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description: Audio advice and discussions with audiophiles and professionals. Free discussion forums, open to all and frequented by industry experts. Ask questions and get advice on stereos, speakers, hi-end amplifiers, pre-amps, home theater, tube hi-fi, turntables, vinyl, tweaks, music, films, video, DVDs and more.
items: Crossover help: more confused than ever!
items: Re: Crossover help: more confused than ever!
items: abandon hope all ye who enter......!
items: some component calculators
items: Kama Sutra Series/Parallel
items: LIVE NUDE PARALLEL GIRLS! GIRLS! GIRLS!
items: Re: LIVE NUDE PARALLEL GIRLS! GIRLS! GIRLS!
items: Hey Garland! Cut me some slack!!!!

Crossover help: more confused than ever!
type: item
description: This series/parallel thing is making me crazy. The archived posts between Wayne and Jeff and Mike with Wayne having an "Happy Gilmore" moment, yikes! I got the new crossover schematic for the Theatre 4's, thanks Wayne, and understand the woofer zobel thing. But the tweeter network is beyond me. See "Happy Gilmore" above. Once again, I currently have a 16 ohm resistor between the + and - posts of the tweeter output of the crossover and another 16 ohm joined to a .47uF cap between the + tweeter crossover output and the + tweeter. At this point I don't even know whether I have an R2! Could somebody maybe post a drawing showing the positions and values for an idiot like me? Or at least a "thigh bone is connected to the knee bone" type thing. Thanks and Happy Holidays to all.
creator: BillEpstein
date: 2001-12-22T02:15:10-00:00

Re: Crossover help: more confused than ever!
type: item
description: OK. Let's roll our sleeves up. First of all, the 16 ohm resistor across the crossover's tweeter output is exactly right. That's your R2 resistor. But now that one takes the full power of the amplifier across it from 2kHz up, so let's refresh ourselves on the "Happy Gilmore" ohms law thing. But this time without the Bob Barker scene. Resistors in series are simply added to calculate total resistance. Two identical resistors in parallel equal 1/2 the resistance value of either. The actual formula is: Rt = 1/(1/R1 + 1/R2 ...) You don't have to connect networks of resistors together to form a single resistance, as I often suggest. I make this suggestion just so people can obtain the proper value resistors having the necessary power requirements. But a person can use a single resistor just as well, and it's much easier. Since music content is weighted towards the frequencies below 2kHz, you probably won't have full power across this resistor - but you could have. Still, you probably can consider that 1/10th power is sufficient for this part, for various reasons. If you're running a 100 watt amp, then a single 10 watt part is probably plenty in this location. If you're running a SET, you could put a little 1/2 watt part here. But just remember that this one takes the load. The 0.47uF capacitor C1 is connected in parallel with the 16 ohm resistor R1. These are placed in series with the compression driver. If you cannot remember how series and parallel connections are made, it might be worth your time to search for a book or another reference to show you. You can probably even find a "thigh bone is connected to the knee bone" type thing on the internet. The schematic shows C1 and R1 connected in parallel, and the actual, physical connections are just like they are shown on the schematic. An example of a series connection is shown as R3 and C5. These are two devices that have been connected in series with one another, and they are also connected physically exactly as they ar…
creator: Wayne Parham
date: 2001-12-22T05:06:30-00:00

abandon hope all ye who enter......!
type: item
description: O.K., 2- 32 ohm 10 watt resistors joined in parallel form 1- 16 ohm 20 watt, errrr thingy. 2 thingy's joined in parallel make 40 watts power handling but only 8 ohms. So there must be a formula for joining 4 resistors into 2 parallel thingys that are then connected in series that sums the wattage but maintains the ohmage? i.e., 1- 32 ohm 10 watt parallel pairs + 1- 32 ohm 10 watt parallel pair connected to each other in series equals 1- 16 ohm 40 watt network? Can I infer that while parallel circuits halve the resistance and sum the wattage, series circuits maintain the resistance and also sum the wattage? That would make sense out of using 4 resistors of 32 ohms 10 watts each to achieve a circuit resistance of 16 ohms with 40 watts power handling. Am I getting warm? Now, highly verbal lowly math person that I am, let me try this parallel/series thing with the nicely visual drawing in front of me. I imagine schematics have been around a long time and I really should learn to read one before I die. After all, I managed to read and understand the discourse between Newton, Linus and Hook in the "Transactions of the Royal Society" in the original script where all the S's looked like F's! I feel like Linus, unable to understand that Newton has invented a new branch of physics to explain the refraction of the light into it's spectrum so I fall back on what I do know and posit a little guy, a "homonculous" that does the job. But I digress. It looks as though parallel in the schematic represented by R1 and C1 is joining their respective leads to each other with the bodies of both elements lying side-by-side. 2 resistors are lying on the sand at the beach with their feet and hands joined. Kinky, yes? That's what I did with my 1- 16 ohm resistor and 1- .47uF Cap. Conversely, then, connecting two elements in series would be like links in a chain, verdad? Now the beach blanket resistors are joined at the hands only with their feet stretched out in other directions, who knows wh…
creator: BillEpstein
date: 2001-12-22T10:50:40-00:00

some component calculators
type: item
description: Hi Till, This page has some online calculator that you are able to enter the values and presto chango, your math problems are solved. Hope this helps you out Bill http://www.citlink.net/~bhamre/A_Electron/Electronic_Calc.htm
creator: bmar
date: 2001-12-22T13:32:26-00:00

Kama Sutra Series/Parallel
type: item
description: When two equal value resistors are connected in parallel, the resistance is halved and the power handling is doubled. This is largely because there is now two current paths, and power dissipation is split between them so capacity is doubled. When equal values are connected in series, current is now reduced - cut in half. This also means that the voltage across each resistor is made 1/2. So combining these effects, you now get 1/4th power across each series component that you would have had if the component were connected by itself.
creator: Wayne Parham
date: 2001-12-22T16:48:34-00:00

LIVE NUDE PARALLEL GIRLS! GIRLS! GIRLS!
type: item
description: I understand now. 2- 16 ohm 10 watt resistors joined in parallel equals 8 ohms 20 watts. 2 sets of these parallel pairs joined IN SERIES equals 16 ohms 40 watts. Parallel halves the resistance and series doubles it. Both sum the wattage. This so cool. Now for the crux of the issue, the main event, the big deal: aside from power handling, does 8 resistors comprising R1 and R2 sound any different than 2 resistors? Are we doing anything besides enriching the people that wind the wires and pour the ceramics? After tomorrow night, I hope, the Theatre 4's will see a maximum 3 1/2 watts with the newly constructed Paramours running flat out.The construction is done and tomorrow I will be breathing solder fumes non-stop! Something like Annie Lennox or Los Fabulosos Cadillacs might push that many watts. Can't wait to see the blue glow of those great big 2A3's. Wayne, this has been great fun, this old dog thanks you for the new tricks. Series-ely!
creator: BillEpstein
date: 2001-12-22T20:50:18-00:00

Re: LIVE NUDE PARALLEL GIRLS! GIRLS! GIRLS!
type: item
description: At very low power levels, I wouldn't expect any difference. But as power levels are increased, the smaller resistors will get hotter which can cause their values to shift at the least. When they reach their limit, they can start to make thermal noise and eventually burn open, possibly damaging other nearby components. I've seen heat from power resistors burn through a fiberglass circuit board.
creator: Wayne Parham
date: 2001-12-22T21:42:17-00:00

Re: LIVE NUDE PARALLEL GIRLS! GIRLS! GIRLS!
type: item
description: Till, Solder, Solder, Solder; Listen, Listen, Listen; Sleep; Listen again; then post initial review!!! I'll be waiting! Garland
creator: Garland
date: 2001-12-23T18:35:44-00:00

Hey Garland! Cut me some slack!!!!
type: item
description: There's 2 of these suckers. 2 bases, two plates to paint, double all the parts with those itzy little screws and washers. I'm on page 27. Just finished connecting the 2 green wires; one to B4 and 5, the other to B9. Sound familiar? And except for the ground plane, all the wire is stranded, all those little bits wanting to head off in some other direction than what you intended. Jeepers! It's looking like Wednesday to finish. Maybe I'll stretch out the fun for the 12 days of X-mas.
creator: BillEpstein
date: 2001-12-23T22:56:50-00:00