New Build Poll: 5D3 Deluxe or 1x12 6V6 tweed Bassman?

5D3 or 6V6 Bassman?

  • 5D3 Deluxe

    Votes: 11 39.3%

  • 6V6 tweed Bassman

    Votes: 17 60.7%
  • Total voters
    28
gabasa

gabasa

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schmee said:
Those pre tubes can be pretty frustrating for sure. I dont have an answer for you, I'd go with 9 pin pre tubes....
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Yeah, perhaps 12AY7/12AX7 tubes all around would be safer. I just don't know if this would mess with the overall character of the build because I haven't played octal preamp tubes in decades! I've certainly never compared octal to noval side by side.
 
schmee

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gabasa said:
Yeah, perhaps 12AY7/12AX7 tubes all around would be safer. I just don't know if this would mess with the overall character of the build because I haven't played octal preamp tubes in decades! I've certainly never compared octal to noval side by side.
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I haven't AB'd them either. I have had some old school amps with them though. There is a certain tonality to the octals. Almost like a hint of dirt along with a 50's hifi saturation type of thing. Hard to describe.
I just gave up on the octal pre tube thing playing in a band mix, and dealing with the microphonics was a PITA. I was down to buying the metal cased ones to try to improve my luck. I may have a couple tubes here.
Is anyone making a modern 6SN7, 6SC7 etc??
 
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gabasa

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schmee said:
I haven't AB'd them either. I have had some old school amps with them though. There is a certain tonality to the novals. Almost like a hint of dirt along with a 50's hifi saturation type of thing. Hard to describe.
I just gave up on the noval thing in a band mix, and dealing with the microphonics was a PITA. I was down to buying the metal cased ones to try to improve my luck. I may have a couple tubes here.
Is anyone making a modern 6SN7, 6SC7 etc??
Click to expand...
Do you mean octals?
 
printer2

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schmee said:
I haven't AB'd them either. I have had some old school amps with them though. There is a certain tonality to the octals. Almost like a hint of dirt along with a 50's hifi saturation type of thing. Hard to describe.
I just gave up on the octal pre tube thing playing in a band mix, and dealing with the microphonics was a PITA. I was down to buying the metal cased ones to try to improve my luck. I may have a couple tubes here.
Is anyone making a modern 6SN7, 6SC7 etc??
Click to expand...
Get your wallet out.

Electro-Harmonix 6SN7 Preamp Tube | 6SN7 EH | Electro-Harmonix

Electro-Harmonix tubes are all new designs and are of excellent quality. Many OEMs use relabeled Electro-Harmonix vacuum tubes in their amplifiers. If you want great sounding tubes at a very reasonable price, then Electro-Harmonix tubes should be on your l | 6SN7 EH
shop.ehx.com

Sovtek 6SC7 Preamp Tube | 6SC7 | Electro-Harmonix

Sovtek tubes are quite simply the absolute best. We design and manufacture our tubes, engineered for demanding high fidelity, reliability and overall warmth. Be sure to insist on genuine Sovtek vacuum tubes the next time you retube -- you'll be getting the | 6SC7
shop.ehx.com

Could always use a 9-pin up front and the octals after that in order to reduce microphonics.
 
gabasa

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Hmm...

Maybe I should use 5751 tubes in place of the 6SC7; at least they have the same gain factor.
 
NTC

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Sound wise, the octals have something that 9 pin dual triodes don't. They are worth the (probably head-pounding) effort.
 
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One build I used two 6SL7 did hum. Perhaps tubes were bit bad but I did not have replacements. PT had also 12,6V output so I bridge rectified it, filtered and regulated using TO-220 chip and then the hum became significantly quieter. I can't say it is a norm but quite often HiFi builds which use Octals seem to have DC filaments. Rectifying 6,3VAC might make DC bit low but obviously using Schottky diodes DC can come bit over 6VDC.

I have read that 12_ _7 tubes filaments are wound opposite direction (bifilar might be the method) and then feeding 6,3VAC cancel filament hum. But 6_ _7 tubes do not have opposite wound filaments. 12_ _7 were developed when cars battery was decided to change 6V to 12V and then they were and still are possible to use on more applications using filaments parallel or series.
 
gabasa

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I was able to get three of these chassis. One is for a friend so the other two are for my own builds. I'm thinking an early, octal Pro and a noval Super. The four inputs in the chassis aren't inline, but it doesn't really matter. I can easily fit the circuits in. Between the tone knob and the pilot light, there is some room on the chassis; I might silkscreen something in that spot if I'm brave enough. Here's what they look like:

Chassis 1.jpg
Chassis 2.jpg
Chassis 3.jpg
 
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NTC

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Where did you get these? What is the length? It looks 5E5/5F6/5E7 size.
 
gabasa

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NTC said:
Where did you get these? What is the length? It looks 5E5/5F6/5E7 size.
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It is the correct size for those amps. Someone custom ordered a handful of these chassis from Mojotone a while ago and I think that these were just leftovers. If anything, I think that the possibility of custom, group orders from Mojotone by us here would be a cool idea once in a while.
 
gabasa

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I found this video comparing a 1953 6SC7 Super, a 1954 12AX7 Super and a 1959 narrow panel Super.
It's pretty informative and educational, just wondering what your opinions are.



However, this one has 12AX7s and it sounds great:





Sorry to venture so far off topic, it's actually how the conversation progressed.
 
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screefer

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The first video was enlightening.

The '53 is a grid leak bias 5C4?
1675700996838.png

the '54 is a cathode bias 5D4?
1675701107691.png
 
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