Bl**dy hell why didn't I think of that...nice oneDave the bass wrote: High-ish power 8R's mounted onto a likkle box with handy meter an 'scoping points.
DTB
Search found 1453 matches
- Tue Oct 13, 2009 6:35 pm
- Forum: Everyones Projects
- Topic: An amp called 'Do(e)': A Deer, a female deer.
- Replies: 361
- Views: 85411
- Tue Oct 13, 2009 7:01 am
- Forum: Beginners
- Topic: Cassette Tape and Computer
- Replies: 79
- Views: 31033
- Tue Oct 13, 2009 6:44 am
- Forum: Everyones Projects
- Topic: An amp called 'Do(e)': A Deer, a female deer.
- Replies: 361
- Views: 85411
Dave, I've just thought of something. Maybe you could build a prototype of the output stage of the amp: Cap couple to the output stage. Provide say 150v regulated supply. Use variable negative grid bias. That way you could vary the grid bias, thus varying current through the output stage, and hear t...
- Tue Oct 13, 2009 6:33 am
- Forum: Everyones Projects
- Topic: An amp called 'Do(e)': A Deer, a female deer.
- Replies: 361
- Views: 85411
Is that because (referring to the last page of the link) transconductance is very low at low ra? So increasing the Anode load resistance increases gm to a more useful level? Not quite, we need to think of things the other way round. Where we decide to operate the valve (our choice of plate volts an...
- Mon Oct 12, 2009 8:53 pm
- Forum: Suppliers, recommended or not
- Topic: JIAJIA AUDIO
- Replies: 31
- Views: 15801
- Mon Oct 12, 2009 8:52 pm
- Forum: Suppliers, recommended or not
- Topic: JIAJIA AUDIO
- Replies: 31
- Views: 15801
- Sat Oct 10, 2009 11:43 pm
- Forum: Everyones Projects
- Topic: 211 push-pull
- Replies: 310
- Views: 104667
- Sat Oct 10, 2009 7:14 pm
- Forum: Everyones Projects
- Topic: 211 push-pull
- Replies: 310
- Views: 104667
- Sat Oct 10, 2009 5:57 pm
- Forum: Everyones Projects
- Topic: 211 push-pull
- Replies: 310
- Views: 104667
- Sat Oct 10, 2009 8:27 am
- Forum: Speakers
- Topic: Open baffle vs in-wall
- Replies: 16
- Views: 9817
What would worry me is the wall having a resonant frequency at which it will vibrate. Even brick ones ... :shock: . I know what you mean Mike, but as I said in the reply to Will, I'm not looking for the really low frequencies where this would be a problem. I'm thinking of an installation where a se...
- Sat Oct 10, 2009 8:16 am
- Forum: Speakers
- Topic: Open baffle vs in-wall
- Replies: 16
- Views: 9817
Max this is all about sub bass but that the area going to give problems. Look at the gallery on the forum. http://home.comcast.net/~infinitelybaffled/ . Thanks Will, I'll check it out. But for now I'll just say that for me personally the very low frequencies aren't that important for my musical enj...
- Sat Oct 10, 2009 8:07 am
- Forum: Speakers
- Topic: Open baffle vs in-wall
- Replies: 16
- Views: 9817
Hi Max For some reason I was getting preoccupied with the baffle affect, moreso than thinking about whats behind the driver...... had you thought about mangers, you don't have to worry about whats behind with those I'll shut up now cos I'm neurotic about point source so I'm not really the right per...
- Sat Oct 10, 2009 7:25 am
- Forum: Everyones Projects
- Topic: An amp called 'Do(e)': A Deer, a female deer.
- Replies: 361
- Views: 85411
Dave, if you look at the last page of the sheet that Mike has linked to, we can see what happens to rp and gm as we move the op point. They have plotted for fixed values of plate voltage and varied the grid voltage, but we could also think of it as varying the grid current. Do we want high rp or low...
- Fri Oct 09, 2009 6:41 pm
- Forum: Speakers
- Topic: Open baffle vs in-wall
- Replies: 16
- Views: 9817
Thanks for the link Ed. Interesting as far as it goes, but the writer seems to be aiming at generic in-wall speakers where you just cut a hole in the plasterboard and stick them in. I have some Speakercraft speakers in my kitchen ceiling. They aren't particularly high end, but they did come with sea...
- Fri Oct 09, 2009 12:55 pm
- Forum: Everyones Projects
- Topic: Owstonski.
- Replies: 307
- Views: 67032
Phil, just to put these numbers into context, MJ discusses this on p494. He talks about traditional valve amps having 1M input resistance, and some modern designs dropping this to 100K to reduce noise induced by the heater wiring of the first stage. So if you are needing to go down to 2K something i...