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Got my SFDR last night need advice on...

9/2/1999 6:40 PM
pHiL	Got my SFDR last night need advice on... tube placement. The previous owner very carefully removed the tubes before shipping, wrapping them in bubble wrap and put them in the back of the amp. My problem is this. It appears that some of the preamp / vib/ rev / driver tubes have been substituted so I haven't fire it up until I know which position they should most like go. To pin it down mainly the Philips 12AX7A/7025A(what is it really?) and the Siemans ECC81. Enter Ampage to the rescue! The tube chart reads: 5U4GB - 6V6 - 6V6 - 12AT7 - 12AX7 - 7025 - 12AT7 - 7025 - 7025 With the tubes that were supplied I'm guessing they should be positioned as follows. I'm also indicating mfr. 5U4GB(RCA) - 6V6(SYL) - 6V6(SYL) - 12AT7(RCA) - 12AX7(JOLIDA) - 12AX7A/7025A(PHLPS) - ECC81(SMNS) - 7025(RCA) - 7025(RCA) I'm planning on taking this into my amp tech next week but I would still like to be able to fire it up and get the best out of it if possible with the existing tubes without damaging anything. Any suggestions? Thanks, pHiL

9/2/1999 6:40 PM

pHiL

Got my SFDR last night need advice on...

tube placement.

The previous owner very carefully removed the tubes before shipping, wrapping them in bubble wrap and put them in the back of the amp.

My problem is this. It appears that some of the preamp / vib/ rev / driver tubes have been substituted so I haven't fire it up until I know which position they should most like go. To pin it down mainly the Philips 12AX7A/7025A(what is it really?) and the Siemans ECC81.

Enter Ampage to the rescue!

The tube chart reads:

5U4GB - 6V6 - 6V6 - 12AT7 - 12AX7 - 7025 - 12AT7 - 7025 - 7025

With the tubes that were supplied I'm guessing they should be positioned as follows. I'm also indicating mfr.

5U4GB(RCA) - 6V6(SYL) - 6V6(SYL) - 12AT7(RCA) - 12AX7(JOLIDA) - 12AX7A/7025A(PHLPS) - ECC81(SMNS) - 7025(RCA) - 7025(RCA)

I'm planning on taking this into my amp tech next week but I would still like to be able to fire it up and get the best out of it if possible with the existing tubes without damaging anything.

Any suggestions?

Thanks,

pHiL

Replies:

Troy Phil: Sounds like you've got it ri... -- 9/2/1999 6:48 PM