How critical is the 47K5 resistor at the input ?
I'd have thought that a standard 47K could be used here.
I've ordered all the correct components but for some reason the 47K5 are out of stock.
I'd have thought that a standard 47K could be used here.
I've ordered all the correct components but for some reason the 47K5 are out of stock.
Anywhere from 22k to 220k would do.
47k is perfect.
I do not understand why some builders/designers use E96 values for components where tolerance is not a serious issue.
Matching of resistors is often a benefit.
But that does not mean 47.5ohms +-0.1%. It means match to +-an appropriate tolerance, but the components could be anywhere in the +-1% range and in many cases +-5% would not make a significant difference.
eg the emitter resistors in a BJT LTP could be specified as 100r
99r and 101r will make a small difference in performance.
But using 99r and 99r2 will be virtually the same as using 100.8r and 101r
The matching is what is more important. The absolute value is relatively unimportant. The LTP would probably work very well with 98r & 98.2r and probably OK with 105r and 105.2r
47k is perfect.
I do not understand why some builders/designers use E96 values for components where tolerance is not a serious issue.
Matching of resistors is often a benefit.
But that does not mean 47.5ohms +-0.1%. It means match to +-an appropriate tolerance, but the components could be anywhere in the +-1% range and in many cases +-5% would not make a significant difference.
eg the emitter resistors in a BJT LTP could be specified as 100r
99r and 101r will make a small difference in performance.
But using 99r and 99r2 will be virtually the same as using 100.8r and 101r
The matching is what is more important. The absolute value is relatively unimportant. The LTP would probably work very well with 98r & 98.2r and probably OK with 105r and 105.2r
I have occasionally referred to you as Katie's Dad.
You have not confirmed if you are Katie or Dad.
You have not confirmed if you are Katie or Dad.
It depends on what time of day. It's Katie at the moment. Dad comes home depending on what shift he is on and uses my account.
Could be that it's a result of Mouser having RN60 47k5 in stock instead of RN60 47k.
The only stupid questions are the ones you don't ask...
🙂
Do you need the PCB? No.
Will the PCB help make it easier and hopefully eliminate many wiring errors? Yes.
I strongly suggest using the PCB for the amp and PSU. It makes things simpler and the entire process will be easier and more streamlined by using them. 😀 😀
Dad is better than I am, I only learnt electronics as part of my HND. As my boyfriend is into it all I tend to help him along sometimes. I'm more of a systems analyser than raw electronics.
Andrew - I'm really confused now. I feel like someone just pulled back the curtain on a Wizard Of Oz event. 
😀
😀
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And what problem is it you have with us girls liking electronics too. Now you can see why I hide behind my dads identity.
I assumed "KatieandDad" was a sign of father and daughter bonding over a common interest, and wished I had something like that with my daughter. She keeps asking me to build her things but shows no interest in picking up a soldering iron.
I doubt anyone has any problem at all with your interest in electronics, Katie. It is something that usually doesn't interest girls, and we are just a little surprised that's all. Happy to have you here and hope we can all have fun and learn something together.
I doubt anyone has any problem at all with your interest in electronics, Katie. It is something that usually doesn't interest girls, and we are just a little surprised that's all. Happy to have you here and hope we can all have fun and learn something together.
"And what problem is it you have with us girls liking electronics too. Now you can see why I hide behind my dads identity."
I hope that's not pointed at me. My daughter raided the Accenture Corporate Management culture, braids and all, and is sitting just under the Partner level - as we speak.
All I can do is repeat an Opra thing -"You Go Girl !!!" 😎
Andrew's detective work was the base of my comment.
I hope that's not pointed at me. My daughter raided the Accenture Corporate Management culture, braids and all, and is sitting just under the Partner level - as we speak.
All I can do is repeat an Opra thing -"You Go Girl !!!" 😎
Andrew's detective work was the base of my comment.
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It doesn't help that three of us use the same account. I get the blame for some of the comments that the boys come up with.
Phillip (my boyfriend) is on here too, it is him building the speakers. I'm working with dad on the active crossovers.
Phillip (my boyfriend) is on here too, it is him building the speakers. I'm working with dad on the active crossovers.
😀 there will never come any good out of sharing a personal account🙂
People think they are dealing with one person with split personality😀
it may help if all of you sign every message.
People think they are dealing with one person with split personality😀
it may help if all of you sign every message.
Over time I have run into examples of DIY F5's that were marginally stable
or perhaps a bit twitchy on the top end.
My own observations of the top end of the F5 with some of the full range
drivers was that it was a bit like "putting instant coffee in a microwave oven"
I went back to that recently and found that increasing the value of the 1K
input resistor to as high as 4.7K helps this, and recommend that people
experiencing overly bright sound or instability try it.
The resistance forms a low pass filter the input capacitance of the Jfets, and
takes the bandwidth down from the 1 megahertz region.
😎
or perhaps a bit twitchy on the top end.
My own observations of the top end of the F5 with some of the full range
drivers was that it was a bit like "putting instant coffee in a microwave oven"
I went back to that recently and found that increasing the value of the 1K
input resistor to as high as 4.7K helps this, and recommend that people
experiencing overly bright sound or instability try it.
The resistance forms a low pass filter the input capacitance of the Jfets, and
takes the bandwidth down from the 1 megahertz region.
😎