Search found 7 matches

by dirkwright
Tue Nov 17, 2015 4:17 pm
Forum: Pro Audio Design
Topic: Flat Phono Preamp Based on John's P10 and 2SK389
Replies: 239
Views: 254823

Re: Flat Phono Preamp Based on John's P10 and 2SK389

I don't understand the desire to provide a phono preamp that does not have the RIAA de-emphasis EQ built into it. Since the vast majority of LP's were recorded using analog filters for the RIAA emphasis, then they have phase shifts that are built into the LP itself. The analog RIAA de-emphasis EQ ha...
by dirkwright
Tue Nov 10, 2015 4:36 pm
Forum: Build
Topic: Wayne's Mic Pre photos (By Joe Neil aka Bruno2000)
Replies: 9
Views: 26094

Re: Wayne's Mic Pre photos

Very neat and tidy. Good job!
by dirkwright
Tue Nov 10, 2015 4:34 pm
Forum: Build
Topic: Simple pcb design program
Replies: 28
Views: 33709

Re: Simple pcb design program

Unless you are going to manufacture your own boards, I don't see a reason to have a PCB layout software and Gerber file generator myself. You'll still have to pay the minimum set up fee and other costs with any of the PCB manufacturers out there. I use Pad2pad. It is very easy to use, and they have ...
by dirkwright
Tue Nov 10, 2015 2:31 pm
Forum: Pro Audio Design
Topic: LM4562, LME49710, LME49720 Start-up Behavior
Replies: 42
Views: 80515

Re: LM4562, LME49710, LME49720 Start-up Behavior

Thanks for letting me join! The rep from TI said that the TO-99 version of these opamps was not being discontinued. I don't know why. They are excellent opamps and I use them in my designs a lot. It's the first chip I go to because it behaves so well. My guess is that the TO-99 version is used in mi...
by dirkwright
Tue Nov 10, 2015 1:37 pm
Forum: Pro Audio Design
Topic: Laying out a PCB
Replies: 6
Views: 16134

Re: Laying out a PCB

I use Pad2Pad. It's easy to use and they treat me well. I do not use electrolytic capacitors for IC power supply bypass. Put two large electrolytics where the power connects to the board, and then use MLCC's at each power supply pin on each IC, as close to the pin as possible. 0.1uF MLCC is plenty f...
by dirkwright
Tue Nov 10, 2015 12:39 pm
Forum: Pro Audio Design
Topic: LM4562, LME49710, LME49720 Start-up Behavior
Replies: 42
Views: 80515

Re: LM4562, LME49710, LME49720 Start-up Behavior

Most of the LME series is EOL. Last buy date is next September as I'm sure you all know. However, the LME49710/20 lives on in the TO-99 package. as well as the LM equivalent. The 44V versions are completely gone. I was told by TI that they decided to end a particular manufacturing process as the mai...