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I'm quite excited about our little SPICE comparison.

I've never used LTspice for noise before and it is showing and confirming stuff which Guru Wurcer and I played with at the beginning of this Millenium ... all in MicBuilders for those really interested and maybe his Linear Audio articles.

Let's tie down some important but non-controversial details.
THOR'S CAPSULES

You proposed 2 capsules. The first was a 34mm 'Brass' capsule of 68p capacitance and -34dBV/Pa sensitivity @ Vp = 60V

This is appropriate for the comparison between your circuit and Zephyr's. It is what Zephyr had on his capsule. I'll allow you to assume Vp = 60V though your circuit only has about 42V

The other was an electret 26mm, 42p and -35dBV/Pa. This is good to compare your circuit with SimpleP48 & SimpleP48RCA

Are you happy with these choices of capsules you recommended?
MIKE PREAMP

In #319, I assume a simplified version of Fig 9 in THAT Corporation 1510/1512 Datasheet rev9 5oct2017.

You assume a slightly different 'simplified' preamp in #245

Which one should we use?

I'm happy to use yours cos it sometimes gives SimpleP48 & SimpleP48RCA a slight advantage

<blockquote data-quote="ricardo" data-source="post: 1185559" data-attributes="member: 45377">I&#039;m quite excited about our little SPICE comparison.I&#039;ve never used LTspice for noise before and it is showing and confirming stuff which Guru Wurcer and I played with at the beginning of this Millenium&nbsp;&nbsp; ...&nbsp; all in MicBuilders for those really interested and maybe his Linear Audio articles.Let&#039;s tie down some important but non-controversial details.<hr />THOR&#039;S CAPSULESYou proposed 2 capsules.&nbsp; The first was a 34mm &#039;Brass&#039; capsule of 68p capacitance and -34dBV/Pa sensitivity @ Vp = 60VThis is appropriate for the comparison between your circuit and Zephyr&#039;s.&nbsp; It is what Zephyr had on his capsule.&nbsp; I&#039;ll allow you to assume Vp = 60V though your circuit only has about 42V&nbsp; <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile&nbsp; &nbsp; :)" loading="lazy" data-shortname=":)" />The other was an electret 26mm, 42p and -35dBV/Pa.&nbsp; This is good to compare your circuit with SimpleP48 &amp; SimpleP48RCAAre you happy with these choices of capsules you recommended?<hr />MIKE PREAMPIn <a href="https://groupdiy.com/threads/comparison-of-jfets-for-mic-applications.86559/post-1184996" target="_blank">#319</a>, I assume a simplified version of Fig 9 in THAT Corporation 1510/1512 Datasheet rev9 5oct2017.You assume a slightly different &#039;simplified&#039; preamp in <a href="https://groupdiy.com/threads/comparison-of-jfets-for-mic-applications.86559/post-1184120" target="_blank">#245</a>Which one should we use?I&#039;m happy to use yours cos it sometimes gives SimpleP48 &amp; SimpleP48RCA a slight advantage&nbsp;&nbsp; <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile&nbsp; &nbsp; :)" loading="lazy" data-shortname=":)" /></blockquote>

[QUOTE="ricardo, post: 1185559, member: 45377"] I'm quite excited about our little SPICE comparison. I've never used LTspice for noise before and it is showing and confirming stuff which Guru Wurcer and I played with at the beginning of this Millenium ... [I]all in MicBuilders for those really interested and maybe his Linear Audio articles.[/I] Let's tie down some important but non-controversial details. [HR][/HR] [B]THOR'S CAPSULES[/B] You proposed 2 capsules. The first was a 34mm 'Brass' capsule of 68p capacitance and -34dBV/Pa sensitivity @ Vp = 60V This is appropriate for the comparison between your circuit and Zephyr's. It is what Zephyr had on his capsule. I'll allow you to assume Vp = 60V though your circuit only has about 42V :) The other was an electret 26mm, 42p and -35dBV/Pa. This is good to compare your circuit with SimpleP48 & SimpleP48RCA Are you happy with these choices of capsules you recommended? [HR][/HR] [B]MIKE PREAMP[/B] In [URL='https://groupdiy.com/threads/comparison-of-jfets-for-mic-applications.86559/post-1184996']#319[/URL], I assume a simplified version of Fig 9 in THAT Corporation 1510/1512 Datasheet rev9 5oct2017. You assume a slightly different 'simplified' preamp in [URL='https://groupdiy.com/threads/comparison-of-jfets-for-mic-applications.86559/post-1184120']#245[/URL] Which one should we use? [I]I'm happy to use yours cos it sometimes gives SimpleP48 & SimpleP48RCA a slight advantage :)[/I] [/QUOTE]

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