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Re: What's to chat about?
Posted: Sun Jul 11, 2021 4:12 pm
by Seth
Grant Bunter wrote: ↑Sat Jul 10, 2021 8:15 pm
^ Just remember that amplifiers put out AC volts and current.
You could probably do most of part 1 simply by multiple calculations, and confirm with a half reasonable multimeter.
And, also remember that resistors are used to reduce current flow, adjust signal levels, to divide voltages, and bias active elements.
As they heat up, and approach their limits, resistance may increase or decrease. Immediate variable.
Ducks guts, don't run your tests for a long time. Something will have to give, probably your amp.
How well do you understand passive crossovers? There's shunts to ground and heat I would suspect as immediate losses.
In order for you to quantify results, you need to know exactly what type of crossover you're using.
Someone much smarter than me once said "Energy can neither be created nor destroyed, it can only be transformed to another form of energy".
I only throw this in because, you might find that the expectations don't match the results. Doesn't mean that the expectations are wrong though, because there are intangible or insensate losses, losses you may not be able to or can't identify. But the energy in has to = the energy out. In which ever form it takes...
Duck's guts... never heard that before. Love the little sayings and idiom's from around the world... "Bob's your uncle" kinda things. Makes me wonder what sorts of things I may say that aren't universally understood the way I understand them.
Anyway, all good points Grant. The resistors I'm looking at using for a load are 100 watt rated, but I'll likely use 10 watts or less as the benchmark to make comparisons. Otherwise, I'd expect them to get very very hot, quickly. I'm certain the amp will be just fine. Maybe I should save my money and just use a Crock Pot as a load instead. LOL (kinda not joking. Kinda am. Kinda not)
I understand the basics of passive crossovers. Certainly not enough to design them without reference to a known design. Perhaps this test will be a learning experience beyond what I expect it to be. That would be great! Figured I'd just use what I have on hand and see what I see. I've got the one's that are ready to go into the WH6's, an SLA Pro that I can open up, as well as a couple of cheapy manufactured tops with blown drivers I could pillage from. Should be interesting. Like you said, some have an attenuation value designed into them. It will be interesting to measure and see the effects of that.
Someone much smarter than me once said "Energy can neither be created nor destroyed, it can only be transformed to another form of energy"
Her name was
Émilie du Châtelet, it ultimately became known as
The law of conservation of energy... equally as interesting as the Conservation of Mass. I'm sure most of us remember it from a science class or two.
Re: What's to chat about?
Posted: Sun Jul 11, 2021 4:38 pm
by Grant Bunter
Oh, and one thing I forgot to add.
Crossovers/filters reduce power by a set amount in dB per octave
So, if the reduction is 12dB/octave from 100Hz then there will no or minimal reduction at 100Hz, but should measure -12dB at 200Hz as an example...
Re: What's to chat about?
Posted: Sun Jul 11, 2021 4:58 pm
by Seth
Grant Bunter wrote: ↑Sun Jul 11, 2021 4:38 pm
Oh, and one thing I forgot to add.
Crossovers/filters reduce power by a set amount in dB
per octave
So, if the reduction is 12dB/octave from 100Hz then there will no or minimal reduction at 100Hz, but should measure -12dB at 200Hz as an example...
That's another good point to bring up
I don't know if it's the case for all curves or not, but Linkwitz-Riley is already down -6db at the designed crossover point. Butterworth -3dB. Will be interesting to actually measure that too.
If I used 8.94 volts as the benchmark voltage, I'd expect to see 6.32v at -3dB, 4.72v at -6dB, 2.24 at -12dB, 0.56v at -24dB. Wonder how faithful those measurements will actually be.
Re: What's to chat about?
Posted: Mon Jul 12, 2021 2:54 am
by Grant Bunter
Seth wrote: ↑Sun Jul 11, 2021 4:58 pm
That's another good point to bring up
I don't know if it's the case for all curves or not, but Linkwitz-Riley is already down -6db at the designed crossover point. Butterworth -3dB. Will be interesting to actually measure that too.
Mmmm yes that's true. What is "odd" about that though is the sum value if a low pass and high pass from 2 different filters is graphed, equals +3dB for Butterworth, and flat for LR..
Re: What's to chat about?
Posted: Mon Jul 12, 2021 11:02 am
by Seth
Grant Bunter wrote: ↑Mon Jul 12, 2021 2:54 am
Seth wrote: ↑Sun Jul 11, 2021 4:58 pm
That's another good point to bring up
I don't know if it's the case for all curves or not, but Linkwitz-Riley is already down -6db at the designed crossover point. Butterworth -3dB. Will be interesting to actually measure that too.
Mmmm yes that's true. What is "odd" about that though is the sum value if a low pass and high pass from 2 different filters is graphed, equals +3dB for Butterworth, and flat for LR..
Right? The LR makes sense right off the bat. But, I wonder what the Butterworth guy was thinking? Hmmm. Head scratcher.
So, I was thinking a little more about a test set-up and thought a little about testing without a dummy load. But, then remembered that some of the crossover parameters vary with load. Still doesn't mean I cant test without a load, but the results may be skewed from the actual intended values. Then I thought about just testing with speakers attached. I think that would be fine. Even though the impedance values wouldn't be static, I could still base the calculations as though they were... the impedance shouldn't change the measured voltage. Thoughts?
Re: What's to chat about?
Posted: Mon Jul 12, 2021 10:35 pm
by Seth
Re: What's to chat about?
Posted: Fri Jul 16, 2021 9:31 am
by Bruce Weldy
Alright.....after all the mind-numbing repartee about crossovers and impedance and other crap I don't understand. Here's what I'm doing while ya'll are talking theory.......
We started our annual Concerts in the Park. Because of the possibility of rain on the 4th of July, we decided to put all of the subs on the ground instead of stacking them with the OT12s on top. We put the three subs next to each other on both sides with the OT12s on stands behind them. It definitely added a fullness to the bottom end. So, we decided to stick with that last night.
Here's a link to the soundcheck with The Revs. Two of the girls and the guitar player are also in my band. I love mixing these guys/gals. Everything from Zep to The Bangles....
https://www.facebook.com/bruce.weldy.3/ ... &ref=notif
Re: What's to chat about?
Posted: Sat Jul 17, 2021 6:01 pm
by Rich4349
Re: What's to chat about?
Posted: Sun Jul 18, 2021 4:19 am
by Grant Bunter
Bruce Weldy wrote: ↑Fri Jul 16, 2021 9:31 am
Alright.....after all the mind-numbing repartee about crossovers and impedance and other crap I don't understand. Here's what I'm doing while ya'll are talking theory.......
Pfffft you're not fooling me.
"what would I know, I'm just a truck driver".
"what would I know, I'm just a farmer".
"what would I know, I left school at 13".
That's 3 from the three smartest people I know.
Hope you're having a ball with the concerts in the park Bruce...
Re: What's to chat about?
Posted: Sun Jul 18, 2021 4:03 pm
by Bruce Weldy
Grant Bunter wrote: ↑Sun Jul 18, 2021 4:19 am
Bruce Weldy wrote: ↑Fri Jul 16, 2021 9:31 am
Alright.....after all the mind-numbing repartee about crossovers and impedance and other crap I don't understand. Here's what I'm doing while ya'll are talking theory.......
Pfffft you're not fooling me.
"what would I know, I'm just a truck driver".
"what would I know, I'm just a farmer".
"what would I know, I left school at 13".
That's 3 from the three smartest people I know.
Hope you're having a ball with the concerts in the park Bruce...
I am.....
Re: What's to chat about?
Posted: Mon Jul 19, 2021 4:34 pm
by Seth
Had to put my headphones on to get a good feel for it. Bottom end is definitely there. The singers are nice 'n tight with the harmonies. Good mix too
Being a non-singer myself, I've always struggled with knowing what a singer needs in their monitor to effectively harmonize at an appropriate level to one and other. And fortunately/unfortunately the talent I've worked with doesn't have enough stage experience to know either. LOL
Re: What's to chat about?
Posted: Mon Jul 19, 2021 4:37 pm
by Seth
Hahaha. You give me too much credit Rich.
Re: What's to chat about?
Posted: Mon Jul 19, 2021 4:38 pm
by Seth
Grant Bunter wrote: ↑Sun Jul 18, 2021 4:19 am
Bruce Weldy wrote: ↑Fri Jul 16, 2021 9:31 am
Alright.....after all the mind-numbing repartee about crossovers and impedance and other crap I don't understand. Here's what I'm doing while ya'll are talking theory.......
Pfffft you're not fooling me.
"what would I know, I'm just a truck driver".
"what would I know, I'm just a farmer".
"what would I know, I left school at 13".
That's 3 from the three smartest people I know.
Hope you're having a ball with the concerts in the park Bruce...
+1
Well put Grant.
Re: What's to chat about?
Posted: Mon Jul 19, 2021 6:25 pm
by Bruce Weldy
Seth wrote: ↑Mon Jul 19, 2021 4:34 pm
Had to put my headphones on to get a good feel for it. Bottom end is definitely there. The singers are nice 'n tight with the harmonies. Good mix too
Being a non-singer myself, I've always struggled with knowing what a singer needs in their monitor to effectively harmonize at an appropriate level to one and other. And fortunately/unfortunately the talent I've worked with doesn't have enough stage experience to know either. LOL
That was just a sound check, it got better after they started the show.
Singers are all different, but I know I like to hear the vocals exactly how they are sounding out front. I actually would rather have them post fader so I can put myself in the right place with harmonies, knowing that will translate out front (especially if you have a "set it and forget it" soundman). This is especially true when you have multiple lead vocalists. Now, would I suggest that for other bands? No. Most everyone wants to hear ME and more ME.
They are my favorite band to mix. You have four lead vocalists and I get to add delay to give is some pizazz out front. I always run two Delays - each is only a single slap back. I set one to eighth notes and one to quarter notes. I have both of those Delay faders on my main mixing DCA (lead instruments and all vocals). I tap in the tempo on each song and ride the Delays at certain points for effect. Typically, it's just the shorter delay through out the song, but sometimes I'll bring in the longer delay at the end of a line to drag things out a bit. Especially on Whole Lotta' Love - and they do it pretty well - one of the girls sings it.
I stay engaged on every song - I'm paid to mix, so I mix. Too many sound guys fall into the trap of mixing the first couple of songs and then hit the bar......especially house guys in some of the venues. Don't be that guy.
I just advanced this week's show and the guy I was talking to was really excited that Mike and I would be providing sound. I've mixed 'em before. They are another amazing band with the highest level players around.....mostly R&B, Funk, Soul. Once you get a reputation for knowing what you are doing, it's way easier to get the bands to do the things you suggest.
While at my age, the loading and unloading is getting harder by the day, mixing is still a joy when it's the right band and players.
Guess I kinda' rambled on there......just started typing and kept going. Getting some time in my new X-Chair....trying to decide if I like it enough to keep it. I'm really picky.....it is replacing the old Steelcase chair I've been parking my fat butt in for over 40 years.
So, there's a topic - office chairs.....what do you like?
Re: What's to chat about?
Posted: Tue Aug 03, 2021 7:49 pm
by Seth
.
.
I've been out of town on a little vacation with limited internet for the past couple weeks. Had a great time, but it's good to be home again.
Bruce Weldy wrote: ↑Mon Jul 19, 2021 6:25 pm
Seth wrote: ↑Mon Jul 19, 2021 4:34 pm
Had to put my headphones on to get a good feel for it. Bottom end is definitely there. The singers are nice 'n tight with the harmonies. Good mix too
Being a non-singer myself, I've always struggled with knowing what a singer needs in their monitor to effectively harmonize at an appropriate level to one and other. And fortunately/unfortunately the talent I've worked with doesn't have enough stage experience to know either. LOL
That was just a sound check, it got better after they started the show.
Singers are all different, but I know I like to hear the vocals exactly how they are sounding out front. I actually would rather have them post fader so I can put myself in the right place with harmonies, knowing that will translate out front (especially if you have a "set it and forget it" soundman). This is especially true when you have multiple lead vocalists. Now, would I suggest that for other bands? No. Most everyone wants to hear ME and more ME.
They are my favorite band to mix. You have four lead vocalists and I get to add delay to give is some pizazz out front. I always run two Delays - each is only a single slap back. I set one to eighth notes and one to quarter notes. I have both of those Delay faders on my main mixing DCA (lead instruments and all vocals). I tap in the tempo on each song and ride the Delays at certain points for effect. Typically, it's just the shorter delay through out the song, but sometimes I'll bring in the longer delay at the end of a line to drag things out a bit. Especially on Whole Lotta' Love - and they do it pretty well - one of the girls sings it.
I stay engaged on every song - I'm paid to mix, so I mix. Too many sound guys fall into the trap of mixing the first couple of songs and then hit the bar......especially house guys in some of the venues. Don't be that guy.
I just advanced this week's show and the guy I was talking to was really excited that Mike and I would be providing sound. I've mixed 'em before. They are another amazing band with the highest level players around.....mostly R&B, Funk, Soul. Once you get a reputation for knowing what you are doing, it's way easier to get the bands to do the things you suggest.
While at my age, the loading and unloading is getting harder by the day, mixing is still a joy when it's the right band and players.
Guess I kinda' rambled on there......just started typing and kept going. Getting some time in my new X-Chair....trying to decide if I like it enough to keep it. I'm really picky.....it is replacing the old Steelcase chair I've been parking my fat butt in for over 40 years.
So, there's a topic - office chairs.....what do you like?
Bruce, I really enjoy your stories. Ramble all you like, any time.
What you said about the way you like your monitor mix makes the most sense to me. Otherwise, how does a singer really know where they are in the harmony in comparison to everyone else? Whether they need to back off the mic or get up on it some more? I suppose that opens another conversation about mic technique and how many singers have little idea what it is, let alone how to use it effectively. I get the "more me" thing with instruments, but more me on vocals when harmonies are a cornerstone of the performance... not so much.
I like your work ethic. Given the opportunity, I think I'd be the same way. At least, I am with what I do now anyway.
Office chairs... I like them with arms and a good comfortable recline/tilt... and free.
