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The Guiguang 300B have good bass ?

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A

aldovan

Member
Joined 2005
bayermar said:
Don't know what you refering to. I hear clear differences between different tubes (types and brands) if I drop them accidently and they hit the floor...
Click to expand...

Very funny, you should work as a clown, hehehehe ...:headbash:
I am testing the 300B's on a prototype and the circuit is the same.
With Shuguang the bass is weak and muddy.
With TJ are clear and deep ...
I want to know if anyone has tested the Guiguang 300B.
 
kevinkr

kevinkr

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Joined 2004
kta-hifi.net
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How about a schematic and some pictures instead? I really do not understand the fascination with youtube..

Note that I have heard differences between a lot of different 300B - however there is usually some measurable reason; higher distortion at a given power level, unusual distortion spectrum, a higher or lower rp than might be expected for the operating point of the particular tube, emission limited performance near the tube's maximum current rating. I have also encountered Chinese made 300B that had significant filament area exposed to the plate that was not within the confines of the grid structure; predictably these tubes could never be fully cut off and were also rather prone to run away at higher voltages as the tube warmed up with predictably catastrophic results.

Since comparatively few dht triode based SE amplifier designs use global negative feedback parametric variations between tubes do often result in audible and measurable differences in performance; some brands are much more consistent than others, and sample to sample variation can be rather significant depending on how consistent the manufacturer's process is and how effective QC is at catching defects. (if they even care)
 
L

luckythedog

Member
Joined 2009
kevinkr said:
Since comparatively few dht triode based SE amplifier designs use global negative feedback parametric variations between tubes do often result in audible and measurable differences in performance
Click to expand...
Yes. And a circuit is a circuit when all is said is done, what it looks like doesn't matter for test purposes, so long as it's safe and strays/grounding arrangement is reasonable IMO.
 
A

aldovan

Member
Joined 2005
kevinkr said:
How about a schematic and some pictures instead? I really do not understand the fascination with youtube..

Note that I have heard differences between a lot of different 300B - however there is usually some measurable reason; higher distortion at a given power level, unusual distortion spectrum, a higher or lower rp than might be expected for the operating point of the particular tube, emission limited performance near the tube's maximum current rating. I have also encountered Chinese made 300B that had significant filament area exposed to the plate that was not within the confines of the grid structure; predictably these tubes could never be fully cut off and were also rather prone to run away at higher voltages as the tube warmed up with predictably catastrophic results.

Since comparatively few dht triode based SE amplifier designs use global negative feedback parametric variations between tubes do often result in audible and measurable differences in performance; some brands are much more consistent than others, and sample to sample variation can be rather significant depending on how consistent the manufacturer's process is and how effective QC is at catching defects. (if they even care)
Click to expand...


The circuit do not is much important in my opinion, I can built several circuits with several results and my question is about if anyone know the Guiguang 300B tube.
But I like your explanation.
For me, the differences in materials and internal construction can change the result sound.
The CQ is a important factor, too.
 
A

aldovan

Member
Joined 2005
luckythedog said:
Yes. And a circuit is a circuit when all is said is done, what it looks like doesn't matter for test purposes, so long as it's safe and strays/grounding arrangement is reasonable IMO.
Click to expand...

Why you need the circuit ?
I do not like 12AU7, 12AX7 and 6922 tubes, for me this tubes sound poor.
But the peoples like and use this tubes and many modern amplifiers use this radio tubes...
But my question is...anyone use the Guiguang 300B ? Is good ? Is reliable ?
 
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