Everything posted by 95Honda
-
Amplifier output testing
As long as your meter actually reads RMS, this will work. You could also take the Pk-Pk measurement with your scope and do the math... Having a battery as a power source is tough because it is unregulated. Try and do the test quick before the battery voltage drops too much. Also try and do it quick before those dummy loads heat up. If they do (they look like the Partsxpress ones) mount them to a metal plate or heatsink. For high power tests I usually had them sitting in a 5 gallon bucket of cold water. (clean water isn't really conductive at all)... Again, like you stated, check the resistance of the load. The tolerance may not be too tight on those... And yes, follow the tips above and you are doing it right... Have fun....
-
Flatlyne Motors
I doubt they have shorting rings, being underhung with a short winding length. I could be wrong....
-
what your favorate old school amps
My cousin is still running 3 of the original Rockford Power 1000 Mosfets (he bought brand new) in his Chevelle trunk powering 6 Tempests... Old school...
-
what your favorate old school amps
Phoenix Gold A44 Majestic 1000 Watt Soundstream D200
-
Sp4 4th order or 6th order
If you don't have the experience, I would suggest a standard 4th order vented, alot less to mess up...
-
4th order on a xcon 10
The 4th order bandpass will (hopefully, if you design right) have two F3 points (-3bd), a low one and a high one. They will be above and below the actuall tuning frequency of the vented section. You need to model to see how this works. But, the tuning of the vented section will generally be higher that that of a 4th order vented with similar low end F3.
-
Home theater box design
That's pretty cheap!
-
IB'n my room?
Bose don't sound very good. All marketing hype... Most of thier towers use garbage 99 cent Chinese junk cone tweeters... I have re-coned 3 of thier flagship 901 sets over the years. Every set sounded like shit, even with the Bose EQ and everything set up right... I don't know how people can live with them honestly.... Look into a kit from Parts Express or Madisound. Check out Zaphaudio.com also. The full kits from the first two vendors are a piece of cake to build...
-
Proper "break in" ???
I don't want any money. I will be glad to help you out, just need to give me a few days... Busy as hell... PM me dimensions...
-
Proper "break in" ???
If your overall goal is loud and low (and "hitting all the notes) a standard 4th order vented will do a better job. You will also have better control of the driver and greater mechanical power handling above system (4th order) resonance. If you overall goal is transient response and flat impedance (but do not care about maximum ouput) I would go with a T-line. I would also make sure it was stuffed and adjusted for the flatest impedance possible. I have built maybe 20 or more T-lines, only a few have gone in a car and they were for single smaller driver installs that did not need a lot of overall output. The T-lines I built for the house were all big, heavy and had great low end response and I really liked the way they sounded. I tuned almost all of them with impedance measurements and had to adjust the stuffing on all of them. This isn't easy. I normally left one whole side of the box un-glued so I could take it on and off and adjust stuffing. My big Sono-tubes were easy because I just kept adding more or taking more out from one end. The last set I built for the home used a pair of 8" Focal 8V416Js per cabinet (8") and they were about 5' tall, 5' deep and 1 foot wide ans weighed an ass-ton. Like I said, just think about your overall goals because you are the one who will live with the enclosure when it is all said and done, and your satisfaction is #1 priority. Not someone else's satisfaction of seeing a neat complex enclosure...
-
Sun Down SAZ-1500D V3 Feels Weak
You need to understand what the gain setting on an amplifier does. It does one thing and one thing only, it sets the overall voltage gain of the amplifier. It doesn't set output power, it doesn't set maximum output, it doesn't limit anything and has nothing to do with clipping. When you set the voltage gain you are setting a ration (in db) between voltage input drive and voltage output. Current and power will vary with load impedance. So, what does this mean? That gain knob is arbritary, and usless in most cases. If it wasn't there (like most home amplifiers) the voltage gain of the amplifier would be whatever the overall design was intended to be. And that is how a car audio amp is designed to work before they stick the voltage gain adjustment pot on the amp. It really doesn't make any sense to have it anywhere other than full clockwise if you have a single amp and adjustable sub level from your HU. If you have multiple amps, it helps with matching, thats about it. So if you understand that it only sets the voltage gain and nothing else, you'll see why making a comparison about gain and HU level in comparison to overall output is pretty meaningless...
-
Proper "break in" ???
OK, just want you to understand a few things. And please, understand that I have been building T-lines since the last 80s, and anyone who says otherwise is full of you-know-what... #1, T-lines will never be as efficent as a 4th order vented alignment over the average pass-band. In fact, their efficiency is overall low, comparable to a sealed alignment in all but the last octave. #2, The only advantages of a T-line are flatter impedance, decent low end extension (relative, but at an overall efficiency penalty) and decent transient response but you are giving up a lot in physical size... #3, You should really look at dampening your line. Undamped lines do not normally work well and you can cut the length down signifigantly when you dampen. Also, undamped lines can get peaky, and kill any SQ advantage you are seeking... #4, T-lines don't have a "tuning". In fact, quite the opposite. They are non-resonant and have a cut-off, not a tuning. This is also why they are relitively non-efficient. #5, look at the cross-sectional rations and thier relative differences. Pick a ratio and taper that will meet your goals. So, as long as long as you understand that you have been mislead about the advantages of a T-line as far as efficiency and output, press on if you want to give it a shot, just be objective in your goals. If your overall goal is loud and low, look elsewhere, a 4th order vented will do both better. If you are looking at low end at an output penalty, than press with a T-line...
-
Sun Down SAZ-1500D V3 Feels Weak
OK, you need to attribute the differences to the overall voltage gain of each amplifier, not power output. It is very misleading to other people who don't understand how this stuff works when you make erroneous comparisons like you did.
-
Home theater box design
How much are the Pinnacles?
-
Sun Down SAZ-1500D V3 Feels Weak
OK, quick question, does the Sundown get as loud as the RE?
-
Home theater box design
These are on sale for $100 a pair right now and will kill those Pinnacles... They are normally $250... http://www.parts-express.com/pe/showdetl.cfm?partnumber=300-464 BTW, I bought a set of Pinnacle PN-6s brand new in 1993...
-
Proper "break in" ???
Well, from the sketch, that is a T-line. Couple of questions, what is the line length and cross-sectional area? What are you going to stuff it with? My last question is, why a T-line? Most people don't understand that they are less efficient than a standard 4th order vented and only mildly more efficient than a sealed alignment. They definetly have the ability to be superior in transient response, but not in output. Have you started building it yet?
-
Outfitting a Dorm Room
Problem is, PA subs less the $500 a pair sound like garbage and are built with crappy cabinets and usually Piezo tweeters... You need to roll your own with the budget you have to get something decent...
-
Proper "break in" ???
If you truly have a T-line (no enclosure, only line) then be careful not to damage the drivers due to over-excursion... There is no break-in needed, unless you are trying to verify T/S parameters. Just play them sensibly and you will be OK.
-
A well thought out 15" Mayhem build...
Update. He upgraded the alt to a 300 amp. Still waiting on the install...
-
Outfitting a Dorm Room
Like I said HE10's would be the way to go. I am building a set of Hurricanes for my garage (HE10's + 18" subs in each cabinet) right now. 95db efficiency and healthy bottom end. A set would tear a dorm room down. Pair them with a 2KW Behringer amp and you'd have the whole thing for about a grand... PM me your email and I'll send you PDFs of the plans...
- Please Help An Old School Basshead Find My Long Lost Low Bass
-
Please Help An Old School Basshead Find My Long Lost Low Bass
Wow. I remember using a ton of the XTRs in the early 90's... Weren't those the blue dust cap for SVC and red for DVC??? I probably owned/installed 10 or 20 of them, lol... Those and the original Punch, Lanzars and Hollywoods, lol... Look at the T/S parameters of those subs. They weren't low end monsters... Low xmax, mid range Fs and qts that didn't lend well to tons of bottom end sealed without decent cabin gain. I think you will be much happier with what is availible now, especially for that last octave with a single sub. One of the newer 12s you are looking at has more displacment than any 15 a decade ago, and that is really what counts on the bottom octave. FWIW, we swapped out 6 JL W5 15s in a sealed wall in my cousin's 1972 Chevelle for some Adire Tempests about 9 years ago. The Tempests aren't anything near as good as what you are looking at. The W5's were almost a decade old when we did the swap. He picked up almost 10 db on the Termlab around 20Hz.... Food for thought...
-
Sa 8 ported am I on right track
What does handling 1000 watts have to do with anything?
-
Fuse rating for BC3500?
Well figure double what you already have then...