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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>There are places that still sell parts for both music and audiophile tube amps. So check the internet.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Here's one:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://www.tubesandmore.com/">https://www.tubesandmore.com/</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Jay S.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Synth-diy [mailto:synth-diy-bounces@dropmix.xs4all.nl] <b>On Behalf Of </b>Richie Burnett<br><b>Sent:</b> Saturday, March 26, 2016 1:21 AM<br><b>To:</b> synth-diy; cheater00 .<br><b>Subject:</b> Re: [sdiy] HV capacitors for tube amp<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>450v is high for modern electrolytics. You can use two lower voltage and larger capacitance caps in series with balance resistors if necessary.<br><br>You didn't say what the capacitance was, but you might be able to find plastic film caps with a large enough capacitance. Power factor correction capacitors (PFC) are film-foil construction, up to 450VAC and low loss, but they are likely to be physically much larger than the equivalently rated electrolytic capacitors.<br><br>Anything marked low-ESR and rated 105'C from the likes of Panasonic, Rubycon, Vishay/BC components, or Nippon-Chemicon should be decent quality.<br><br>-Richie,<br><br>P.S. Be careful, the stored energy is very likely lethal at those voltages!<br><br>Sent from my Xperia SP on O2<br><br>---- cheater00 . wrote ----<br><br>Hi guys,<o:p></o:p></p><div><p class=MsoNormal>I have to replace the DC HV filter capacitors on my Mesa head. They're 450V electrolytics running at maybe 420V and have a footprint of 12mm at the base. They dried out after ~6 years. I would like to replace them with good ones that have very low ESR in the audio range. This amp has a problem where gain stages leak to each other, and I suspect that happens through the HV bus. If need be I can use capacitors with a different footprint, I could build a scaffold since everything is TH.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Is there anything that would suggest against using MKT capacitors here?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I also thought about using pairs of large and small capacitor to compliment frequency response of impedance.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Links to suppliers or part #'s would be great.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks<o:p></o:p></p></div></div></body></html>