Yes, a 6x5gt is coming in final build, now i have the similar 6x4- R (russian)
Yes. Now i can simulate
look about halfway down the page here
The ps-4 psu is a nifty circuit. You can configure the heaters as dc with a voltage doubler so you could then wire the heaters in series so each tube sees half of the doubled voltage. I have a couple of his psu boards and they work great. I like the way broskie explains the thinking behind it. I have learned a lot reading his blog.
The ps-4 psu is a nifty circuit. You can configure the heaters as dc with a voltage doubler so you could then wire the heaters in series so each tube sees half of the doubled voltage. I have a couple of his psu boards and they work great. I like the way broskie explains the thinking behind it. I have learned a lot reading his blog.
THE Truck is gone!!
with 40 film+choke+47+1.1K+47+1,1K+40 film, - hum is very much gone.
I will test with higher capacitance on 3rd place when it comes in a few dayes.
I've only some minor hum higher up (don't hear it with only my bass amp) but when my delay clicks on my KT88 amp that small hum comes on.
This is the best so far.
I measured voltage B+ to 265V
and cathode is about 5mA after changing cathoderes to 330ohms.
I replaced the old res (1% metal) to Kiwame on gridstopper and cathode) and that probably did something to SQ cuz now it's very high quality.
VERY open, dynamic and CLEAN. Drums sound like drums, can almost smell the skin
Yeah, this is what i was looking for. Though, it doesn't sound much like "tubes" actually. It doesn't sound much at all. It just is very transparent to my ears.
with 40 film+choke+47+1.1K+47+1,1K+40 film, - hum is very much gone.
I will test with higher capacitance on 3rd place when it comes in a few dayes.
I've only some minor hum higher up (don't hear it with only my bass amp) but when my delay clicks on my KT88 amp that small hum comes on.
This is the best so far.
I measured voltage B+ to 265V
and cathode is about 5mA after changing cathoderes to 330ohms.
I replaced the old res (1% metal) to Kiwame on gridstopper and cathode) and that probably did something to SQ cuz now it's very high quality.
VERY open, dynamic and CLEAN. Drums sound like drums, can almost smell the skin
Yeah, this is what i was looking for. Though, it doesn't sound much like "tubes" actually. It doesn't sound much at all. It just is very transparent to my ears.
I now know strongly believe that the PSU is the heart and soul of tubes cuz now there is something "special" in the midrange i missed before..
When i listen to Elvis, you're always on my mind or Mark Knopfler-Get lucky or Allan Taylor - Colour to the moon (for example), it really touches my soul on a level i never heard in my system before.
Thanks guys.
When i listen to Elvis, you're always on my mind or Mark Knopfler-Get lucky or Allan Taylor - Colour to the moon (for example), it really touches my soul on a level i never heard in my system before.
Thanks guys.
Glad to hear it worked out.
Now going back and paying attention to star grounding should eliminate the last of the hum you have lingering about. Its most important to not have your small signal (input RCA and grid stoppers) tied to anything high power ie your PSU caps. Tie all your small signal grounds together and then take a thin wire to your high current grounds in your power supply. Finally a big wire straight from your high current ground to your socket safety ground.
Great to hear when a good project comes together and you learn something along the way.
Shoog
Now going back and paying attention to star grounding should eliminate the last of the hum you have lingering about. Its most important to not have your small signal (input RCA and grid stoppers) tied to anything high power ie your PSU caps. Tie all your small signal grounds together and then take a thin wire to your high current grounds in your power supply. Finally a big wire straight from your high current ground to your socket safety ground.
Great to hear when a good project comes together and you learn something along the way.
Shoog
Maybe i'm little behind hehe
Ok. Is it normal to ground low level signal (with pot) to ground at same point as cap-? I've read somewhere signalground should not be 'together' with chassie/groundpoint/cap minus??! I saw in my Yaqin mc100 that signalground was together with all other groundpoints and in my ears it's hum/buzz free even with AC heaters so that's why i used same teqnicue here.
When i do my final build of this preamp i will try to do better and also layout.
Ok, maybe easier like this: where should ground from RCA input/output go for the best noisefree sound?
Ok. Is it normal to ground low level signal (with pot) to ground at same point as cap-? I've read somewhere signalground should not be 'together' with chassie/groundpoint/cap minus??! I saw in my Yaqin mc100 that signalground was together with all other groundpoints and in my ears it's hum/buzz free even with AC heaters so that's why i used same teqnicue here.
When i do my final build of this preamp i will try to do better and also layout.
Ok, maybe easier like this: where should ground from RCA input/output go for the best noisefree sound?
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Maybe i'm little behind hehe
Ok. Is it normal to ground low level signal (with pot) to ground at same point as cap-? I've read somewhere signalground should not be 'together' with chassie/groundpoint/cap minus??! I saw in my Yaqin mc100 that signalground was together with all other groundpoints and in my ears it's hum/buzz free even with AC heaters so that's why i used same teqnicue here.
When i do my final build of this preamp i will try to do better and also layout.
Ok, maybe easier like this: where should ground from RCA input/output go for the best noisefree sound?
A single ground point has generally been the most trouble free approach for me.
Creating a small signal ground and then a high power ground and linking them with a small wire should work - but could create a ground loop through the case which would be hard to predict. This approach has never failed for me just so long as the current "gradient" potential is down from the small signal to the high current reference. This usually involves having the small signal ground isolated from the case.
The RCA ground would go to the small signal ground - but there is a potential that this could lead to loops between different hifi components at slightly different ground potentials.
Stick with what you have now since it is working well.
Shoog
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When i came home from work today i got little pissed off about this "buzz/hum" or whatever we might call it and took out my transformer from the case and suddenly it's almost dead quiet
I had to take it away about 8 inches /20cm from everything (especially low level signal). So i'll guess i have to put it outside my case till i've done final mounting (also order a transformer cover)
By the way, i've been looking for that on ebay and the chinese people want like 50 bucks (35e) with shipment. Seems a bit high for such a small "aluminiumbox" made only from two pieces.
Do you know any other place (in europe preferably) that sell transformer cover for a good price?
I've seen aluminium and iron (magnetic?), which one is better? I think it looks better with aluminium but if the other one shields better then ofcourse i'll have that.
I had to take it away about 8 inches /20cm from everything (especially low level signal). So i'll guess i have to put it outside my case till i've done final mounting (also order a transformer cover)
By the way, i've been looking for that on ebay and the chinese people want like 50 bucks (35e) with shipment. Seems a bit high for such a small "aluminiumbox" made only from two pieces.
Do you know any other place (in europe preferably) that sell transformer cover for a good price?
I've seen aluminium and iron (magnetic?), which one is better? I think it looks better with aluminium but if the other one shields better then ofcourse i'll have that.
most of them are. Especially the 6.3V out and 230-0-230.
But the transformer are very close to signal /input/output.
I bent a piece of aluminium i had laying around (cover almost whole transformer) but it didn't help at all. ONLY if i put it in standing position! but then the lid wont fit anymore. One opening on transformer pointing straight back vertical and one to the front) then it's ok. No hum.
But the transformer are very close to signal /input/output.
I bent a piece of aluminium i had laying around (cover almost whole transformer) but it didn't help at all. ONLY if i put it in standing position! but then the lid wont fit anymore. One opening on transformer pointing straight back vertical and one to the front) then it's ok. No hum.
Yeah this is rated to 30VA and i've measured consumption to 17-18W (but that was before (original state) and it gets pretty hot.
BUT it's chinese made so it can probably be whatever, all rating is in chinese so i have to trust the ebay-seller (Along1986030)
I actually have copper-tape here
Worth a try then? You mean on top of the winding? How many layers?
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