Aye, once I've worked out the new 6C30pi input and driver stage.
Remember These?
- Cressy Snr
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#361 Re: Remember These?
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Cressy Snr
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#363 Re: Remember These?
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#364 Re: Remember These?
BTW, the 6H30pi was also used as the input/driver in the original Transcendent SE-OTL. I'll hazard a guess that the circuit for the stage will be the same in the Minibeast.
Sorry, I couldn't resist!
#365 Re: Remember These?
I used to get confused with the SE-OTL, which used parallel 6C19pi for its output.
Sorry, I couldn't resist!
- Cressy Snr
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#366 Re: Remember These?
There's always plenty of variety at Nick's
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#367 Re: Remember These?
Are you planning to try the 6H30pi on your breadboard Steve?
Sorry, I couldn't resist!
- Cressy Snr
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#368 Re: Remember These?
Not decided yet. I think the breadboard is coming very close to having served its purpose. It would involve a complete rebuild of the whole front end, including the heater wiring as the 5687 and its relatives has a different pinout to most of the rest of the 9 pin noval world.
I know how it sounds in the MiniBeast I built for Nigel, so there's probably not a great deal of point continuing the breadboard.
We'll see when they arrive next week.
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- izzy wizzy
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#369 Re: Remember These?
As it is completely different, wouldn't that be a good reason to bread board it? You'll probably end up with different feedback too as well as maybe different anode loads, bias resistors blah blah. May as well keep us entertained for a bit longerCressy Snr wrote: ↑Sun Jan 13, 2019 1:36 pmNot decided yet. I think the breadboard is coming very close to having served its purpose. It would involve a complete rebuild of the whole front end, including the heater wiring as the 5687 and its relatives has a different pinout to most of the rest of the 9 pin noval world.
I know how it sounds in the MiniBeast I built for Nigel, so there's probably not a great deal of point continuing the breadboard.
We'll see when they arrive next week.
Cheers,
Stephen
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#370 Re: Remember These?
That's what breadboards are for.Cressy Snr wrote: ↑Sun Jan 13, 2019 1:36 pmI know how it sounds in the MiniBeast I built for Nigel, so there's probably not a great deal of point continuing the breadboard.
The only thing necessary for the triumph of evil is for good men to do nothing.
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Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
#371 Re: Remember These?
The best part of using the 6H30 is that it ca be easily replaced by a 6H6p or 6H1p and more. My guess is, from listening to all 3 tubes in my sound systems (AR, SE OTL ), that a 6H30 might sound too sterile in a single output tube OTL. The 6H6p might sound warmer with more bass, the 6H1p a little more open in the upper mids with a little less punch in the bass than the 6H6p.The 6H6p needs double the heater current if tube rolling should be an option. But they are drop in replacements.
However, with some special attention to what the 6H30 needs in order to sound best it can be an exiting experience. With how much current and at which voltage the 6H30 is used will decide how good or boring it will sound. Lots of experimenting and listening.
However, with some special attention to what the 6H30 needs in order to sound best it can be an exiting experience. With how much current and at which voltage the 6H30 is used will decide how good or boring it will sound. Lots of experimenting and listening.
- Cressy Snr
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#372 Re: Remember These?
Did a bit of scoping early this morning. I thought I'd have another look after fitting the 5687s from Nick.
Also I put the idle current back to half an amp (520mA, up from 460mA) by putting in my original 2R4 programming resistors. I also sognificantly reduced the amount of feedback.
I was able to get to around 0.7 clean Watts before it started clipping.
Might not sound like much but it's remarkably good for a single tube without OPT, into 8 Ohms and it's more than it was putting out clean yesterday. We did, just about manage 1W, yesterday but the distortion was 10%. OK, some of that was down to duff drivers but hardly inspiring.
However with my 8 Ohm single driver speakers being 98dB efficient, the lack of power is not a handicap. Nevertheless, the case for 16 Ohm speakers is strong.
Also I put the idle current back to half an amp (520mA, up from 460mA) by putting in my original 2R4 programming resistors. I also sognificantly reduced the amount of feedback.
I was able to get to around 0.7 clean Watts before it started clipping.
Might not sound like much but it's remarkably good for a single tube without OPT, into 8 Ohms and it's more than it was putting out clean yesterday. We did, just about manage 1W, yesterday but the distortion was 10%. OK, some of that was down to duff drivers but hardly inspiring.
However with my 8 Ohm single driver speakers being 98dB efficient, the lack of power is not a handicap. Nevertheless, the case for 16 Ohm speakers is strong.
Last edited by Cressy Snr on Sun Jan 13, 2019 7:56 pm, edited 3 times in total.
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- Cressy Snr
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#373 Re: Remember These?
Oh and it was great to see Dave and Meredith, this afternoon. Some great music and great company.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Cressy Snr
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#374 Re: Remember These?
Thanks for the heads up on the 6H6P and 6H1P Wolfgang.Wolfgang wrote: ↑Sun Jan 13, 2019 3:01 pm The best part of using the 6H30 is that it ca be easily replaced by a 6H6p or 6H1p and more. My guess is, from listening to all 3 tubes in my sound systems (AR, SE OTL ), that a 6H30 might sound too sterile in a single output tube OTL. The 6H6p might sound warmer with more bass, the 6H1p a little more open in the upper mids with a little less punch in the bass than the 6H6p.The 6H6p needs double the heater current if tube rolling should be an option. But they are drop in replacements.
However, with some special attention to what the 6H30 needs in order to sound best it can be an exiting experience. With how much current and at which voltage the 6H30 is used will decide how good or boring it will sound. Lots of experimenting and listening.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
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#375 Re: Remember These?
Cheers Steve, it was a great way to spend a windy Sunday afternoon, thanks so much for your hospitality, and the tea, and the cheese and biscuits - all were delicious!Cressy Snr wrote: ↑Sun Jan 13, 2019 7:48 pm Oh and it was great to see Dave and Meredith, this afternoon. Some great music and great company.
It's quite amazing, hearing to what extent a room can be filled with three quarters of a watt. I rather envy you that amplifier, I definitely think you have a winning combination there. I'm wondering to myself how many 13E1's it would take to get to the equivalent of my 12xEL509 per side output stage. And whether it would cost more or less than buying 24 EL509's!!
Academic really as I'm rather committed at this point, although given that a second supplier has also entirely failed to deliver my order for the output valves that they promised me in November would be coming in 2 weeks - I'm starting to wonder if it might not actually be easier to get hold of the bloody 13E1's instead. They didn't respond to my chase-up email last week so I've just now read them the riot act and threatened action via PayPal unless they respond, so we'll see what happens.
End of thread hijack, as you were.
Deck: Garrard 301 - Audio Origami PU7 - NW Analogue DH3S
Phono: Pete Millett LR, Lundahl SUT, AMB σ22 PSU
Linestage: Bruno Putzeys Balanced Pre + Hans Polak relay mod, LCDuino control
Power amps: 300B PP 'Symmetric Reichert'
Speakers: FF225WK Big Mets
Phono: Pete Millett LR, Lundahl SUT, AMB σ22 PSU
Linestage: Bruno Putzeys Balanced Pre + Hans Polak relay mod, LCDuino control
Power amps: 300B PP 'Symmetric Reichert'
Speakers: FF225WK Big Mets