Heed canamp Mods Thread!! - Page 3

Wow! Thanks for the link, looks very interesting!



Now, if only I could cram a couple of these into my Go-Vibe!

LOL...when you finish there modding the HEED, you will ahve a completelly different amp, all discrete, and completelly different from what the designer manufacturer was thinking on while made it....insane how the audiophile mind works...it went from a OPAmp discrete buffer to a fully discrete amp...

Well FYI there are plenty of proven designs, from the books that will work fine, perfect, all discrete, without the need of doing this robocops!!!! and keeping only the front panel of an original amp....

i heard good things about the burson audio discrete "opamp"
btw, that can be modded as well. so in effect you mod the mod lol.

hehe, dont know if the thing will fit inside the case though!

also, i tried a few opamps, i used the AD823 initially and found it to be excellent

threw in the LM4652NA as well which to me was a step down, probably just my preferred sound but the AD823 had punchier tighter bass as well as better treble extension

i also tried the OPA2111 and OPA2107 and OPA2604 just for kicks but as expected, are too warm and mushy for my system. i had one opamp left and wasn't sure how it would fare, but for the sake of comparisson tried the DY2000 that came with my Zhaolu (now replaced with LM4652NAs) and WoW it had the treble extension and snap and verve of the AD823 but also some scarily realistic bass texture like no other i've heard

as always, your mileage may vary, seeing as my canamp is damn modded to the hell house! (thanks pink floyd) so it could just be synergy within my amp but also with the rest of the components down the line

but damn, the DY2000 just has a magical effect on the Canamp

anyone tried using dual-opamps like the 637s? How's the result?

I tried 2xOPA627's on a BD, very warm and laidback, but ultimately found the LM4562 to have the same characteristics but not as 'mushy'...

Of course, Alberto, half of me thinks you're absolutely right, but then the other half of me thinks you're just a sour old killjoy!

Well, agree with you to the point...Shematic diagram is one thing, the execution is another. From what I can see in CanAmp is the basic design as simple as it can get in this class of solid state amp. How the components are placed, ground planes routed on PCB, thickness of copper layers, PCB layer stack-up - I haven't seen a book that will tell you that. That's where Heed designer's skills came into play, and I have no doubts they've went thru several prototypes to produce a production variant, the sound of which we all admire and enjoy.

But no doubt either, compromises, driven most likely by intended selling price were made. Good example is power supply - silkscreen marking indicating that designer wanted to use larger capacitors there.

As for opamp rolling - I've resisted so far - reasoning that the whole CanAmp is build around NE chip and all been tweaked to get the best out of it. There are many BB and AD chips with better spec on the market and I'm itching to try DY2000 (I'll hear it soon at the coming Sydney meet - thanks d-cee ).

Again, coming from my technical background, rather than audiophile, I know from personal work experience that integrated opamp design carry several limitations that cannot be overcome due to size and thicness of silicone wafer the design is implemented on. The folks at Burson recognized this and came up with fully discrete opamp design that if done with precision and component matching as advertised - it should (in theory) beat any integrated opamp.

And that's where "mod happy DIY" guys find themselves rubbing their hands with anticipated SQ improvements.

i have some AD843s i'd love to try but need a browndog 2 x single > 1 x dual adaptor

if anyone woudl like to donate one @ the sydney meet and pop it inside my amp box i would be forever grateful

apart from that i've exhausted my opamp selection, of course, unless there are kind folks out there that would lend me some

D-cee,

haha i was just about to ask you the same thing!

i'll be bringing both 637's and 843kn's on browndogs so with you permission i wouldnt mind giving them a whirl. It will also give me some ideas for when spukee buys one and lets me at it!

If I remember when I tried the 843's they didn't work, are unstable. Hopefully yours won't be!

Had my hopes up for a while, but i am still curious to how they sound.
same problems with the 637's?


also all the resistors look like cheap jaycar jobbies, you think its worth replacing with vishays or prps? or is it more a case of errr 'bling'?

hmmmm i'd probably prefer if my canamp wasn't opened on the day

sorry, just paranoid since i won't be there =\

Is LM4562s really that good? When I got them they where really cheap. Also it was supposed to be less good with low impedance headphones...

I tried it on an x-meridian and it was surely better then stock though