Search found 39 matches
- Tue Oct 23, 2012 10:06 pm
- Forum: Sim City
- Topic: 46 Spice Models
- Replies: 1
- Views: 5750
- Wed Oct 10, 2012 10:57 am
- Forum: Sim City
- Topic: Drop Down Menus for selecting your tube
- Replies: 28
- Views: 62563
- Sun Oct 07, 2012 7:19 pm
- Forum: Sim City
- Topic: Drop Down Menus for selecting your tube
- Replies: 28
- Views: 62563
- Fri Oct 05, 2012 1:02 pm
- Forum: Sim City
- Topic: Drop Down Menus for selecting your tube
- Replies: 28
- Views: 62563
- Mon Nov 29, 2010 7:01 pm
- Forum: Circuits
- Topic: new jc circuits
- Replies: 51
- Views: 53693
ETF was great, loved your presentation, JC! That pre didn;t sound too bad, either.
Some photos from the event, here:
http://s108.photobucket.com/albums/n15/ ... o/ETF2010/
Cheers,
Pete
Some photos from the event, here:
http://s108.photobucket.com/albums/n15/ ... o/ETF2010/
Cheers,
Pete
- Tue Jul 06, 2010 9:21 pm
- Forum: Phono
- Topic: Audio Note M10
- Replies: 15
- Views: 34837
- Tue Jul 06, 2010 12:10 pm
- Forum: Phono
- Topic: Audio Note M10
- Replies: 15
- Views: 34837
- Sun Nov 29, 2009 2:21 pm
- Forum: Transformers
- Topic: Inverting Interstage Transformers.
- Replies: 5
- Views: 8245
Ooh! Nice one Dave. A couple of years ago I built the Shishido 801A amp (as published in SP10) but with different filament supplies. I managed to luck into a complete set of iron on eBay. The Tango interstages (10672, I think?) were custom made with something like a 1:0.8 step-down. The data sheet r...
- Fri Jul 24, 2009 1:00 pm
- Forum: Attenuators
- Topic: boxed up autoformer
- Replies: 6
- Views: 6655
- Tue Jan 13, 2009 7:32 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
- Tue Dec 23, 2008 10:30 am
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Some info on 'k' here:
http://www.burnyourbonus.info/sci.elect ... d1748.html
There's a mention that k=(1-Llp)/Lp
I'm still digesting the rest of it!
http://www.burnyourbonus.info/sci.elect ... d1748.html
There's a mention that k=(1-Llp)/Lp
I'm still digesting the rest of it!
- Mon Dec 22, 2008 11:56 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
- Mon Dec 22, 2008 11:23 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
I think the 'k' factor is simply a shorthand way of expressing the leakage inductance (and perhaps other parameters) but in this case we're modelling them directly so we don't need to account for it elsewhere. I think it would be useful to added semi-realistic capacitances so that we're accurate as ...
- Mon Dec 22, 2008 8:25 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Thanks Dave, that looks like an easier load. I wonder if it's possible to tweak the values to help that in the first case, but perhaps it is what it is... I was kind of holding off modelling capacitances until we had the basis circuit, but given the sensitivity to source impedances, it doesn't reall...
- Mon Dec 22, 2008 9:13 am
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Hiya Dave, hey guys. Lars, I ran your version and the pic is below. When I put a 4700uf bypass across Pete's Rx3 I saw a similar response. Pete, what is the rational between the progression between RX1 and RX3? what purpose do the extra parts in Rx3 serve? RX1 was just a first step using the inverse...
- Mon Dec 22, 2008 12:16 am
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
- Sun Dec 21, 2008 8:33 am
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Hi Guys, Well, the only LRiaa design I know of (from Steve B) uses two IT's in series. This design is simpler than that which I like. Why the leakage inductance should be in the transformer is a good question. The way I see it is that this 'virtual' component might well be a 'perfect' one as long a...
- Sat Dec 20, 2008 8:47 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Hi guys, I'm not and expert on modelling, so I don't know if that's the correct model for this. The text talks about the time constants coming from the leakage inductance which itself relies on lossy coupling. I'm not sure how the leakage inductance and 'k' factor should be considered in SPICE. My q...
- Sat Dec 20, 2008 12:28 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Thanks guys! NC, can we not simply model it as a perfect transformers + leakage inductances? I did a couple - RX01 is just a model using voltage sources to model the transformers and RX03 is an attempt at a practical circuit using 437A. I;m not sure whether these are complete and we need to account ...
- Fri Dec 19, 2008 7:13 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Ah, I figured you would already be onto it Dave! :D These were the pages which set me off, which seem to indicate a production piece: http://www.audionote.co.uk/news/article_pre_06-06_m9.shtml http://www.audionote.co.uk/products/preamp/m9_phono_01.shtml I'm sure win true Audio Note style it's mind-b...
- Thu Dec 18, 2008 8:47 pm
- Forum: Phono
- Topic: Transformer phono correction
- Replies: 54
- Views: 52549
Transformer phono correction
I've been at phono stuff recently and was reading that Audio Note are using Transformer RIAA correction. CV pointed me in the direction of this (I assume the Audio Note solution is similar to this): http://www.aml.nm.ru/RX_corrector_eng.htm Looks like an interesting way of doing things. Does anyone ...
- Wed Dec 17, 2008 9:34 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
- Fri Dec 12, 2008 10:00 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
- Wed Dec 10, 2008 10:43 am
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
- Tue Dec 09, 2008 11:02 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
I loaded the 10k network with 12k and the tube with 5k. This means that the tube will actually see about 3.5k. SPICE seemed to think this was ok. I did find the 10k network to be more sensitive to source and load impedances than the 600 for some reason (possibly I'm doing something wrong, can't thin...
- Tue Dec 09, 2008 7:38 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
Well, I tried the 448As as Tetrodes into some Silk 10k modules I had lying about. I loaded the tubes with 5k and the network with 12k at the other end. This gives a good response in SPICE. Overall gain is good at over 40dB. Subjectively, it sounds very, very good. I've also simmed it using a cascode...
- Sun Nov 16, 2008 5:57 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
I did sim this in SPICE, using a D3A pentode as first stage and a triode second stage - it comes at out about 56dB gain! So gain is not really an issue. I wonder if it even needs a second stage... Is that for the 7k3? Sounds roughly right. I get 50db or so with the 1k5 and the right valves, second ...
- Sun Nov 16, 2008 2:56 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
Agreed, however, a step down and a high gm triode would drive a 7k-ish LCR, I would have thought. Ageing would still be an issue, wouldn't it? Yeah, using a triode to set source Z is a non starter in my book for that very reason, but a the down and a fixed load should ameliorate most of that, which...
- Sun Nov 16, 2008 12:24 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389
Thanks Andrew, presumably a high-Gm triode would still be quieter though, because it lacks the other noise sources of the pentode? This seems a very elegant way to use the LCRs. I was just wondering as Morgan Jones goes into noise in his book and discards pentodes as being too noisy. I've never trie...
- Sat Nov 15, 2008 11:44 pm
- Forum: Phono
- Topic: 7K30 LCR to load a pentode.
- Replies: 20
- Views: 18389