This has to rate right up there with cutting out the analog filter in both ease of execution and benefit. Move one wire and it makes a huge difference. I certainly did not expect much of an increase in sound from this mod but I was wrong. Certainly more open and detailed yet retaining the sense of realism that the NOS guys are usually looking for.
Some guys may not experience quite as much benefit depending on their sources but with my Northstar transport it worked quite well. Certainly worth the minimal time and effort to try. Thanks Steve Nugent and Bill Allen for this one!
Bill's explanation of how to do it is buried in a paragraph on how to wire up the digital filter cap so to make it clear: de-solder the wire of your SPDIF ground from the DAC board and solder it to pin #2 on the pulse transformer (the bottom of the input side). There is a nice fat solder point to the left of that pin that is easier to solder to than the bottom of the SMD 75 ohm resistor. Done.

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Its wired correctly

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I was wondering were best to put that earth, many thanks for spelling it out driguy. Easy peasy. when you explain it!

I have not measured mine but: since the 7.5 and 5 volt rails come after the same filter it seems unlikely that there should be AC on one and not the other. That being said, it could be a less than perfect regulator. Try adjusting it up or down just slightly to see what happens. No matter what the outcome, yes, you can use the Wima's to further the filtering of the 5 volt rail AFTER the regulator. Just solder them across the 5 volt tab and ground the same way as the current reservoir setup. Again, closer to the load is better here as well. As the digital side does not have near the current requirements or changes as the 7.6 volt side you may not sense much gain. Let us know what you hear and measure. Also, if it makes no difference just move the 5 volt wire over to the 7.6 volt tab and you will get a difference there for sure. You can use one cap for the 5v and one for the 7 volt rail to make yourself really happy.

driquy, have you any thoughts on the actual stock pulse transformer?

are you sure? bill did it differently.. he took the power going from the main pcb to the dac board as opposed to the inlet. here's a picture.

Picasa Web Albums - Bill - Chameleon

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No, it sounds really good and I have not heard another unit yet.

I thought your were concerned that the caps were not bypassed correctly. Yes indeed will move it closer to the chip board later, which will reduce the distance further between the resevoir and the Dacs, and bypass the copper tracks. Bill has used long leads here, obviously he intends to also move the resevoir closer as well at some future date.

Are you going to give it a go as well Mike, I would like to know your findings?

Oh by the way Mike I measured those Jupiters for you they are 8cmx4cm. But I had to take out the spidf/toslink switch to fit them.

Last May I had converted my 3 car garage into a 20 X 3O foot finished listening room, with 10 foot ceiling, French door & Bay window to open up the space. On one end lives my Hi-Fi system on the other a deluxe soldering bench and cabinets. It's very cool, you can solder at the same time you're listening, the ultimate DIY Audio "Man Cave". After a 9 month hiatus from the remodel, I finally dusted off my Kondo Ongaku amp and put it back in my system. Why so long, perhaps quilt pangs from possessing such an exotic piece while experiencing a short term financial crunch. Another words I should sell the damn thing to get out of debt. However I came to the conclusion that if my wife won't sell her big diamond ring then I'm not selling my Ongaku. Armed with this logic she caved in ... the Ongaku can stay.

Long story short my friend Jonathan (who helped with and concieved the remodel plan) came over to assist with the set up of the Ongaku. He also provided 2 extra hands while performing the FIM/FRM mods. Thanks Man! We were clearly able to hear the net results from these simple mods with the Ongaku in the system. We were both blown away that such small changes could yield such significant gains. Being an audio minimalist himself he suggested we try the Chameleon DAC direct into the Ongaku without my preamp. After all the Ongaku is an intregrated amp even though I always employed it as a straight power amp. Well it didn't perform well through the "direct input" which bypasses the Ongaku's input tube, however it came through with flying colors (literally) when fed through the tape input which employs both triode sections inside the 12AY7 input tube. Comparing it 3 separate times, it was no contest; my long standing single stage preamp had been beat. We then switched over to my hi-end analog rig that Jonathan always found superior. Once again the Chameleon came out on top, now that’s a very tall order my friends. His final conclusion, the modded Chameleon DAC/Ongaku has taken my system to a whole new level. I agree.

I met Kondo San at the 2002 CES show and he gave me a peak inside his new Ongaku DAC where I saw for the first time 16 DAC chips per channel, crazy I thought, as was the $25K price point. The sound was awesome and I never forgot it. (Jonathan I'm sure tired of me talking about it over the years). Well maybe my memory is jaded but my modded Chameleon is every bit as melodic as I recall the sound of that Ongaku DAC. It's been a long road my friends, Kondo has shifted dimensions, and the new KSL Kondo DAC doesn't move me this same way. Water under the bridge.

My underlining point of this whole story is my modded Chameleon DAC has stepped up and proven itself to me. Its utter simplicity has the potential of reaching exalted levels of performance with the right parts and tweaks. Its measured performance might be an enigma but IMO it demands as much attention as we care to bestow upon it. The word Chameleon really does reflects its nature, color it anyway you want, the sound will still be fantastic. Me I want mine near white, so next up are Dueland coupling caps, 2 DC-30 power supplies, direct I2S input, and another 16 chip DAC board for true dual mono operation. In a way this is my tribute to honor the memory of Kondo San, a man who showed the world that superior materials and simple circuits are the road to audio nirvana … RIP.

I did hook those 2 wima's up like bill has his. Immediate impressions, more warmth/body/bass snap. The bass improvement is nice. Might push things a little to warm, but with only 15 hrs on the Silmic's who knows. Im about to take the DC30 apart again and try to adjust the +5 voltage trim, as suggested.

Can I use a spare 100Uf Silmic as a filter cap? Or is this counter-productive being an electrolytic

edit: the wima's arnt fully burned in either, they got about 120 hrs on them.

I have to say this Chameleon with the most recent mods you guys are cooking up, (just followed driguys instructions for the spidf earth) have utterly floored me. I was expecting superb results from this dac having heard what the Valab does. But this is just getting out of hand. I can't come to terms that it sounds this good now, and yet non of the caps I have installed have even started to burn in. If I do nothing now, except wait, I cannot imagine how good it will sound in a months time, I have no point of reference anymore, other then the dac itself.


And then I see you last comment Bill, on your Picasa Album 'However even after all this work everything tells me the BAM Mod is far from complete.' I'm well and truly Gobsmacked.

driguy made a simple sentence on this which unhid it from Bill's descriptions. Now this is so simple to bring the neg along with the pos that you have to wonder why did we not see it first when we brought that pos over?!?!?!

Anyway, thanks again Bill and driguy for making it plain what to do.

My transport is not close to the best. not even in that neighborhood, but I saw a nice response. You get more of what the transformer gives, the personality, or lock to, or whatever you want to call it. It is always with vocals I appreciate it most so when Betty Roche pulls back form the mic you hear that.

Someone mentioned something about diminishing returns. It is the small subtle things which really makes the texture of things tasty. The big bang response from a mod is a kick but these small things should never be shelved under diminishing returns. Not sure anyone IS doing that; the thought just intruded.

I think the way Bill tipped his transformer is the way I will do it to get it off there - lift the Pulse then clip it off leaving the pins and tac the new transformer on.

And since a picture is worth a thousand words ...

Mike, I found an easy and aesthetic way to keep the DC-30 a little cooler. I just put 8 small washers between the case and front and back panels, were the screws go, and screwed it back together. You then get a small air gap at each end of the DC-30.

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At the risk of adding fluff I gotta say even without all the mods so far this frigging thing whips ass. I have TX resistors coming in the mail and am ordering some Fine Gold caps for the DACs ... a question on that: Why are we keeping the .1uF bypasses? Shouldn't we remove those from the DACs when adding the 47uF?