• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tube preamp

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
Byronkoeder

Byronkoeder

Member
Joined 2013

Attachments

  • DSCN1067.jpg
    DSCN1067.jpg
    1 MB · Views: 597
Last edited:
W

wdecho

Member
Joined 2014
At the present time I am using a very simple tube pre with a lot of 2nd harmonic. I am in the process of build a push pull tube pre that is "cleaner" to compare. I might prefer the more 2nd harmonic with SS amps. My plan is to use the PP tube pre with tube amps that require a pre to keep everything all tube.
 
Byronkoeder

Byronkoeder

Member
Joined 2013
Bigun said:
The pedantic folk call Class AB. Anyhow, dont see why you cant use it with a tube pre. The sound contribution of the pre will depend on its design, they can be very neutral, or you could add a bit of 'flavour' which is what I think you have in mind
Click to expand...

Yes the warmer flavor is what I had in mind but I watched a Bob Carver video with him explaining how a tube amp works . He explained that they get sound from the reflective sound wave bouncing off the speaker facing wall back to push the cone inward causing the coils to move creating a charge that is sent back to the tube via return line . this he said gives you that warm flavor sound we all love but An A/B solid state Chip amp cancels this effect not allowing the speaker cone to be effected by reflecting sound waves . So it makes think the A/B amp being the last in the chain would keep the tube preamp from giving you that warm tone. Am I wrong in assuming this ?
 
Byronkoeder

Byronkoeder

Member
Joined 2013
Bigun said:
Wow, sounds like too much BS to me - likely it was about damping factor. There are many different reasons for the sound of tube power amps but you can still get a nice sound from a tube pre and solid state power stage.
Click to expand...

Here is the video of Bob Carver. go to almost the end of the video is where he explains his theory on tube amps.../https://www.youtube.com/watch?v=LQ9USqpclWc
 
JMFahey

JMFahey

Member
Joined 2009
He explained that they get sound from the reflective sound wave bouncing off the speaker facing wall back to push the cone inward causing the coils to move creating a charge that is sent back to the tube via return line .
Click to expand...
Absolute B*LLSH1T, can't believe respected Bob Carver said such a thing?
Is the age showing?
So a SS and a tube amps , side by side driving speakers in the middle of a beach or a prairie (hint: no reflections) will sound exactly the same?
Pure unadultered cr4p.

this he said gives you that warm flavor sound we all love but An A/B solid state Chip amp cancels this effect not allowing the speaker cone to be effected by reflecting sound waves .
Click to expand...

Reflected sound has NOTHING to do with tube warmth, period.

There are many other artifacts behind this, many we like very much even if not very accurate, but *wall reflected* sound? forget it.

EDIT: and 1 minute later, even the Radio Host notices a problem with this, when he realizes things do not work as Bob Carver says, because there is an indeterminate but very long (relative to audio wave width) time delay on reflected waves which makes them lose all sync with signal input, in that case we can't talk of NFB.
Bob Carver just brushes it aside, says "oh yes, the acoustic time delay" and continues with his "explanation" as if it still held.
 
Last edited:
Byronkoeder

Byronkoeder

Member
Joined 2013
JMFahey said:
Absolute B*LLSH1T, can't believe respected Bob Carver said such a thing?
Is the age showing?
So a SS and a tube amps , side by side driving speakers in the middle of a beach or a prairie (hint: no reflections) will sound exactly the same?
Pure unadultered cr4p.



Reflected sound has NOTHING to do with tube warmth, period.

There are many other artifacts behind this, many we like very much even if not very accurate, but *wall reflected* sound? forget it.

EDIT: and 1 minute later, even the Radio Host notices a problem with this, when he realizes things do not work as Bob Carver says, because there is an indeterminate but very long (relative to audio wave width) time delay on reflected waves which makes them lose all sync with signal input, in that case we can't talk of NFB.
Bob Carver just brushes it aside, says "oh yes, the acoustic time delay" and continues with his "explanation" as if it still held.
Click to expand...

Well after all agree it BS what carver said Ill have to agree with you , But Im a newbie to Amp building and when hear something like this wanting to learn from one the pioneers of amp design you want to believe it. Im very Surprised Scot Wilkinson the host let that slide ....
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom