Re: IRFP240 Substitute
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The Ic rating is generally much higher (even derated) than is necessary here. The Rdson is also an unimportant spec. for this type of use. Probably, other than breakdown voltage, the capacitances and their characteristics(how linear the curve is) below 30V are most important. Transconductance in the same range would be good.themystical said:Can somebody confirm whether IRFP250 can be substituted for the IRFP240 in this application. The IRFP250 appears to have a higher current rating but lower rDS (ON) for the same rated voltage.
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Hit two birds with one stone!
I am using ZV9 to feed my Visaton B200 in the Open baffle. Since Visaton is now high-passed at around 300 Hz, (first-order)...I just have to remove that big ugly elco at the output, and leave only one small good cap... 😎
I am using ZV9 to feed my Visaton B200 in the Open baffle. Since Visaton is now high-passed at around 300 Hz, (first-order)...I just have to remove that big ugly elco at the output, and leave only one small good cap... 😎
ak4396 said:Nice!!!
I will do so�
Correct me if I’m wrong.
In my opinion polarity should by reversed:
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sts9 said:
Correct me if Im wrong.
In my opinion polarity should by reversed:
comparing to what ?
Papa drew that "-" on output of amp - to preserve absolute polarity .
connect spks as you wish , but all in same manner .
Vix said:Hit two birds with one stone!
I am using ZV9 to feed my Visaton B200 in the Open baffle. Since Visaton is now high-passed at around 300 Hz, (first-order)...I just have to remove that big ugly elco at the output, and leave only one small good cap... 😎
Let me know what caps you use. this is a XO point I want to try as well in OB.
😀
OT
Are you using T-Bass? would like to know what you think of that endevour.
Re: IRFP240 Substitute
Yes, but I suggest that you use fewer of them.
😎
Whoops, thought this was an Aleph 3. Yes the 250 will be fine.
themystical said:Can somebody confirm whether IRFP250 can be substituted for the IRFP240 in this application. The IRFP250 appears to have a higher current rating but lower rDS (ON) for the same rated voltage.
Yes, but I suggest that you use fewer of them.
😎
Whoops, thought this was an Aleph 3. Yes the 250 will be fine.
Re: Re: IRFP240 Substitute
Can I sub the ZTX450 for a BC546c? I have plenty of those, I will just reverse it's position.
Looks like the ZTX has more guts, but not sure if it's needed.
Mike T(ea Bag)
Nelson Pass said:
Yes, but I suggest that you use fewer of them.
😎
Whoops, thought this was an Aleph 3. Yes the 250 will be fine.
Can I sub the ZTX450 for a BC546c? I have plenty of those, I will just reverse it's position.
Looks like the ZTX has more guts, but not sure if it's needed.
Mike T(ea Bag)
Re: Re: Re: IRFP240 Substitute

Tea-Bag said:
Can I sub the ZTX450 for a BC546c? I have plenty of those, I will just reverse it's position.
....

Just in case you would think it is too many 1000uF's to fit, here are some 3300uF Silmic's:
http://cgi.ebay.com.hk/ws/eBayISAPI...tegory=4662&tc=photo&_trksid=p1742.m153.l1262
Dont forget good supply cap's for the ZenV9😉
🙂
http://cgi.ebay.com.hk/ws/eBayISAPI...tegory=4662&tc=photo&_trksid=p1742.m153.l1262
Dont forget good supply cap's for the ZenV9😉
🙂
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These 3300uF caps maybe fake.
According to the latest (2009) Elna catalogue. Elna do not make 3300uF with a 50V rating.
I will email Elna to confirm either way.
According to the latest (2009) Elna catalogue. Elna do not make 3300uF with a 50V rating.
I will email Elna to confirm either way.
I just want to get peoples opinions on power supply caps.
On the official F3 service manual Nelson specifies 25V 15000uF caps. However the amp requires a 46V power supply.
So I would have thought 25V caps would not be adequate for this amp.
Has Nelson made a mistake?
Since Class A amps draw constant current, then would using Epcos Sikorels make much of difference compared to Panasonc TSHA?
I suspect they would make a greater difference for a Class A/B amp, where the current draw is always changing.
Anyway some opinions on this would be appreciated, espescially Peter since he has actually used Sikorels before.
Will 30,000uF caps be a good match for this amp?
On the official F3 service manual Nelson specifies 25V 15000uF caps. However the amp requires a 46V power supply.
So I would have thought 25V caps would not be adequate for this amp.
Has Nelson made a mistake?
Since Class A amps draw constant current, then would using Epcos Sikorels make much of difference compared to Panasonc TSHA?
I suspect they would make a greater difference for a Class A/B amp, where the current draw is always changing.
Anyway some opinions on this would be appreciated, espescially Peter since he has actually used Sikorels before.
Will 30,000uF caps be a good match for this amp?
thanh1973 said:Has Nelson made a mistake?
It would not be the first time, but I have a large quantity of 25V
caps, so I ran them in series from what would have normally been
a split supply. I made up for it with a big fat capacitor multiplier
on the supply.
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Need help finding C8 film cap for PD PCB
I recently purchased the F3 boards from Peter Daniel and I am working on my BOM to make sure that I select components of the proper size and lead spacing. I am challenged to find a 1uF film cap (MKP-metallized Polypropylene type) that will properly fit into this spot with a 5mm lead spacing. I would like to stay with Digi-Key or Mouser.
Also, has anyone tried something like a Nichicon KG Gold Tune cap for C1? I am considering a 10,000uF/63V electrolytic for this.
Appreciate any suggestions.
I recently purchased the F3 boards from Peter Daniel and I am working on my BOM to make sure that I select components of the proper size and lead spacing. I am challenged to find a 1uF film cap (MKP-metallized Polypropylene type) that will properly fit into this spot with a 5mm lead spacing. I would like to stay with Digi-Key or Mouser.
Also, has anyone tried something like a Nichicon KG Gold Tune cap for C1? I am considering a 10,000uF/63V electrolytic for this.
Appreciate any suggestions.
Re: Need help finding C8 film cap for PD PCB
The smaller 1 uF/50 or 63 V MKP "box type" caps have 15 mm lead spacing. BC (Philips) grey MKPs are available at Digikey. I think this the same cap used by NP in his Aleph J front end (- input of the differential stage) according to the internal pictures I saw.
If you need a smaller cap, you must choose an MKT or find a suitable axial component, but these are generally bigger as they are at least 160 V
The German ERO (Roederstein) used to make some nice axial MKPs (1845 series, blue color). You might find some good NOS ERO caps on eBay with a bit of luck.
Peter might help you in choosing the right one anyway.
P.S. Film&Foil caps are generally better than MKP, but much bigger and expensive, such as Mundorf Supreme series
The British ClarityCaps are claimed to be very good too, but, again, very big.
rhing said:I am challenged to find a 1uF film cap (MKP-metallized Polypropylene type) that will properly fit into this spot with a 5mm lead spacing. I would like to stay with Digi-Key or Mouser.
The smaller 1 uF/50 or 63 V MKP "box type" caps have 15 mm lead spacing. BC (Philips) grey MKPs are available at Digikey. I think this the same cap used by NP in his Aleph J front end (- input of the differential stage) according to the internal pictures I saw.
If you need a smaller cap, you must choose an MKT or find a suitable axial component, but these are generally bigger as they are at least 160 V
The German ERO (Roederstein) used to make some nice axial MKPs (1845 series, blue color). You might find some good NOS ERO caps on eBay with a bit of luck.
Peter might help you in choosing the right one anyway.
P.S. Film&Foil caps are generally better than MKP, but much bigger and expensive, such as Mundorf Supreme series
The British ClarityCaps are claimed to be very good too, but, again, very big.
Thanks for the response Massimo. As you mentioned, the MKP box caps have larger lead spacings than what Peter Daniel's PCB can accommodate. I did find this Wima MKS 2 cap at Mouser that should fit, although I am not familiar with what the possible sonic signature of the MKS 2 caps might be. If anyone else has suggestions, please let me know. I'd like to get going on building this.
Those are metallised polyester caps, like MKT.
But I understand, space is tight. Go for them, they are good quality caps and they don't cost a fortune. In the future you might find something better and you didn't waste too much money.
(No idea about the sound, anyway)
But I understand, space is tight. Go for them, they are good quality caps and they don't cost a fortune. In the future you might find something better and you didn't waste too much money.
(No idea about the sound, anyway)
Hi Helson
I noticed on the schematic thre are quite a few 220uF capacitors.
I have a stack of 470uF capacitors.
Is there any problem using these 470uF caps in place of the 220uF caps shown on the schematic?
What effect will this have?
I noticed on the schematic thre are quite a few 220uF capacitors.
I have a stack of 470uF capacitors.
Is there any problem using these 470uF caps in place of the 220uF caps shown on the schematic?
What effect will this have?
Well to partly answer my own question.
I think that using 470uF at C5, C6, C7, C10 won't have a negative effect.
However C2, C3, C4, I am not too sure about.
I think that using 470uF at C5, C6, C7, C10 won't have a negative effect.
However C2, C3, C4, I am not too sure about.
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