andrea, we did a group buy at http://www.hi-end.on9mart.com/cart/hi_body_3.html in hongkong. This seller has sells us a lot before in the past. Just mail him and ask for the price.
I also like your Class D test. And the link to the hififever forum about the hybrid UCD with was my thread. Nowadays it looks like this.
Mush, the plate voltage was between 880 and 905 Volt.
Ronny
I also like your Class D test. And the link to the hififever forum about the hybrid UCD with was my thread. Nowadays it looks like this.
An externally hosted image should be here but it was not working when we last tested it.
Mush, the plate voltage was between 880 and 905 Volt.
An externally hosted image should be here but it was not working when we last tested it.
Ronny
What about using a C3g as a driver?I read in the link that when using 6C45 the inputsensitivity would be 1,5vRMS,what will it be with C3g?
Koifarm
Have you heard the smooth plate Shuguang 813? I'm having trouble finding the finned version and would like to know if the smooth plate is a good alternative.
Thanks
Have you heard the smooth plate Shuguang 813? I'm having trouble finding the finned version and would like to know if the smooth plate is a good alternative.
Thanks
Yes, C3g as a driver is possible but I don't think this is better
C3g
Va = 200v
Ia = 17mA max
Pa=3.4w
Ri=2300ohm
Rk=180ohm min value
u=40
D3a
Va = 160v
Ia = 20-24mA
Pa=3.84w
Ri=1.9ohm
Rk=82-100ohm
u=77
The distortion could be lower with C3g because this work at 200v instead of 160-170v but the current must be limited for the lower power dissipated.
In my case the D3a have the min voltage gain to drive this amp. with my new Phono End preampl.
C3g
Va = 200v
Ia = 17mA max
Pa=3.4w
Ri=2300ohm
Rk=180ohm min value
u=40
D3a
Va = 160v
Ia = 20-24mA
Pa=3.84w
Ri=1.9ohm
Rk=82-100ohm
u=77
The distortion could be lower with C3g because this work at 200v instead of 160-170v but the current must be limited for the lower power dissipated.
In my case the D3a have the min voltage gain to drive this amp. with my new Phono End preampl.
Koifarm
Have you heard the smooth plate Shuguang 813? I'm having trouble finding the finned version and would like to know if the smooth plate is a good alternative.
Thanks
Mush, i did not like the smooth plate, there is a big difference. The shuguang 813 smoothplate is just like the RCA and GE. A bit slow and fluid. The shuguang FU13 ribbed plate is like the curtains are now open, before with the other tubes they were closed. So a big difference in all the aspects.
In a previous reply i placed a link to the supplier of my spare tubes, just send him a email and ask for the tubes and the price.
Ronny
From: <sales@on9mart.com>
To: "Andrea Ciuffoli" <webmaster@audiodesignguide.com>
Sent: Wednesday, August 12, 2009 8:23 AM
Subject: Re: info
> Hello Andrea,
>
> Thank you for your email, we sell FU13 tubes for GBP42 each, thank you.
>
> Best regards,
> On9mart.com
To: "Andrea Ciuffoli" <webmaster@audiodesignguide.com>
Sent: Wednesday, August 12, 2009 8:23 AM
Subject: Re: info
> Hello Andrea,
>
> Thank you for your email, we sell FU13 tubes for GBP42 each, thank you.
>
> Best regards,
> On9mart.com
Probably this is a better source:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=310143510083&ssPageName=ADME:X:RTQ:GB:1123
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=310143510083&ssPageName=ADME:X:RTQ:GB:1123
Probably this is a better source:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=310143510083&ssPageName=ADME:X:RTQ:GB:1123
These are not the required ribbed plates but the smooth plates. They have a very poor sound.
An externally hosted image should be here but it was not working when we last tested it.
Ribbed plates ( above).
Smooth plates ( under ).
An externally hosted image should be here but it was not working when we last tested it.
Onlinemart just wrote back and want $120 per pair and $200 per quad, ship cost included, to the US. They did not confirm if the 813/Fu13 they had were finned. That's sort of steep. We're getting into 845 territory.
Are the finned Fu13 that much better than the US 813, copper GM70 or Shuguang 845B?
Are the finned Fu13 that much better than the US 813, copper GM70 or Shuguang 845B?
Are the finned Fu13 that much better than the US 813, copper GM70 or Shuguang 845B?
We did some testing with the FU13 ribbed and smooth plates, RCA 813 and the GE 813. And the most of the 20 people like the ribbed( finned ) FU13 the most.
About the GM70 and 845B i have not listen to them.
Ronny
I don't have ear the 813 Ribbed plates.
The GM70 if compared to the 813 RCA have more details but the sound is less pleasant and fatiguing.
Some my friends prefer the GM70 and others the 813 RCA.
The 845B cannot be compare with these other high voltage gain tubes because the 845B will be used with a different drive stage so many other parameters will change.
The sound quality of my 845 two stage amplifier as been compared to the my GM70 two stage amplifier in a recent session in my house with 4 persons with a lot of experience in sound reprodution and the result for all was good with both.
The GM70 if compared to the 813 RCA have more details but the sound is less pleasant and fatiguing.
Some my friends prefer the GM70 and others the 813 RCA.
The 845B cannot be compare with these other high voltage gain tubes because the 845B will be used with a different drive stage so many other parameters will change.
The sound quality of my 845 two stage amplifier as been compared to the my GM70 two stage amplifier in a recent session in my house with 4 persons with a lot of experience in sound reprodution and the result for all was good with both.
Ribbed or not, I do not think it is the construction in itself, that makes the difference, more probably voltage/bias.
Several Audioromy owners I spoke to, prefer RCA/NU/..over the ribbed ones.
Arne K
Several Audioromy owners I spoke to, prefer RCA/NU/..over the ribbed ones.
Arne K
What is the optimum load for GM70?
I have a Lundahl trafo I can chose 6,5Kohm and 11kohm..
11K is better but you need high plate voltage (1KV or more).
In my project I want a good damping factor (low Rout) to drive any loudspeakers without coloration so I always use high value 10k and 11k for the 845-GM70-813-SV572-3 tubes.
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