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Quick analysis and comment. The supply you posted is neither fast or optimal. High HYs and high Cs are NOT your friends. Use as little as possible to get the job done.
In Push Pull, you can have 2 VAC of ripple to the Finals and it will not be a problem.
I have simulated your supply, guessing at the DCR of the 300 mA. rated power transformer. It is pretty poor at a 15% current step test. It settles in about 550 mS., and has a dynamic Z of (12 volts drop divided by 31.2 mA. current change, or,) 384 Ohms.
My suggestion has under 1 VAC of ripple, inaudible to the Finals in P-P, and it settles in 30 mS (18 times faster) and drops only 3.8 VDC on a similar 15% current step. The Dynamic Z is (3.8 VDC drop divided by 15.75 mA. current change, or,) about 241 Ohms.
Your supply uses two expensive 5AR4 cathode type rectifiers, my suggestion is to use two less expensive readily available 5U4GBs. Such a tube rectifier has NO cathode, and it sounds good. Buy a good Hammond 300 series (highest possible current rating) transformer, a shared L1, which can do 2 A. of current, and a "Y" arrangement of two inexpensive EDCOR 2 HY 21 Ohms open frame chokes, one for each channel.
I have drastically reduced the DCR, HYs, and uFs in the supply.
What I suggested, what I would term a "modern " power supply will ROCK on playing music and it will be worthy. The amp will now kick butt.
I have only quickly considered the supply to the finals, I would use a R/C to the front end, and those values can be easily be determined in PSUD, shoot for 1 or 2 mVAC of ripple.
This is just my initial idea, I know it will play well, and I avoid L-Critical supplies, unlike many others here.
The amp schematic I posted was one built by Kegger on AK. Its one of his personal amps he uses. He sent me the schematic of his finished amp which he likes the sound of very well, so this is not something I designed.
I don't know that I'll make any changes in the amp section, but the power supply looked .....let's say, not right. Maybe a bit too big and slow (compared to the vintage stuff I'd been rebuilding). I know there is a wealth of collective experiential knowledge here and since I don't know what I'm doing, but know what I want to hear, I thought 'why not post?'. Heck, I don't really prefer tube rectification. Some Schottky diodes might do the job better.
I'm not a builder or designer. When it comes to that I'm a total newbie, so that's why I came to this forum. I don't mind trying ideas out and taking time to get it right. My ears will tell me if things are right or not.
I bought a set of 1978 Klipschorns and everyone was telling me how great they were. I did not like them. Too harsh, even after replacing the crossover caps. Sold 'em. Got a set of Von Schweikerts now. Seller told me how great they were. I didn't like them at first, but after rebuilding the crossover I love them. So I'm not an opinion follower, except for my own and that is derived from my own ears.
This 6AV5 amp should put out around 12-15 WPC according to Kegger which is a bit more than the 8.5 WPC single-ended amp I'm using with the VS speakers now. I want a little more power than 8.5 watts for these speakers. You'd recommended to use the Hammond 372 series PT. Does it put out enough B+ voltage as is needed for this amp? I'd like to overbuild a bit and not have things run too hot.
The hole in your argument is that at 20Hz
the current will increase for only 12.5ms.
Then the current will decrease because
it will be on the downside of the sinewave.
So he will see a drop of only 2.6V during use.
I am not saying anything about the sonics here.
Did you notice the DCR specifications on the Hammond PT I posted ?? Could you MEASURE the BFT-1b on both sides, and please post the DCRs so we will know what that is. The BFT-1B data sheet totally ignores the specification, Hammond certainly does not, and I am guessing the designer was unaware of low DCR.
You have the power trannie, right there on your premises to easily measure. Thank you !!
As to "holes" in analysis (at 20 HZ.!!), that is fine with me, the analysis is only there to get DIY types interested enough to LISTEN to such a supply. Then it usually becomes " I'm ALL IN " as per deathtube667, rage, Drummerwill, lakerfan, etc, etc. :-)
DCRs si'l vous plait monsieur.
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