DSL40C ?

motoputz

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Should have most of my tubes this afternoon it looks like. I've got the amp sitting apart and waiting to be biased. It's really clean inside. I took a magnifying glass and looked over the amp, the soldering looks solid, at least from a quick glance with nothing jumping out as out of place. Anything I should look for or at while it's open?
Could someone explain what each of the preamp tubes, V!, V2, V3, V4 are for on this amp?
Any pre amp tube recipes for the dsl40c? I've started collecting differant tube arrangements to try
thanks for the info, I appreciate it all
 

motoputz

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Got my tubes, burned in the EL34's for 28hrs, for no particuliar reason it just worked out this way
My power is 122V out the wall.
I decided to do an initial bias before burn in and reading the plate voltage. I measured "32.1mA" before tube burn in, "31.7mA" after 28 hrs. of burn in. I burned in the tubes with a bias of 32mA.
After burn in;
I measured plate voltage and measured 472VDC on both tubes
I went to Weber Bias Calc. to figure out the bias.
Weber has an A/B amp with EL34's at 472 VDC bias at 37mA
I biased to 36mA, mainly because it was easier to keep both tubes steady at 36mA than 37mA for some reason. At the 37mA range I got a lot of variation 36.7 - 37.6 it wouldn't settle.(operator error obviously!)
- cut C19 - not sure I'm hearing any differance? time will tell
- V1 12AX7 EHG
-V2 5751
-V3 12AT7WA
-V4 12AU7
The 12AU7 had the biggest impact, for me, on the overall sound. It's still got a lot of chunk left. I have some other tubes coming to experiment with. More on that to come

What pre amp tubes are you using?
 

motoputz

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I had a light bulb moment last night while playing. I've been running two amps though an ABY box and getting a horrible ground loop, grounding issue that was impossible to get rid of.
I turned "off" my lights and SILENCE?
My lights in my room are all LED with a dimmer switch on the same circuit as my outlets.
I'm fairly certain now that the LED's with a dimmer switch have been causing the bad power problem I've had in my practice room. My power conditioner did very little, if anything to rectify the issue
I'm switching back to incandesent fixtures
 

ken361

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I wouldn't go by Weber on these I use to when my tech said that 32 was best I tried high as 36 it got fuzzy some and lost it's tightness. Preamp distortion doesn't need to be high.
 

motoputz

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I wouldn't go by Weber on these I use to when my tech said that 32 was best I tried high as 36 it got fuzzy some and lost it's tightness. Preamp distortion doesn't need to be high.
I think the Weber calc give a number to shoot for, a safe zone. Just by what I've read online the sweet spots are between 32 - 38. I've since rebiased to "32". I like much more better
 

steveb63

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Lmfao 😄 🤣 💀 who made this??? It's perfection 😍
I honestly don't know Lol.

Someone D.M.'d me it when I bought my DSL 40c about three or four years ago.

I have it saved for just these circumstances, and agree with everyone- friggin' hilarious.

" Do you want to look like a fuxin' purple dinosaur onstage?" I laugh every time I see that part.

Really happy it was enjoyed, and no one took me too serious, I also own a DSL 20H, so I'm just havin' fun with it.
 

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