John Curl's Blowtorch preamplifier part II

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the main difference across the pond is that in USA intervention is almost encouraged as doctors can charge for it.

Not always the case, my doctor suggested I tough out a herniated L7 (you could have sawed my leg off every morning for a month and I wouldn't have noticed) because once you intervene the chance is you do it again and again. It's been fine for 32 years.
 
JN

Take a closer look the first two rings are about where expected from cable length bounce. The load is a compression driver. Now who would expect the voice coil to have a resonant frequency? (Clue = anyone!). As to the drop after the zobel we could look at the source impedance 50 ohms from the generator feeding a 5 ohm resistor gives about 4.5 ohms. Add the zobel load and the driving signal also drops so no surprise the ringing drops.

Pretty much no unexplainable results. Just not what was initially expected as not all real variables were considered. Who knew doing real experiments may expand one's view?

Thanks for your comments.

BTY wonder if it would be perceptable if the cable length resonance and the driver resonance matched?
 
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Scott: I did say 'almost'. Glad it fixed itself.

Rsavas: over simplistic (see Mediterranean diet research to show that a glass of red a day may do considerably more good than harm) but I would agree tobacco should be encouraged out of use. Shame as nicotine is an amazing drug and on its own not significantly harmful, its just all the other stuff in a smoke. But this line rapidly descents into a stock high school debate on the ethics of restricting and individual's rights !
 
When my dad lived in Florida he and his wife flew to Costa Rica for dental work. They had a nice tropical vacation and the money they saved was more than the price of the trip.

A client of mine from Quebec had a stroke and as part of the follow up had to get blood work pretty regularly. He and his wife wintered in Florida ( not that unusual for elderly snowbirds) and he went to a local clinic to draw blood and send it off for tests. They charged him a couple hundred bucks. Then his wife said "You idiot, you have your Quebec provincial health insurance, the clinic will take that and charge the system, why are you paying out of pocket?". So he did, and they accepted it. When he got home he had a letter from the provincial health insurance folks telling him they would only pay a maximum of $800 for blood tests and he would have to make up the remainder of the $2500 they billed. So the clinic charged MORE when they knew they were billing an insurance system vs a cash walk-in. (I realize it costs money to fill out the forms and wait to get paid, but....)
 
I also have Pono and HD800. Plus some others.
Nice to offer selection of filters and PLL topologies..... good feature set.
I hear little difference in actual sound quality between the different PLL settings, but the "Exact" setting is intolerant of incoming latency, so unusable with streaming audio. The filter setting differences are subtle and with most files inaudible, however with recent HD files like the Bill Frisell "Guitar In The Space Age!" HD, the nature of the ambience is different when using different filters...which one is correct? Without being at the mastering session I couldn't tell you. The Auralic Vega is a fine sounding DAC, however you configure it.
What got you to buy the Benchmark amps?
THx- Richard
We didn't end up buying one, but we needed a good amp in our Production Room so I trialled the Benchmark owned by another local station and it is pretty ballsy and uber clean, as good as any amp I have been critical of. Since the room and speakers are non-optimum that's about all I will attest to. I might buy one if i was in the market, but I'm still using old US B&K amps and find them to be quite good and a redeeming virtue is...they are paid for.

Cheers!
Howie
 
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Dick, you have your own eccentric views on these matters and you are certainly welcome to them. They are not "the only way" that works for everyone. In fact for a larger family the educational expense issue is even bigger, if that is someone's choice there are very different answers.

Of course, situations vary as does the priorities of individuals and/or families. Does that really have to be pointed out to anyone?

My eccentric views -- I like that word ----

Glad Waly is done ranting....... but I am sure he hasn't gone far.



THx-RNMarsh
 
JN

Take a closer look the first two rings are about where expected from cable length bounce. The load is a compression driver. Now who would expect the voice coil to have a resonant frequency? (Clue = anyone!). As to the drop after the zobel we could look at the source impedance 50 ohms from the generator feeding a 5 ohm resistor gives about 4.5 ohms. Add the zobel load and the driving signal also drops so no surprise the ringing drops.

Pretty much no unexplainable results. Just not what was initially expected as not all real variables were considered. Who knew doing real experiments may expand one's view?

Thanks for your comments.

BTY wonder if it would be perceptable if the cable length resonance and the driver resonance matched?
Actually, it was pretty much what I would initially expect. Audio stuff at 1 uSec timing is always doing that kind of thing.

To really examine your setup, I'd actually need details of your setup. Working with very little actual information, well....I've come to expect that now.:D

Cheers,

John
 
My eccentric views -- I like that word ----
THx-RNMarsh

In some markets getting rid of your mortgage is a bad (or at least a financially disadvantaged thing) for instance. You are not a financial professional don't offer advice like you are one. Speaking of cheap my wife's sister has a health problem and she wants her around in FL so we bought a house for $40,000 cash no income tax in FL. and real estate tax is $280 a quarter and we don't have to go to Thailand.
 
Speaking of DAC's... This is DIY Audio after all. What is a DAC one can build that has pretensions to high performance but minimal snake oil appeal? If one can forego USB (not important in my use case) is there something decent where one can buy a PCB, stuff it, mount it in a case, and expect better than average performance?
 
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. You are not a financial professional don't offer advice like you are one.

Speaking of cheap my wife's sister has a health problem and she wants her around in FL so we bought a house for $40,000 cash no income tax in FL. and real estate tax is $280 a quarter and we don't have to go to Thailand.

I only say what I do and not what others ought to do. I also use financial prof and lawyers.

If you like Florida weather, hurricans and all, fine for you... sure is cheaper than calif... but you get what you pay for, IMO. Or are you giving financial advice?

I don't always do what is best financially, in any event; My aging neighbors of long time were going to have to sell and move -- with only retirement income and they did not get their home paid off before they retired (hint), it wasn't enough income.... No margin for doctor visits or house repair or car repair. In order to keep them near me and reduce their house payment, I talked to them and decided to give them $43,000 USD. Now my friends are still near me and they have better life also. I could have paid off some of my own debt or bought some nice audio/video stuff. It is all about one's priorities.



-RM
 
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