That makes since with the B+ around 180v. I would guess that -26v would be on the "biased hot" side of the equation. at 160-65 volts (which i'm getting) a little lower than 30 sounds best to me. Good info!!!!
Hey Dana, just FYI after monkeying with the bias again I think I'm happiest around -30v where I started. This time I went a little farther negative and tried -31, -33, and then back up to -26, -30. Also, I think I'm a little above 180v on B+, so with like 184v, I'm at -30v bias.
Thanks, really is a great sounding amp. I'm just finishing the front and back to the head cab, not sure if you know or not but the front planel sticks down about an 1/8" below the front of the chassis, so I ended up using some aluminum stock under the chassic to bring it up enough that I wasn't torquing down on the edge of the front plate.
That's great to hear. The front planel sticks down below the chassis because of the clips I use to install the chassis to the head box. If I make the front panel flush with the bottom of the chassis, I ended up with about a 1/16 inch gap. The chassis is actually lifted up off of the bottom of the head box because of the clips. Did you have the clips installed? Looking forward to some pics when you get it all done.
I did install the clips, but I wonder if mine are different than the Lowe's ones you use. The ones I bough were "Speed Nuts", and really only about 1/32 thick on the bottom flange. Maybe I should get the ones you use instead!
Thanks, and I'll post a pic when it's all complete. I still need to get that audio posted too.
skyclmbr wrote:
Hey Dana, just FYI after monkeying with the bias again I think I'm happiest around -30v where I started. This time I went a little farther negative and tried -31, -33, and then back up to -26, -30. Also, I think I'm a little above 180v on B+, so with like 184v, I'm at -30v bias.
Thanks, really is a great sounding amp. I'm just finishing the front and back to the head cab, not sure if you know or not but the front planel sticks down about an 1/8" below the front of the chassis, so I ended up using some aluminum stock under the chassic to bring it up enough that I wasn't torquing down on the edge of the front plate.
That's great to hear. The front planel sticks down below the chassis because of the clips I use to install the chassis to the head box. If I make the front panel flush with the bottom of the chassis, I ended up with about a 1/16 inch gap. The chassis is actually lifted up off of the bottom of the head box because of the clips. Did you have the clips installed? Looking forward to some pics when you get it all done.
I did install the clips, but I wonder if mine are different than the Lowe's ones you use. The ones I bough were "Speed Nuts", and really only about 1/32 thick on the bottom flange. Maybe I should get the ones you use instead!
Thanks, and I'll post a pic when it's all complete. I still need to get that audio posted too.
Bryan
It's hard to tell. It could be when they set up the brake to bend the chassis they got the bend on the wrong side of the line and made them a little shorter than my spec. I will measure the chassis I have here for the Lil Devil amps and then new Microplex chassis and see if I need to make an adjustment on the chassis on my next run. These are all things I want to know about so I make the changes to get them right.
UR12 wrote:
That's great to hear. The front planel sticks down below the chassis because of the clips I use to install the chassis to the head box. If I make the front panel flush with the bottom of the chassis, I ended up with about a 1/16 inch gap. The chassis is actually lifted up off of the bottom of the head box because of the clips. Did you have the clips installed? Looking forward to some pics when you get it all done.
I did install the clips, but I wonder if mine are different than the Lowe's ones you use. The ones I bough were "Speed Nuts", and really only about 1/32 thick on the bottom flange. Maybe I should get the ones you use instead!
Thanks, and I'll post a pic when it's all complete. I still need to get that audio posted too.
Bryan
It's hard to tell. It could be when they set up the brake to bend the chassis they got the bend on the wrong side of the line and made them a little shorter than my spec. I will measure the chassis I have here for the Lil Devil amps and then new Microplex chassis and see if I need to make an adjustment on the chassis on my next run. These are all things I want to know about so I make the changes to get them right.
Ok, sounds good. While we're talking about it, I had a little bit of trouble lining up the PCB holes with the PCB. I think I ended up having to enlarge a couple holes a bit to get them to line up. You may already know about it but just in case!
skyclmbr wrote:
Ok, sounds good. While we're talking about it, I had a little bit of trouble lining up the PCB holes with the PCB. I think I ended up having to enlarge a couple holes a bit to get them to line up. You may already know about it but just in case!
Yes it appears that the hole closest to the power control is off by just a little. I will have this fixed on the next run of chassis. You should be able to easily ream that hole out a little larger or oval to make it work.
I've been very busy with work (I am happy to report ), but I finally am getting started on my MicroPlex build. Can someone give me a heads-up on the PT primary color codes?
I've been very busy with work (I am happy to report ), but I finally am getting started on my MicroPlex build. Can someone give me a heads-up on the PT primary color codes?
Many thanks,
Lou
I asked Dana to send me the Lil Devil build instructions and went off of those, which worked fine. I'm not sure if they're posted anywhere but he should be able to send them to you. The only variation is the extra blue and white wires, which are for Japanese 100v connections and thus are not needed.
with the beginning of a new year it is time to get this project going.
I just ordered my parts from mouser except for the 10ohm 3w metal film resistor. it was on back order until 1/31 and I would either have to pay shipping twice or have the entire order held up until it was all in stock. I tried to find a comperable resistor but no luck. there is the slight chance I may already have one at home or maybe just maybe I can get one at radio shack or Fry's.
I'm waiting on that part as well I do have other things to finish up that should keep me busy though
dju wrote:with the beginning of a new year it is time to get this project going.
I just ordered my parts from mouser except for the 10ohm 3w metal film resistor. it was on back order until 1/31 and I would either have to pay shipping twice or have the entire order held up until it was all in stock. I tried to find a comperable resistor but no luck. there is the slight chance I may already have one at home or maybe just maybe I can get one at radio shack or Fry's.
myfoot wrote:I'm waiting on that part as well I do have other things to finish up that should keep me busy though
dju wrote:with the beginning of a new year it is time to get this project going.
I just ordered my parts from mouser except for the 10ohm 3w metal film resistor. it was on back order until 1/31 and I would either have to pay shipping twice or have the entire order held up until it was all in stock. I tried to find a comperable resistor but no luck. there is the slight chance I may already have one at home or maybe just maybe I can get one at radio shack or Fry's.
happy new year everybody!
dj
I found the 10ohm 3w resister at Digikey. it was more expensive but I used their cheapest shipping method which was around $2.28. With the price of gas that wasn't to bad to pay so I can get this thing assembled hopefully by mid January.
I found the 10ohm 3w resister at Digikey. it was more expensive but I used their cheapest shipping method which was around $2.28. With the price of gas that wasn't to bad to pay so I can get this thing assembled hopefully by mid January.
dj
I used this part from Mouser, I believe (which is in stock now):
594-5093NW10R00J
I had to find alternatives for several resistors and caps at the time I ordered all my parts. Also, I had to order a different channel switching switch that wasn't momentary on-off-on but on - off- on. I managed to get it all from Mouser though, after a couple of orders.
Got a PM about R32 being listed twice in the BOM. It should be a 470 ohm. Also been getting questions on the resistors for the PS board. I have included a pic of the populated PS board to try and help. Lou also found another small problem with the board in the PI area. I will address this shortly but I will test the fix before posting it here.
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hi guys,
I have most of my components mounted on my main board, yeah!
however I noticed that C33 is empty and I don't see it on the BOM which is what I have been using to populate my board with. Can anybody who has completed their board let me know what goes there?
), but I finally am getting started on my MicroPlex build. Can someone give me a heads-up on the PT primary color codes?
I do have other things to finish up that should keep me busy though 