Because VT4c-211 too hot so I design a water cooling platform to fix Tube.
Second hand GE VT4C-211s.
Top view. The cooling heatsink is close rear board but no contact case.
Rear view. I open a window for water pipe through rear board.
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Hi!
This is completely unnecessary. Especially down there at the socket, a heatsink will not have much effect. The 211 is made for air cooling without the need for additional heatsinking.
Be careful with that aluminum plate fixed to the sockets! The screws in the ceramic which fix the connectors, carry high voltage and might be too close to that aluminum!
Thomas
This is completely unnecessary. Especially down there at the socket, a heatsink will not have much effect. The 211 is made for air cooling without the need for additional heatsinking.
Be careful with that aluminum plate fixed to the sockets! The screws in the ceramic which fix the connectors, carry high voltage and might be too close to that aluminum!
Thomas
Hi:
Thanks your remind!
I design a stick to fix platform.
This black Stick keep enough distance to isolate high voltage.
I also fix 211 cathod resistors on this platform.
After test looks pretty good.
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Hi!
That's not what I meant. There are screws going through the ceramic which fix the connectors on the socket. In some sockets these are insulated, in some not. They could be quite close to your aluminum heatsink. Better check that.
Seems like excessive heatsinking for a cathode resistor which dissipates only 5W.
Best regards
Thomas
That's not what I meant. There are screws going through the ceramic which fix the connectors on the socket. In some sockets these are insulated, in some not. They could be quite close to your aluminum heatsink. Better check that.
Seems like excessive heatsinking for a cathode resistor which dissipates only 5W.
Best regards
Thomas
Hi:
The screw is through caramic but still have about 5mm clearance to bottom.
About The cathode resistor ...because I use AC heater for VT4C and I remember cathode resistor is hot about 45 degree-C so I Buy 50W.
I have same experience on 300B cathode resistor too (same AC heater too) and cap. too close resistor the temp. cause cap. leak oil.
Your could check picture I also assembly a cooling fan on heat-sink because after 2 Hr the water pipe is hot too.
Maybe the heat is come from the socket of VT4C too.
ASter
Hi!
5mm clearance is quite tight. The plate does not only carry the full B+. If driven hard it can see voltage peaks of 2kV.
It is ok to overrate the wattage of resistors. I ususally use a factor of 5. It makes no difference to the dissipation of the cathode resistor if the 211 is AC heated or DC heated.
I use no extra heatsinking to sockets or resistors in my 211 amps and I drive the 211 at maqx plate dissipation.
Best regards
Thomas
5mm clearance is quite tight. The plate does not only carry the full B+. If driven hard it can see voltage peaks of 2kV.
It is ok to overrate the wattage of resistors. I ususally use a factor of 5. It makes no difference to the dissipation of the cathode resistor if the 211 is AC heated or DC heated.
I use no extra heatsinking to sockets or resistors in my 211 amps and I drive the 211 at maqx plate dissipation.
Best regards
Thomas
Hi:
I listen so many tube amplifier come out a result.....
I like the sound of Triode tube better than Pentode tube.
Btw still thanks your reply.
Aster
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..... i cheked different tube driver for 211 ....best result to my speaker (audio physics)was nos pentod-tetrod tubes...!!.. by test with piano ...receive this point...grate pentod -tetrod like f2a-el34-kt61 more focused and transparent than dht triod(like 45 or vt25..2a3) .....audio not use 6v6 for 211.the performers in the soundstage compared to those pentod -tetrod tubes ...dht drive are better.
for me 211 was not the first project ..Where can we get the experience for big 211 project .
power supplay is most important .gz34(uk) and gz32 (brimar).oil capacitors in 1250v.
in first stage ... ecc801 from telefunken one of The Best Choice for larger soundstage to my ears.
)compare :
5751 -mazda
e81cc -simens
ecc81 telefunken
6057-brimar
al2900-gec
ecc801 telefunken
12ax7 telefunken
...
An externally hosted image should be here but it was not working when we last tested it.
..... i cheked different tube driver for 211 ....best result to my speaker (audio physics)was nos pentod-tetrod tubes...!!.. by test with piano ...receive this point...grate pentod -tetrod like f2a-el34-kt61 more focused and transparent than dht triod(like 45 or vt25..2a3) .....audio not use 6v6 for 211.the performers in the soundstage compared to those pentod -tetrod tubes ...dht drive are better.
for me 211 was not the first project ..Where can we get the experience for big 211 project .
power supplay is most important .gz34(uk) and gz32 (brimar).oil capacitors in 1250v.
in first stage ... ecc801 from telefunken one of The Best Choice for larger soundstage to my ears.
compare :
5751 -mazda
e81cc -simens
ecc81 telefunken
6057-brimar
al2900-gec
ecc801 telefunken
12ax7 telefunken
...An externally hosted image should be here but it was not working when we last tested it.
Hi:
....by test with piano ...receive this point...grate pentod -tetrod like f2a-el34-kt61 more focused and transparent than dht triod(like 45 or vt25..2a3)...
For this feature ...Your tube amplifier must do something special design.
Circuit is transformer couple or cap. couple?
Pentod tube amplifier usually one tube grid need plate voltage feeb-back for normal working.
This circuit feature easy cause sound de-sensitivity.
ecc801 Gian factor u:60 This tube is good. but Ra about 11K too big.
ecc81 (12AT7) spec. is too.
I hope I one stage drive 211.
Thanks for yr reply.
ASter
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2 months before idecided ...
to test paralel 211 with pentod -tetrod drive tube.
2 mono block with 3 tube in each mono block.2x211+f2a.
and we used 12b4 in preamp . sound was different !!
12b4....f2a.....211x2.......speaker power suplay in sparet box :
power trans .....silicon bridg ........5ar4.......
so you can see the 211 is big sound its not first and simpel project .
it is final in hifi .poer se dht amp .and need to use Famous Tubes .no one small tube and high gain.simpel but ....
to test paralel 211 with pentod -tetrod drive tube.
2 mono block with 3 tube in each mono block.2x211+f2a.
and we used 12b4 in preamp . sound was different !!
12b4....f2a.....211x2.......speaker
power suplay in sparet box :power trans .....silicon bridg ........5ar4.......
so you can see the 211 is big sound
its not first and simpel project .it is final in hifi .poer se dht amp .and need to use Famous Tubes .no one small tube and high gain
.simpel but ....
the first project ecc801s+vt25+211 no pre amp !! gz32(brimar)+5r4(rca)
Hi:
Cool speaker! How much db sensitivity? about 92db?
Woofer look like 10'' E-ton speaker.
ASter
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2 months before idecided ...
to test paralel 211 with pentod -tetrod drive tube.
2 mono block with 3 tube in each mono block.2x211+f2a.
and we used 12b4 in preamp . sound was different !!
12b4....f2a.....211x2.......speaker
power trans .....silicon bridg ........5ar4.......
so you can see the 211 is big sound
it is final in hifi .poer se dht amp .and need to use Famous Tubes .no one small tube and high gain
Hi:
Your VT4C amplifier look like some kind hi-tech equipment...cool.
I got it and so Your feel SE DHT amp. is not good enough.
Your use 2x211 to build amp. that's meaning your amplifier is push-pull structure?
ASter
Mr211's Blog - Yahoo!?????--
Toy11 VT4C 211AMP -4
High voltage I design 2 times frequency boost and rectifier to 1600V(no load).
Two power balance chocks one is for 211 B+ another for GND.
Finish GE211 plate voltage connection with Teflon tub.
Finish OTP connection with Teflon tub too.
Insert GE211 tub prepare supply high voltage.
Connect AC power and audio signal.
Modify 6C45 & VT4C gride voltage to meet design.
Supply high voltage.
Measure GE211 plate voltage as design 1250V.
So far just finish one channel amplifier (This system is mono amp.) .
http://tw.myblog.yahoo.com/jw!9frLFy6fAkV0gBy_oZT_geG5fC24WQ--
High voltage I design 2 times frequency boost and rectifier to 1600V(no load).
Two power balance chocks one is for 211 B+ another for GND.
Finish GE211 plate voltage connection with Teflon tub.
Finish OTP connection with Teflon tub too.
Insert GE211 tub prepare supply high voltage.
Connect AC power and audio signal.
Modify 6C45 & VT4C gride voltage to meet design.
Supply high voltage.
Measure GE211 plate voltage as design 1250V.
So far just finish one channel amplifier (This system is mono amp.) .
http://tw.myblog.yahoo.com/jw!9frLFy6fAkV0gBy_oZT_geG5fC24WQ--
Hi Aster,
Your meter measures VT4C/211 anode at 1265V? It's already
higher than 1250V maximum.Why do you need that much power when you
are using high efficiency speaker at 92db? More power gives more distortion.
Another thing is when you want to use shuquang or other chinese
tube they may not be able to last long or survive that high anode voltage.
Why not set it at 1000V - 1100V?
Are you using switchmode supply or normal voltage doubler for 211/VT4C
anode? So how is the sound of your amp? singa
Your meter measures VT4C/211 anode at 1265V? It's already
higher than 1250V maximum.Why do you need that much power when you
are using high efficiency speaker at 92db? More power gives more distortion.
Another thing is when you want to use shuquang or other chinese
tube they may not be able to last long or survive that high anode voltage.
Why not set it at 1000V - 1100V?
Are you using switchmode supply or normal voltage doubler for 211/VT4C
anode? So how is the sound of your amp?
singa
Hi Aster,
Your meter measures VT4C/211 anode at 1265V? It's already
higher than 1250V maximum.Why do you need that much power when you
are using high efficiency speaker at 92db? More power gives more distortion.
Another thing is when you want to use shuquang or other chinese
tube they may not be able to last long or survive that high anode voltage.
Why not set it at 1000V - 1100V?
Are you using switchmode supply or normal voltage doubler for 211/VT4C
anode? So how is the sound of your amp?
Hi Singa:
I designed to setup anode voltage in 1250V.
That's GE VT-4C Max. anode operation voltage just for better high freq.
performance.
Because I had ever listen over 5 set SE 211 amplifier ...hi-freq perferance all feel not good.
High Freq. Too rough and I will do anything to struggle for more hi-freq clear body line and air feeling.
In Taiwan someboy say 211 voltage more higher more beautiful but just no one do it ...basically I do'tn see any paper post it.
So I want take guts to try it.
I had ever read Japan Kodon's master say he choice GE VT-4C only ...me too and I believing GE VT-4C have good capability.
I don't concern China 211 Tube if the 300B I will choice it reason is got good C/P.
I just use one rectfier tube Mullar GZ37 take 2-times boost to 1600V(no VT-4C insert). 5U4G could do that's too but low-freq. performance not good.
After insert VT4-C anode voltage will pull down to about 1244~1260V.
Another reason is my Mono box too small no place to put in two rectfier tube.
About sound I always to benchmark with sound of 300B(another DIY amplifier).
My audio gear fans say it's totally different VT-4C's sound of images.
Aster
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