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captainbeefheart

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  1. Bingo! Contemporary music I find is more geared toward choreographed dancing and less about artistic musical expression.
  2. People ask me all the time what SET amps they should buy and I always push them towards the Elekit 300b amps. The circuit is very well designed and the performance and sound quality is far better than many 300b amps costing far more money. Mosfet B+ ripple filter DC filaments Switchable feedback from -8db to no feedback. I am very impressed with the Elekit 300b amp and that says a lot since I am extremely picky about designs.
  3. Zeppelin was great at mixing time signatures. Black dog has 4/4, 3/4, and 5/4 The Ocean 4/4, 7/8 The Crunge 9/8 Yes!! Fell on Black days 6/4 Limo Wreck 15/8 My Wave 4/4, 5/4 The day I tried to live 4/4, 7/8 Spoonman 7/8
  4. I have tons of records and enjoy them immensely, I'm not a perfectionist digital snob by any means. I read an article written by one of the big recording engineers, the name escapes me but he claims that some high frequency cross talk between channels improves the sound and is one of the reasons people love to listen to vinyl. So he actually mixes this high frequency cross talk into near perfect digital recordings to emulate vinyl on CD or streaming formats. I found that very interesting.
  5. It's not irrelevant when you are listening to stereo recordings the other 50% of the time. Of course that is only if you have a source capable of excellent channel separation for stereo recording playback. Vinyl stereo playback systems have awful channel separation. Not really, no. If you are on the fence about whether to get mono amps or a stereo unit ask yourself what source do you use most? If you say vinyl then the cross-talk is horrendous with vinyl playback and mono amplifiers aren't going to matter since the pollution has already taken place at the source. If you listen to digital sources then mono amps will be technically beneficial the other 50% of the time when you listening to stereo recordings. Digital sources have excellent channel separation compared to vinyl playback. There are other benefits to running mono power amps other than channel separation. It's the lesser of two evils to have longer interconnects, especially balanced ones while keeping the mono amplifier directly next to the speaker with a very short speaker cable length.
  6. If two separate channels process identical information then it stands to reason that cross talk through a shared power supply won't cause the same issues compared to two separate channels processing two different sets of information. The cross-talk pollutes one set of information from the other; each output no longer contains only the pure information that was at it's inputs. So if the two separate channels both contain identical information then cross talk won't matter and there is no benefit to two mono amps.
  7. Here are some plots for different operating points. Readings taken at 10vrms output into 100k load. I have never seen a tube with no external feedback measure .0022% THD Although that's extremely low distortion there are some higher harmonics. It's not enough to sound horrible since 2H is still dominant but the second plot that's recommended Va=235 and Ia=28mA is still very low distortion at .028% THD but it's all second harmonic. Of course this is for line stage applications, the test is measured at 10vrms output, at 2vrms which most of the time is all that is needed to drive a power amp this tube is squeaky clean. If you want to try some I can send a couple your way as a Christmas gift. https://www.mvaudiolabs.com/tubes/tube-data-library/4p1l/
  8. @henry4841 have you tried the 6AV5GA strapped as a triode yet? I know you like the 6Y6 a lot and it is a nice tube I found the 6AV5GA to sound better. Another tube that is better than the 6AV5GA and probably the best sounding tube I have ever heard in my life is the 4P1L. It's a Russian directly heated pentode but of course wire it as a triode. I thought something was wrong the first time I was taking distortion measurements it's that linear. It was a tough fight between the 45 and the 4P1L in my book for best no feedback sound and I have concluded the 4P1L is better sounding. I really think you would like both. I sent curiousgeorge some 4P1L's but not I don't think he has had the time to mess around with them yet. The 4P1L being directly heated filament is a little tougher to setup in that it works best with DC filaments like all directly heated triodes do. The 6AV5GA is much simpler to build with due to it being indirectly heated 6.3v heaters.
  9. Don't believe everything you read on the internet. In what way is the connector limiting performance?
  10. Pots don't always have to be noisy from something physically wrong like oxidation or contamination of the track. Since it's only one channel and it's a sealed pot you could be experiencing some DC current leaking by from a faulty capacitor. DC current passing through a pot makes noise when turning just like it was dirty. Of course it could just be a dirty/oxidized pot even though it's sealed. Careful disassembly and cleaning of the pot can resolve the issue. Anything assembled can be disassembled, pots included.
  11. Of course it's a fine little amplifier, I wouldn't be spending my time on it if I didn't like the design. It's got the hallmarks of things I'm into like the 6Y6 tube. That's not a tube you hear about all the time like the chocolate/vanilla EL34/KT88 amps that flood the market. Elekit makes a nice 300b amplifier that has a switch to add 8db of feedback or leave it open loop. I'm not saying this amp needs negative feedback, but it might be a nice option for the end user to be able to decide for any recording they listen to or any pair of speakers they might have. It's just a simple "mod" that gives the end user more options and versatility. I know it's not needed but options are fun I think.
  12. The magnet wire on the coil is extremely thin. It also has a thin layer of insulation covering the outside which makes it hard to get a resistance reading with a meter by just touching it. If you can read through the voice coil, which sounds like you can then re-connect the thin magnet wire to the terminal. The heat from soldering should melt the insulation off the magnet wire in the connection or you can clean it off before soldering.
  13. I'm glad Henry was helping with measurements because I was going to just blame the OPT for the treble roll off. Since Henry was getting the same roll off with the Hammond's I figured something else had to be going on which looking closer at the 6Y6 in triode mode's input capacitance and the source impedance of the driver stage the numbers fit perfectly. I even checked with a simulation since I dismantled the breadboard sweetie circuit. Miller capacitance is rearing it's ugly head. There is enough gain to which one could try and change the 100k plate load resistor for the 6SJ7 to a lower value, maybe try 82k which should help lower the output impedance of that gain stage. This should bump the corner frequency past 20kHz and only bump the open loop gain from 17db to 15.5db. Since the limitation is in the circuit itself and not the output transformer than I change my advise to not spend big money on a high bandwidth output transformers.
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