Metropoulos Forum

here's some info on filtering: http://marstran.com/Historic%20Data%20Base.htm

i have a question.

when doing the testing, is it ok to run the amp on play mode with the preamp tubes in but with out the speaker load and the el34 tubes?
it seems to me that it didnt mention the load on preaamp only with no power tubes. the insert a load is mentioned on the part where to install th epower tubes.

Sure. You can go from standby to "operate" with no speaker load when you don't have any power tubes installed. If you put in power tubes (feeding the OT with pure tube goodness), then you need a speaker load on the other side of the OT to deal with that power.

In the instructions it says, "Power off and install (2) EL34 output tubes. Attach a speaker and power the amp on. . . " Seemed clear enough to me, but there are a lot of instructions to read, and people read them different ways. But to be sure, go right ahead. Just be sure to have a load attached if you have power tubes installed.

thousandshirts wrote:Sure. You can go from standby to "operate" with no speaker load when you don't have any power tubes installed. If you put in power tubes (feeding the OT with pure tube goodness), then you need a speaker load on the other side of the OT to deal with that power.

In the instructions it says, "Power off and install (2) EL34 output tubes. Attach a speaker and power the amp on. . . " Seemed clear enough to me, but there are a lot of instructions to read, and people read them different ways. But to be sure, go right ahead. Just be sure to have a load attached if you have power tubes installed.

yeah i know that part and have read it over and over . it just confused me why it was said so ONLY in the power section and not in the pre section. thinking of a double open curcuit. but oh wel now you confirmed it8)

Reading that makes me consider buying a kit. But, Plexi style, or metal-paneled. Hmm...

capelton wrote:Reading that makes me consider buying a kit. But, Plexi style, or metal-paneled. Hmm...

well? what are you waitin for?

capelton wrote:Reading that makes me consider buying a kit. But, Plexi style, or metal-paneled. Hmm...

You can build your kit and switch back and forth between Plexi or Metal Panel by changing just a few components. $25 of parts at the outside, if you buy a nice filter cap for the 33/33 or 50/50.

http://forum.metroamp.com/viewtopic.php ... 6&start=40" onclick="window.open(this.href);return false;

Is a 50/50 axial cap available that can fit directly on the board "down below" style?

Minor stuff here - just from the parts list.

Sozo .68uF@400v - i think should be .68uF@160v
25k Audio taper pot - i think should be 25k Linear pot

Also listed is a 220uF electrolytic @ 50v.
This doesn't seem to be available from the parts store and i assume 25v version is suitable ?

Other than that - AWESOME.
I've order my bits - can't wait to get started.
Thanks George for the quick response to my emails !!

Wayne.

Wayne wrote:Minor stuff here - just from the parts list.

Sozo .68uF@400v - i think should be .68uF@160v
25k Audio taper pot - i think should be 25k Linear pot

Also listed is a 220uF electrolytic @ 50v.
This doesn't seem to be available from the parts store and i assume 25v version is suitable ?

Other than that - AWESOME.
I've order my bits - can't wait to get started.
Thanks George for the quick response to my emails !!

Wayne.

yes 160v and 25 is fine. there's about 1v on v1a k and v1b k

Instructions updated to V 1.2 Sept 2009.

Fixed various typos and added text.

Notes for voltage chart and standby switch voltage measurement added.



george

Great instructions,

need to add instructions about wiring the board to 1986 Bass specs, to omit the wire from the board that would go to to V-1 pin 8, and place jumper between pins 3 and 8.

Some of us are noobs.

see thread on this here:
http://forum.metroamp.com/viewtopic.php ... 84#p279584" onclick="window.open(this.href);return false;

Isn't the one with the split cathode (1987) more of a lead config and the 1986 (common cathode) more of a bass type?

VelvetGeorge wrote:Instructions updated to V 1.2 Sept 2009.

Fixed various typos and added text.

Notes for voltage chart and standby switch voltage measurement added.



george

Thanks George...

Can someone please tell me where the shorter choke wire is connected?? I see the wire that is twisted together and connected to the upper right corner of the board, but I cant find anything about where the OTHER wire from the choke wire attaches.

grindliner wrote:Some of us are noobs.

What he said...