Forums
New posts
Search forums
What's new
New posts
Latest activity
Members
Registered members
Current visitors
Log in
Register
What's new
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
DIY & Tutorials
DIY For Audio
I want to build my own amplifier
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Help Support AVForums:
This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Message
<blockquote data-quote="ludo" data-source="post: 74575" data-attributes="member: 691"><p>You gotta fix the routing for gain setting resistors on the pre so they go to the inverting inputs before you print this one. I guess you've seen it by now.</p><p></p><p></p><p>But impressive. I just have some questions about this one, seeing as I never really had a chance for a proper listen to the LM3886 board I put in the Steinhart box.</p><p></p><p>Does one really need a preamp?</p><p></p><p>With 18-0-18 transformer and the minimum gain of 10 on the LM3886 I'd think one can have it clipping quite easily. (And snort and scream it does then ;D) The LM3886 seems to have diamond buffer inputs so should be pretty tolerant of high impedance drive straight from a pot?</p><p></p><p>Is the preamp just there because folk have this natural aversion to turning volume pots past 12 o'clock?</p><p></p><p>Also, would the cap in the feedback loop of the LM4562 not be serving a better purpose in the feedback loop of the LM3886? I had surprisingly low offset voltage on the poweramp output (1-2mV) that way. A DC coupled feedback loop with a cap just on the input of the 3886 was less good on a later attempt and it went above 100mV.</p></blockquote><p></p>
[QUOTE="ludo, post: 74575, member: 691"] You gotta fix the routing for gain setting resistors on the pre so they go to the inverting inputs before you print this one. I guess you've seen it by now. But impressive. I just have some questions about this one, seeing as I never really had a chance for a proper listen to the LM3886 board I put in the Steinhart box. Does one really need a preamp? With 18-0-18 transformer and the minimum gain of 10 on the LM3886 I'd think one can have it clipping quite easily. (And snort and scream it does then ;D) The LM3886 seems to have diamond buffer inputs so should be pretty tolerant of high impedance drive straight from a pot? Is the preamp just there because folk have this natural aversion to turning volume pots past 12 o'clock? Also, would the cap in the feedback loop of the LM4562 not be serving a better purpose in the feedback loop of the LM3886? I had surprisingly low offset voltage on the poweramp output (1-2mV) that way. A DC coupled feedback loop with a cap just on the input of the 3886 was less good on a later attempt and it went above 100mV. [/QUOTE]
Insert quotes…
Verification
Post reply
DIY & Tutorials
DIY For Audio
I want to build my own amplifier
Top