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I just used the Delete Cookies and logged back in. Same behavior as before.

Same since 8:00 am CST (first time I was on today). Advanced search doesn't help because it expects a keyword.

Yes, I agree, but I do not know where the 1W recommendation came from. It isn't noted in Kevin's hand-drawn schematic, and in Jacob's (j4cbo) first pass BOM spreadsheet, they are shown as RN55s or 1/4W PRPs.

Thanks, but if you read the thread completely, the ADA4898 will be used for buffering / SE->balanced conversion only. I/V will be done with a discrete stage designed by Colin Toole (cetoole here). Regarding the input filter: yes, I just noticed that when I posted this thread... not sure why I didn't see it (and remove it) when I replaced the NE5534s with THS4031s (with much bypassing).

R31-R34 don't look like they are set up for any power running thru them:

Actually there is quite a bit of room in there, though looking at them I'm not sure how you are supposed to mount them. I think I'll remain a wimp, though ya never know... BTW, is an I/V resistor the only other thing you need with these, or do you have to AC couple them as well?

Yeah, that gives a lot more insight into things, and makes my snarky post sound, well... snarky. So if the Appeal is ruled in favor of the plaintiff, what will the effect on Russ' business be? Is it a monetary judgment, cease and desist on the product in question?

I don't think you want to do a ground rod, but I'll let Kevin or someone with more experience weigh in on that. +1 on running new wiring, and probably plan for 20A circuits.

That one is nice and clean Colin. Fun toy

Ooops, guess I misunderstood you. The transformers are intended for I/V use? I assumed they were just for SE->bal conversion. I don't think I even want to try transformer I/V.

Mouser it is! Looking at the schematic for these (R31-R34), it appears that the CCS's are setup for ~4.5mA, so that is all that is running thru these (assuming I calculated this correctly... 1.6V LED - Vbe ~ 1V / 220 ohms). Footprint is identical to the other leaded/SMD resistor combos, so I am using 1/4W PRPs here.

Marc, I might take you up on that (transformers), for a listen. In order to get a sense of how much these would be should I like them so much I felt the need to buy some, what are they? Sowter? Filburt suggested replacing the ad8599s with ada4898-2s also.

2SA1145 / 2SC2705? Where to buy? I just looked thru my stash and don't have enough of these to do a pair of boards. Any suggestions on where to buy these? I assume Y grade is what I want (not O)? B&D has a few (only 6 SCs), and high price. Mouser has O grade for really cheap. Any other sellers? Anyone on ebay that can be trusted?

Just found a setting related to View New Content since last visit or View New Content Unread... think that did it.

Happy Birthday Grahame!

WTG Todd and all! One minor nit... I assume the View New Content in the upper right is the equivalent of view new posts in the previous iteration. When I hit it again after reading a topic (last post), it again shows that topic, but with no new content. Apparently not marking it as read.

Marc, From a previous post, this is the current recommendation? The series resistor is R62. This is not shown in the Eagle files I have from Jacob, which must have been a bit prior. My eagle files also have TO-220 vregs for the servo, etc. on it, which are not used if you are using the OPA445s for the servo opamp. The board itself has positions (unmarked) for TO-92 regs (7815/7915?) on it. I am going to jumper these and go with the OPA445. I am making updates to the BOM as I go. Also, I was missing the 620/680R, was short on 5K and 30K resistors, so when I did my Partsconnexion order, I used Dralorics here (626R, 5.05K and 30K), which are 0.25% or better resistors. Saved me from making a Mouser order, though that will still happen EDIT: anyone have the final Eagle files? EDIT2: For the 10R resistors, could we use 1/4 or 1/2W PRPs? Or do these need to be 1W? (Reason: I have some 1/2W PRPs)

I'm getting ready to build up one of Colin's tooleaudio I/V stages to put into my Rotel RCD-991. This is a dual PCM-63P player with pcm100 filter. I have currently been listening to it modded with THS4031s for the I/V stage and AD8599s doing the buffer/bal conversion. stock output stage: U302 is the single I/V opamp, U306 is the buffer/conversion opamp (dual) and U304 is an anti-aliasing opamp (socketed now, but not populated. I am trying to decide whether to Retain the AD8599s as buffers/conversion Replace the AD8599s with different opamps Use transformers? If so what? Other? I want to retain the muting relay functionality. The markup below is a first stab at what I think needs to be removed (green) as well as the output (to I/V stage) and input (from I/V stage) back into the player. DC coupled, so the coupling caps will be removed and jumpered. Any suggestions welcome.

Seems like russ has spent the last few years getting bitch slapped for claims made...

Happy Birthday!

Heh. Almost fell out of my chair... R19 and R20. I guessed right. And thanks for reminding me about that schematic as I had forgotten about it. The FB points clear up (somewhat) what is going on with the feedback loop choices. I put stake pins and 2 pos jumpers on for the "switch" for the feedback.

Marc, Before you leave, could you answer one of questions from post 1247?

Looks good Marc. Just needs a blue LED

I got some resistors last week (Parts Connexion sale), so am still working (slowly) on mine. I am going to socket the gain resistor (R55?) so I can more esaily play around with it. I do not have all the parts yet BTW, so don't expect any fire in the hole from me for some time... I'm trying to build these up as much as possible with stuff I already have. Since I am only using half of the output devices, any recommendation as to which positions on the board to use? At least I think I only bought that many FETs from you Marc? You can tell how much looking in my parts stash I have (not) done...