Will a single "Ripple Eater" supply a stereo pair of boards? I see Jims Audio sell a pair of Kx boards with a pair of Ripple eaters. Do I need 2 Ripple eaters?
Do you plan on building Class AB or AAB or do you want Class A to 25watts peak/8 ohms as well? Class AB and AAB settings in this amplifier design allows for a bit more ripple on the supply.
For Class AB and AAB, a single Ripple eater with 33-47mF per rail should be more than fine and it should work “well” with Class A builds as well (where current peaks of 2.5A will be required given the quiescent current being 1.2A).
But given that this is DIY and I am conservative, dual ripple eaters in a Class A build will be better if chassis space is not a concern. It will reward you with “blacker blacks” and a lower noise floor. High bias Class A is much more demanding on the supply as well as thermally on the heatsinks.
Best,
Anand.
If you use the Jim's audio ripple eater (it's actually a complete power supply with smoothing caps and ripple eater) I suggest you replace the MJE1503X devices with NJL 1381/1302 TO3P devices and mount these devices on your main heatsink and run short wires well twisted to the devices. This is what I have in my kx2 although I only used 1 ripple eater board. The original MJE1503X devices really can't handle full power testing into 2 ohms.
I fell in love with this amp and ordered two more with two ripple eaters. A newbie question, out of curiosity I'd like to try a different power supply than the one that came with the kit. Where should I connect the speaker return J1 ? The transformer is 19+19v ac. Also where can I find the ripple eater bom? In the bonsai site I can't download it.
It’s in Excel format. Should be downloadable.
Is it the Micro Ripple Eater? This is only available from www.hifisonix.com. Here is the BOM ：-
Is it the Micro Ripple Eater? This is only available from www.hifisonix.com. Here is the BOM ：-
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Here is the BOM for the ripple eater board sold only by Jim’s Audio. This one is a complete power supply with reservoir capacitors etc. Please replace the MJE1503X devices with NJW1302 and NJW3281 and mount the devices to your amplifier heat sinks. Any help you need, let me know.
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Looks good Bonsai. Perhaps also add in the ‘notes’ section, the preferred option of NJW1302/3281 to make it stable for larger current demands like 2 ohm loads.
Best,
Anand.
Here’s the link to the hifisonix page with all the details on how to beef it up
(This is the one sold by Jim’s Audio)
https://hifisonix.com/simple-ripple-eater-psu-for-the-sx-and-kx-amplifiers/
(This is the one sold by Jim’s Audio)
https://hifisonix.com/simple-ripple-eater-psu-for-the-sx-and-kx-amplifiers/
all hello ! my kx2 Amplifier. photo not very in detail at in Ukraine now problems with electricity. a strengthener on sounding is magnificent ! I listen with Canton CT 90 and BOSE 601 Series I. many thanks Bonsai !
In the schematic of ripple eater C1 and C6 they are 47uF but in the order code of the bom they are 47000uF. I think 47000uF is right. Can you confirm please?
Hello,
it's shown as 47mF which is milli-Farad aka 47 000 uF 🙂
Per notes on the build page, it is recommended you use TO-3P or TO247 devices for Q1 and Q3 - see the build page here for more details http://hifisonix.com/simple-ripple-eater-psu-for-the-sx-and-kx-amplifiers/
If you are building a kx2-Amplifier, you can leave off R7, R8 and C2 and C3 as these are fitted on the kx2-Amp amplifier modules. For the sx and nx-Amps you will need them.
it's shown as 47mF which is milli-Farad aka 47 000 uF 🙂
Per notes on the build page, it is recommended you use TO-3P or TO247 devices for Q1 and Q3 - see the build page here for more details http://hifisonix.com/simple-ripple-eater-psu-for-the-sx-and-kx-amplifiers/
If you are building a kx2-Amplifier, you can leave off R7, R8 and C2 and C3 as these are fitted on the kx2-Amp amplifier modules. For the sx and nx-Amps you will need them.
Thanks again bonsai. Yes I'm assembling two other beautiful kx2. It's all easier when you receive precise and fast explanations!
If anyone has assembled Jim's boards or amps. I'd greatly appreciate some pics. I'd would like to see how builders put it all together. And how its done. Thanks