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Radiohead - Chicago 7-7-2018 United Center Sent from my iPhone using Tapatalk

Got mine the other day, looks great. Thanks!

Happy Birthday Jose! Sent from my iPhone using Tapatalk

Happy Birthday Birgir!

Happy Birthday Mike!

Very nice Michael!

Documentation? heh Which amp? This is a confusing thread because there are at least 3 amps discussed here, maybe more (Kevin or others, correct me if I am wrong): CFA2 (CFP) - current feedback amp. Each board does 1 channel SE, so 2 for stereo SE, 4 for stereo balanced. Kevin later did a mod to this adding current mirrors feeding the servo. People who had built the original noticed that the servo was audible as to quality of opamp. The schematic in Kevin's archive is the older version. CFA3 - current feedback amp for balanced. Not sure if anyone ran boards for this one. Basically a pair of CFA2 amps and ubal-bal board on one pcb. Schematic does not show the current mirror mod as in 1 above uberamp - seems to be a power amp; I've never quite figured this one out Here are the schematics for the CFA2 (current mirror version), and the CFA3. I also attached my BOM for a CFA2. Amp quantity shown is for stereo SE. If going balanced, double it. It should reflect the later current mirror version. You'll also need some GRLVs or other power supplies, etc. cfa2cmirror.pdf cfa3production.PDF CFP2_BOM_update2018march.xlsx EDIT: I also ran across another schematic on Kevin's site which I hadn't seen before: currentsourceamp2.PDF. This seems very similar to the cfa2cmirror schematic, but is described as a transconductance amp.

As Kevin said, probably not too hard to fix. Needs a lot of attention to the wiring in there though, starting with the transformer leads.

Thanks for all of the hard work Steve!

Happy Birthday Greg!

Happy Birthday Justin! Sent from my iPhone using Tapatalk

^ this Sent from my iPhone using Tapatalk

On my commute, I have been using Apple Earbuds, which seem to leak a bit of sound. I am normally riding on a train car designated as "Quiet Car" and have had a couple of people look at me if I'm really cranking something, so I was looking for something that didn't leak as much. I know, JH13 I ran across the HifiMan HE400s on innerfidelity, which Tyll seemed to like, and can get these for around $50. I also noticed they have an HE400i (iPhone) or HE400a (Android). From what I can tell, these do not have a microphone, but do have the inline volume control thingy? The reviews seem to indicate that the inline controls are cheap and break. I never really use these, but if they did have a mic in them, could be useful. This is for use with an iPhone 7 or 8. Sound-wise, the Apple ear buds are fine, but better of course would be appreciated.

I tossed together a BOM for the SS Balanced Dynahi using the PZTA SMD transistors, MJE15030/15031 outputs. It is missing connectors, etc. but looking at the v1.5 gerber file (ssdynahibalsmt.zip), it matches the board (I think) SS Balanced Dynahi BOM.xlsx

Perhaps I was a bit harsh? The 1K resistors I see on the schematic I have are on the collectors of Q1/Q2, feeding the + inputs on the error amp. Not sure if going 10K here would make any difference whatsoever. ksa5psschem.pdf

I've got a set of boards that I would let go. I'll have to check what version they are.

I guess I get the allure of kits from ebay for the cheap prices, assuming the components are a) genuine, and b) decent quality. However, buying a kit and then coming on here without apparently doing a modicum of research first is very bad form. The links to Kevin's board files and schematics/other files are here, but might require a bit of digging. Since that vendor supplies both kits and built units (for a whopping $10 more), one might assume that they build with the same parts as they supply in the kit, and it might not matter whether you use a 1K or 10K resistor in the 2 spots. If you're worried about it, then use some 1K for those two positions. But otherwise, the appropriate head-case response is...

Happy Birthday Kerry! Sent from my iPhone using Tapatalk

J/k Jim Sent from my iPhone using Tapatalk

Damn Jim, you sound like you and Wayne LaPierre are best buds

I'm guessing non-English speaker?

Holy shit! Loved watching his stuff... RIP Anthony Sent from my iPhone using Tapatalk

^Probably (respect any pinout differences). I think they are effectively the same transistor/die. The only thing that could potentially be a problem would be cooling. I know the pzta parts were put in because of that (power going beyond the BC capability and the MPSW being discontinued).

Thanks for all of your work! Sent from my iPhone using Tapatalk

Getting an error trying to login. Using current password, login etc. I get an error saying that it can't find a user with my email address, and then tells me to log in manually. When I try to do that, it says: Server error occurred: '1 Call to undefined method IPS\Login::forms()(MbqRdEtUser.php:29)'