Response I received from Anthem
thsmith
Posts: 6,082
I needed 2 feet for my Anthem AMP 1. I also queried about a circuit board as a spare since this AMP is Manufactor Discontinued.
My question is, since I am using a 5751 which I believe has less gain than 12AX7. IS it okay to bias at the level Anthem suggest (below)? I reconize I could ask them and probably will but 5751 is not one of their suggested 12AX7 replacement tubes.
Quote from Anthem
"As for circuit boards, sorry, they're long gone but schematic is attached for reference. Nearly all repairs go like this - an output tube shorts and takes out the resistor next to the test point. Replace both output tubes in that channel and the burnt cathode resistor and the amp is good as new. To play it safe for the tubes, bias to 250 or 300 instead of 400 like the manual says. The increase in distortion from running the tubes cooler is too small to hear."
My question is, since I am using a 5751 which I believe has less gain than 12AX7. IS it okay to bias at the level Anthem suggest (below)? I reconize I could ask them and probably will but 5751 is not one of their suggested 12AX7 replacement tubes.
Quote from Anthem
"As for circuit boards, sorry, they're long gone but schematic is attached for reference. Nearly all repairs go like this - an output tube shorts and takes out the resistor next to the test point. Replace both output tubes in that channel and the burnt cathode resistor and the amp is good as new. To play it safe for the tubes, bias to 250 or 300 instead of 400 like the manual says. The increase in distortion from running the tubes cooler is too small to hear."
Speakers: SDA-1C (most all the goodies)
Preamp: Joule Electra LA-150 MKII SE
Amp: Wright WPA 50-50 EAT KT88s
Analog: Marantz TT-15S1 MBS Glider SL| Wright WPP100C Amperex BB 6er5 and 7316 & WPM-100 SUT
Digital: Mac mini 2.3GHz dual-core i5 8g RAM 1.5 TB HDD Music Server Amarra (memory play) - USB - W4S DAC 2
Cables: Mits S3 IC and Spk cables| PS Audio PCs
Preamp: Joule Electra LA-150 MKII SE
Amp: Wright WPA 50-50 EAT KT88s
Analog: Marantz TT-15S1 MBS Glider SL| Wright WPP100C Amperex BB 6er5 and 7316 & WPM-100 SUT
Digital: Mac mini 2.3GHz dual-core i5 8g RAM 1.5 TB HDD Music Server Amarra (memory play) - USB - W4S DAC 2
Cables: Mits S3 IC and Spk cables| PS Audio PCs
Post edited by thsmith on
Comments
-
I guess I should have asked Anthem in the first place. Here is their response. Case closed.
Yes, the input gain has nothing to do with it.Speakers: SDA-1C (most all the goodies)
Preamp: Joule Electra LA-150 MKII SE
Amp: Wright WPA 50-50 EAT KT88s
Analog: Marantz TT-15S1 MBS Glider SL| Wright WPP100C Amperex BB 6er5 and 7316 & WPM-100 SUT
Digital: Mac mini 2.3GHz dual-core i5 8g RAM 1.5 TB HDD Music Server Amarra (memory play) - USB - W4S DAC 2
Cables: Mits S3 IC and Spk cables| PS Audio PCs -
Tracy,, when I had mine,, I used a 5751,,and biased the output tubes at .4,, ask Tom(trietz) about the output tubes,,IIRC, he is using the same ones that I had with the amp.JC approves....he told me so. (F-1 nut)
