Carlos, you have 8 Ohms speakers. Don't you ?
Mine are 6 Ohms, and normally I test the amp with 4/2 Ohms speakers(this ones have 5 drivers but 98dB sensitivity).
Do you think 10,000uF per rail will work fine with this speakers?
Mine are 6 Ohms, and normally I test the amp with 4/2 Ohms speakers(this ones have 5 drivers but 98dB sensitivity).
Do you think 10,000uF per rail will work fine with this speakers?
metalman said:
carlosfm said:
The only reason I want to parallel before the X (SuSy) circuit is the speakers will be rather low impedance... between 2 and 3 ohm I think very likely. 😉 May dip below but I think I can keep it above 2. I also have a few of the LM3886 to mess with, and will likely wire up one with those before the LM4780's. There I can obviously go with this circuit as-is. Looking forward to it.
C
carlos, why dont you try a tracking pre-regulator version . It is a cheap way to get quite improved noise performance. since the pre regulator is referenced to the output of the main regulator. the main regulators input also benefits from the regulation of its output,. (and who knows maybe the snubberization as well 🙂 ) and the error amplifiers in those things need as much help as they can get, they are about the quality of a 741!
i hope that makes some kind of sense.
you need to have a bit more of a voltage drop though.
you just need another 338, a cap and 2 resistors per rail.
its on page 12 of here
http://www.national.com/ds/LM/LM138.pdf
i hope that makes some kind of sense.
you need to have a bit more of a voltage drop though.
you just need another 338, a cap and 2 resistors per rail.
its on page 12 of here
http://www.national.com/ds/LM/LM138.pdf
Try some LT1083s which have better HF impedance characteristics than the LM338 which are not as high performance. The snubber values will need to change I imagine. The LT1083 is unfortunately more expensive though.
Here's one example with no snubbers.
http://shine7.com/audio/gainclone.htm
Here's one example with no snubbers.
http://shine7.com/audio/gainclone.htm
The LM338 reg Ic is more expensive than the LM3875 power IC !
Carlos,
Seems we also put the chipamp to its limitation now. Just wonder what next innovation you will contribute to this forum 😉
How about this:
- Parallel chip amps with IC driver/buffer
- Chipamp as driver to Mosfet power stage
- Integrated (Chip)amp with NOS DAC
- Chipamp with High WAF ** Important*
( WAF = Wife Acceptance Factor )
Hee hee hee 😀
Carlos,
Seems we also put the chipamp to its limitation now. Just wonder what next innovation you will contribute to this forum 😉
How about this:
- Parallel chip amps with IC driver/buffer
- Chipamp as driver to Mosfet power stage
- Integrated (Chip)amp with NOS DAC
- Chipamp with High WAF ** Important*
( WAF = Wife Acceptance Factor )
Hee hee hee 😀
Hey Carlos, thanks for sharing this!
It's been a while since I changed my clone, I will dust off the soldering iron and get to work!
All the best
NG
It's been a while since I changed my clone, I will dust off the soldering iron and get to work!
All the best
NG
Yes, I'm going to try it as well. I'll sell the Krell to raise money for the extra parts! 😀 (Only joking Uncle Carlos but I will need to order the extra caps)
nina said:
I don't know. LM338 cost me less then LM3886, while both of them cost practically as one LM3875. In my local store(s).
LM338 = 4,4€
LM3886 = 5,3€
LM3875 = 9,3€
NealG said:
Welcome back, uncle Neal.
Long time no see.😎
PS: I will keep up with the thread tonight, I'm busy now with some SQL Server triggers.
LM338T is only USD$1.50 in quantities of 25 at digikey. I'd shop around unless you only need a couple.
Thanks Carlos for the research! I have a pile of regulator boards here that will be built up according your design.
Thanks Carlos for the research! I have a pile of regulator boards here that will be built up according your design.
tiroth said:
tiroth said:
I pay around 1.5€ a piece here, but if I look next door they ask around 4€ each.
You guys have to look around for the best price, don't take for granted the first quote you get.
Sometimes to buy some parts I go to 3 different places.
The guys that have the LM338s at 4€ have some other parts that are cheaper than at other places.
Buying electronic parts is a science.
XELB said:
I think 10,000uf will do, even for 4 ohm speakers.
Btw my speakers are 8hms, but not easy to drive.
You can ask to anyone who knows, has or sells Epos ES11 speakers (discontinued, ES12 later, M12 now) if it's easy to find a commercial amp that really makes them sing.
There are some, but $$$$$$.
Alcaid said:
No, it's not.
Go back to the first post again and check it out.
When I opened the thread and posted the schematic I saw that I had a reversed bridge (B2).
I corrected that and edited the post.
This was a question of minutes, maby you downloaded the first one.
The last think I want is to post a PSU that explodes in your faces.😱
😀
Nuuk said:
Nuuk, you have to make some stock at home.
I'm in a creative mood.😀 😀 😀
Well Carlos, I may be down on parts but a friend just dropped in with.......
An externally hosted image should be here but it was not working when we last tested it.
Good friend eh? 😉
Nuuk said:
😱
Are all those in working order?
Nevermind, either way, good friend.
Even if it's for recycling.
He said that they all had both traces working so I hope to get at least one good one from the three. There is also a digital bench voltage tester. 🙂
I just finished my unregulaterd Snubberized PSU 😀 😎
Since here is 1:15 AM, I could not test it loud and clear…
I will let the amp burn this night on and, in the morning, I will wake up everyone in the building! AH AH AH
LOL 
I'am using an STK4152II chip for testing 😉
Next step, regulated PSU 😀
Carlos, I that small store an 340VA-35V Toroidal transformer costs 40€ ( with instalation parts ).
Since here is 1:15 AM, I could not test it loud and clear…
I will let the amp burn this night on and, in the morning, I will wake up everyone in the building! AH AH AH
LOL I'am using an STK4152II chip for testing 😉
Next step, regulated PSU 😀
Carlos, I that small store an 340VA-35V Toroidal transformer costs 40€ ( with instalation parts ).
- Status
- Not open for further replies.