Keantoken's CFP cap multiplier - Page 116

prasi · 25th April 2020, 07:23 PM

thanks keen,
tried with a 500 ohm load, still same thing. grounding arrangement can be seen in the below image.
clean ground (317/337 and CMX share a common ground point near the leds.
rectifier and bulk caps are far upstream.

I will try replacing the 337/327 and see..
my load demand is quite low, ESP HPA. In that case will mje15033/32 pair be ok?
regards
prasi

keantoken · 25th April 2020, 07:36 PM

That layout looks okay. I notice I didn't recommend the 15033/32 for the Kmultipliers. That is likely because I didn't have any to test, or if I did, they were not stable.

I would suggest finding a way to load the kmultipliers over 25mA, or switching to D44/45H11G. You can also try switching to BC5xxC for the TO92s, that has also worked before.

Just to make sure it is not another problem, please give me the voltage at each transistor pin.

keantoken · 25th April 2020, 07:58 PM

For everyone else: I do have Kmultiplier boards, but I got them from the fab without being cut apart, and I can't find my shears. Until I do, you'll have to get 4 at a time and cut them apart yourself.

prasi · 25th April 2020, 10:09 PM

Quote:

Originally Posted by keantoken

That layout looks okay. I notice I didn't recommend the 15033/32 for the Kmultipliers. That is likely because I didn't have any to test, or if I did, they were not stable.

I would suggest finding a way to load the kmultipliers over 25mA, or switching to D44/45H11G. You can also try switching to BC5xxC for the TO92s, that has also worked before.

Just to make sure it is not another problem, please give me the voltage at each transistor pin.

Thanks kean, I will put them to good use in next project with recommended transistors ( an AKSA class A HPA) . meanwhile for this esp hpa , i built up a simple crc+lm317/337 as per Power Supply for Preamps , works fine for the purpose.

regards
prasi

proid · 1st July 2020, 03:03 AM

Hi Keantoken, i want to use some sot223 transistor for space saving so can i use bcp53/56, pzta06/pzta56 in place of big transistor?

keantoken · 1st July 2020, 04:06 PM

As long as the transistor can support the power dissipated, it is worth a try. If the transistor is not suitable you will have low PSRR or it may oscillate.

donovas · 17th July 2020, 01:54 PM

Prasi i was about to something very similar for my hp amp. I believe the original configuration was found in old parasound psu by john curl? My question is tho, since 317/337's max current output is 1.5a, does that influence the k multiplier's performance on where its current limit is set?

donovas · 23rd July 2020, 06:29 PM

Keantoken, im debating on whether to use this or the typical darlington cmx for my class a headphone amp. Reading up on pros and cons of cfp vs darlington it seems to me that cfp is harder to stabilize vs darlington having more 2h, at least in the output stage. But also i remember seeing that the transistor characteristic of an active psu will show up on the load. Then since darlington has more 2h, can we assume that as a cmx the same characterstic will be heard on the final sound?

25th April 2020, 07:36 PM	#1152
keantoken diyAudio Member Join Date: Aug 2006 Location: Texas	That layout looks okay. I notice I didn't recommend the 15033/32 for the Kmultipliers. That is likely because I didn't have any to test, or if I did, they were not stable. I would suggest finding a way to load the kmultipliers over 25mA, or switching to D44/45H11G. You can also try switching to BC5xxC for the TO92s, that has also worked before. Just to make sure it is not another problem, please give me the voltage at each transistor pin. __________________ The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer! Need something built, repaired or modded? PM me and ask what I can do!

25th April 2020, 07:58 PM	#1153
keantoken diyAudio Member Join Date: Aug 2006 Location: Texas	For everyone else: I do have Kmultiplier boards, but I got them from the fab without being cut apart, and I can't find my shears. Until I do, you'll have to get 4 at a time and cut them apart yourself. __________________ The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer! Need something built, repaired or modded? PM me and ask what I can do!

1st July 2020, 04:06 PM	#1156
keantoken diyAudio Member Join Date: Aug 2006 Location: Texas	As long as the transistor can support the power dissipated, it is worth a try. If the transistor is not suitable you will have low PSRR or it may oscillate. __________________ The Kmultiplier rail filter! -=- The Simple Kuartlotron Superbuffer! Need something built, repaired or modded? PM me and ask what I can do!

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1st July 2020, 03:03 AM	#1155
proid diyAudio Member Join Date: Sep 2011	Hi Keantoken, i want to use some sot223 transistor for space saving so can i use bcp53/56, pzta06/pzta56 in place of big transistor?

17th July 2020, 01:54 PM	#1157
donovas diyAudio Member Join Date: Jun 2014	Prasi i was about to something very similar for my hp amp. I believe the original configuration was found in old parasound psu by john curl? My question is tho, since 317/337's max current output is 1.5a, does that influence the k multiplier's performance on where its current limit is set?

23rd July 2020, 06:29 PM	#1158
donovas diyAudio Member Join Date: Jun 2014	Keantoken, im debating on whether to use this or the typical darlington cmx for my class a headphone amp. Reading up on pros and cons of cfp vs darlington it seems to me that cfp is harder to stabilize vs darlington having more 2h, at least in the output stage. But also i remember seeing that the transistor characteristic of an active psu will show up on the load. Then since darlington has more 2h, can we assume that as a cmx the same characterstic will be heard on the final sound?