https://aronnelson.com/diywiki/index.php?action=history&feed=atom&title=FET_GainFET Gain - Revision history2026-08-10T23:29:53ZRevision history for this page on the wikiMediaWiki 1.30.1https://aronnelson.com/diywiki/index.php?title=FET_Gain&diff=1396&oldid=prevDave: Please delete this page. Contents have been moved to a more appropriately named page.2006-05-01T16:45:09Z<p>Please delete this page. Contents have been moved to a more appropriately named page.</p>
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<td colspan="2" style="background-color: white; color:black; text-align: center;">Revision as of 16:45, 1 May 2006</td>
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<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">'''[http://www.geofex.com/ R.G.]''' </del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">To change JFET stage's gain, change the unbypassed source resistance.*  ... You can change gain easily by inserting unbypassed source resistance, and probably should do it that way instead of swapping JFETs at random. The J201 is a high gain device, so it's easy to turn the gain down.</del></div></td><td colspan="2"> </td></tr>
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<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">'''[http://www.runoffgroove.com/ B Tremblay]'''</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">Our basic rule of thumb has been that if a bit less gain is needed, swap out the J201 for an MPF102 or 2N5457.  A side effect is that the overall tone will become brighter.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">However, those three types were usually only ones we'd try while developing FET-based amp emulators.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">We didn't choose those types according to datasheet specs; they're simply three of the more common FETs in the realm of DIY-fx.  It's not very scientific to be "easter-egging,"  but doing so would sometimes produce pleasing results.</del></div></td><td colspan="2"> </td></tr>
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<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">Text taken from [http://www.diystompboxes.com/smfforum/index.php?topic=28810 this thread].</del></div></td><td colspan="2"> </td></tr>
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<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"><nowiki>*</nowiki> '' paraphrased''</del></div></td><td colspan="2"> </td></tr>
</table>Davehttps://aronnelson.com/diywiki/index.php?title=FET_Gain&diff=1391&oldid=prevDave: Added page2006-05-01T14:48:39Z<p>Added page</p>
<p><b>New page</b></p><div>'''[http://www.geofex.com/ R.G.]''' <br />
<br />
To change JFET stage's gain, change the unbypassed source resistance.* ... You can change gain easily by inserting unbypassed source resistance, and probably should do it that way instead of swapping JFETs at random. The J201 is a high gain device, so it's easy to turn the gain down.<br />
<br />
<br />
<br />
'''[http://www.runoffgroove.com/ B Tremblay]'''<br />
<br />
Our basic rule of thumb has been that if a bit less gain is needed, swap out the J201 for an MPF102 or 2N5457. A side effect is that the overall tone will become brighter.<br />
<br />
However, those three types were usually only ones we'd try while developing FET-based amp emulators.<br />
<br />
We didn't choose those types according to datasheet specs; they're simply three of the more common FETs in the realm of DIY-fx. It's not very scientific to be "easter-egging," but doing so would sometimes produce pleasing results.<br />
<br />
<br />
----<br />
Text taken from [http://www.diystompboxes.com/smfforum/index.php?topic=28810 this thread].<br />
<br />
<nowiki>*</nowiki> '' paraphrased''</div>Dave