Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,SPF_PASS,T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; Body=3 Fuz1=3 Fuz2=3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id v74EfYim011226 for ; Fri, 4 Aug 2017 16:41:35 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1dddg8-0007ov-7Z for rs_out_1@blacksheep.org; Fri, 04 Aug 2017 15:34:16 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1dddg4-0007ok-9f for rsgb_lf_group@blacksheep.org; Fri, 04 Aug 2017 15:34:12 +0100 Received: from mail-wm0-x231.google.com ([2a00:1450:400c:c09::231]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1dddg1-0003lu-DK for rsgb_lf_group@blacksheep.org; Fri, 04 Aug 2017 15:34:10 +0100 Received: by mail-wm0-x231.google.com with SMTP id m85so21411255wma.0 for ; Fri, 04 Aug 2017 07:34:09 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:message-id:to:subject:in-reply-to:references:mime-version :content-transfer-encoding; bh=xFG8diUATlVn67Js5SdJsOcPvUaQIOkatLuH+1MURcA=; b=AU+cw+CAeiiYwaN9GTzbbP1Ky/FfknupxXQtzsoHUhTAjtFo23B+J0v1EuJmCkrctC JCvsleaOzNQ3T/tkX0UiH/uCbCAAU/XocBrOnpAhrZv5KobUkKZ6p/dyXrVTEVPEymGG GBwj10dnhTpfmdjC5IVaE6baX3xdrVubrifvJ9+FhsTDKe8/6DTqucU8LV+BSg85hSAq ZJnUQLJBXLOhfzOvsxJlnUtgUzKIb1NN4/yMclD9IP5rSULMjixDYvJtc4czfU1TR8sD dkSI9RSn5JR/UblGtb6B+AWGG6EN7hZZmkS96C2gu+MTENYtnMkIcXxjNWUKZoUpF/RQ Y5Yg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:message-id:to:subject:in-reply-to :references:mime-version:content-transfer-encoding; bh=xFG8diUATlVn67Js5SdJsOcPvUaQIOkatLuH+1MURcA=; b=Ze2XFEIqDfPuWVGoebyIgYjF2mEv8lpIwvkX6O3NrfjWcAec0UdEqAsynAzDUK+69z foxfSf+k0YhF3tfR1fAvmPKiLjt5NtQw5ev+PQx5Sm2HdiWWbFRaGdK+4rWbMcOd63tu RETjNHnCDz7943dbKRR7w3Y1lhZfSjqEDelXtWCp8oQloQUk5wIsiPgV1QkEZWlGz8KZ fe3XrahsJlFJTZ5M5022P3uGAOLV0geKslaS6O2bwHCRFlwrx4dpiuG2ckuoeHGGgtI0 o4a97KmdyOYbZkOR0ZqSUwp4stC3ISsJITOLtef6HR9esZfkNuAejV1X0hFioqBwZkNC vRtw== X-Gm-Message-State: AHYfb5ixBYERxOmKWjR7YrZKcNQzwAy4aCVtU8hI6aw/8E2Qrg0mvbq6 R2cxPnSOSMC03rZX X-Received: by 10.28.218.201 with SMTP id r192mr1798238wmg.36.1501857248211; Fri, 04 Aug 2017 07:34:08 -0700 (PDT) Received: from OfficeWin7.lan (82-70-254-222.dsl.in-addr.zen.co.uk. [82.70.254.222]) by smtp.gmail.com with ESMTPSA id a134sm3614007wma.47.2017.08.04.07.34.07 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 04 Aug 2017 07:34:07 -0700 (PDT) Date: Fri, 4 Aug 2017 15:34:06 +0100 From: Chris Wilson X-Priority: 3 (Normal) Message-ID: <42526801.20170804153406@gmail.com> To: Clemens Paul In-Reply-To: References: <791401561.20170803151834@gmail.com> <9eb8f313-3b17-9da7-7e3e-3d77b2137080@t-online.de> MIME-Version: 1.0 X-Scan-Signature: 0a4643e586472c13187d293ec5d096c2 Subject: Re: LF: RE: LPF for a valve based (tube based) LF amp? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.75 Status: O X-Status: X-Keywords: X-UID: 12322 Hello Clemens, Friday, August 4, 2017, 2:36:22 PM, you wrote: > Hi Wolf, > ok about the tank circuit. > Do you think that it does not provide enough attenuation for the harmonics > so that you need an extra LPF on LF? > 73 > Clemens > DL4RAJ Thanks for the replies, I was wondering this myself as few tube amps use an LPF.... Opinions very welcome (and needed ;)) I was going to drive it with one of my FET amps on a lowish voltage, not sure how much drive a GS35B would need to give a healthy output though, 50 watts maybe? More? -- Best regards, Chris mailto:dead.fets@gmail.com