mhardy6647
Lunatic Member
Howdy:
I have a working but tired EICO HF-81 stereo PP EL84 integrated amp that I'm feeling like (finally) sprucing up. There are several on-line resources for upgrading this amp (e.g., Kelly "mobile homeless" Holsten and Roger Stevens), but they tend to aim a little higher than I would. Attached photo 'borrowed' from Kelly's site: http://home.earthlink.net/~eico_hf81/index.htm
I am thinking of changing the two P/S caps under the deck and the coupling caps. Looking for suggestions beyond that. Stevens' site suggested changing cathode bias resistors to 'lower the temp'. The amp does run dang hot (an EICO tradition, as I recall) so that's tempting. Anyone here bypass or otherwise 'improve' the FOCUS (balance) control? I still don't get how that's supposed to work.
Also, the tubes in this particular amp are a hodgepodge. Since the HF-81 uses a mess of 12AX7's (and some 12AU7's, too, IIRC), I was wondering if anyone had any opinions about any current production 12AX7's that were "OK"... not looking to rival classic tubes, just something that'd work and not be embarassing, or awful, to listen to.
Thanks as always for your attention.
I have a working but tired EICO HF-81 stereo PP EL84 integrated amp that I'm feeling like (finally) sprucing up. There are several on-line resources for upgrading this amp (e.g., Kelly "mobile homeless" Holsten and Roger Stevens), but they tend to aim a little higher than I would. Attached photo 'borrowed' from Kelly's site: http://home.earthlink.net/~eico_hf81/index.htm
I am thinking of changing the two P/S caps under the deck and the coupling caps. Looking for suggestions beyond that. Stevens' site suggested changing cathode bias resistors to 'lower the temp'. The amp does run dang hot (an EICO tradition, as I recall) so that's tempting. Anyone here bypass or otherwise 'improve' the FOCUS (balance) control? I still don't get how that's supposed to work.
Also, the tubes in this particular amp are a hodgepodge. Since the HF-81 uses a mess of 12AX7's (and some 12AU7's, too, IIRC), I was wondering if anyone had any opinions about any current production 12AX7's that were "OK"... not looking to rival classic tubes, just something that'd work and not be embarassing, or awful, to listen to.
Thanks as always for your attention.