on sonic signature.
nows about the time where i duck and run for cover hehe
-Matthew K. Olson
Banned
Joined 2002
Coulomb said:
Future-Active has the lowest prices in Canada, I believe.
Here is a sample quote from thier website, I got today.
Part#
[Mfr] Customer Part# Description Pkg Qty Stock Unit Price Qty Amount
IRFP240
INTERNATIONAL RECTIFIER CORP MOSFET TO247 NPD 200V .18RDS
425 In Stock 1.1385
$483.86
IRFP250N
INTERNATIONAL RECTIFIER CORP 200V 30A TO247 ***/SELL IR218X
425 In Stock 1.1385
$483.86
BTW, I have been working as a Global Sourcing Manager for Electronic Components for the last 6 years. If you need help sourcing parts you could do worse than ask me for help.
Regards
Anthony
We need to talk email me or call me im at home you have my ##
J'
I can't say on the 140 but the 044 seems to have more rolled off high end, or softer so to say. I think the 044 also has alot higher input capacitance than the 240. Won't those devices with a higher input capacitance require more drive current as well? In the Alephs there is not very much drive corrent available in the first palce...... At any rate I've had the best luck with 240's and lower capacitance gates, start stacking the devices such as three or more per rail or and it gets higher yet! Too much input capacitance is not a good thing by my ears.
Mark
Mark A. Gulbrandsen said:
I built an A30 with IRFP044's and it does seem softer than
my previous amp. That said, I don't think I'll be in hurry to
replace the mosfets.
I remember from the Zen articles that the 044' has lower
distortion and higher transconductance than the 140s and 240
devices. It also has a higher wattage rating. So perhaps
the 044 is best used in small numbers, lower voltages
and higher current.
Dennis
Banned
Joined 2002
Hi,
At the moment I have ordered mini aleph component kits, I was just wondering how many components are different for the a30 kits?
I definatley want to try the mini a config first, and then perhaps experiment with the extra ouput devices.
So If I were to pay the extra and 'upgrade' to the a30 components, would I be able use some of the components from the a30 kit to run mini a version fisrt, and then add the remainder for a30 if I wished to do so?
Basically speaking does the aleph 30 kit have the components required to operate the 10w version????
Thanks
Raja
At the moment I have ordered mini aleph component kits, I was just wondering how many components are different for the a30 kits?
I definatley want to try the mini a config first, and then perhaps experiment with the extra ouput devices.
So If I were to pay the extra and 'upgrade' to the a30 components, would I be able use some of the components from the a30 kit to run mini a version fisrt, and then add the remainder for a30 if I wished to do so?
Basically speaking does the aleph 30 kit have the components required to operate the 10w version????
Thanks
Raja
It was the IRFP240 from the beginning of this post and I think that we should stay with it because it was used in many many amps before. If someone wants to experiment in there own amp, good for them. Do it, and share your comment on this forum. But for the present project, lets keep the IRFP240. We all know that it had always made the job right.
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