New build for shop system
- Thread starter AngrySailor
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So I ordered some new capacitors to beef up the passive crossovers in the three way cabinets. I don’t have the board in front of me at this time but did get the list of capacitor values used.
Original caps:
26uf 100v
40uf 100v
4uf 250v
12uf 250v
I ordered closest I could get in non polar film caps which was
27uf
39uf
3.9uf
12uf (exact match)
All these caps are 630v
After plugging these values into some calculations I came up with the inductor values and the attached schematic. If anyone sees any errors please jump in as I haven’t ordered inductors yet! (The 4uf on the tweeter will actually be 3.9uf) for all that maters... I wrote it down wrong.
Original caps:
26uf 100v
40uf 100v
4uf 250v
12uf 250v
I ordered closest I could get in non polar film caps which was
27uf
39uf
3.9uf
12uf (exact match)
All these caps are 630v
After plugging these values into some calculations I came up with the inductor values and the attached schematic. If anyone sees any errors please jump in as I haven’t ordered inductors yet! (The 4uf on the tweeter will actually be 3.9uf) for all that maters... I wrote it down wrong.
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Just realized I overlooked something I shouldn’t have... Just to avoid confusion, these crossovers in previous posts are for the shop system, I planned to use the same crossovers (as I have spares), for the house speakers. Here’s the problem. With these cabinets I have two 8 ohm woofers... I can alter the woofer circuit component values to maintain the crossover frequency if wired parallel for 4 ohm. But now I have 4 ohm woofers and 8 ohm mid/tweeters... what would be best way to equalize the impedance? Or should I go back to the drawing board?
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- Halfbiass...Electron Herder and Backass Woof
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I think..., after changing the crossover component values in the woofer section, the only issue would be response? The two woofers wired parallel for 4 ohm would be louder than the mid/tweeter... depending how by how much, this may not be a problem as the mids and tweeters are very sensitive, I am usually dialing midrange down with tone controls and bringing bass up. I am wondering if something like an L-pad attenuation circuit would work, but the resistors would have to be pretty high wattage... Not really and ideal situation, but its stuff i have that I'd like to make use of...
- Joined
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- Halfbiass...Electron Herder and Backass Woof
- Joined
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- 74,877
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- Tagline
- Halfbiass...Electron Herder and Backass Woof
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Yes, the caps and inductors for the low frequency section would both have to be changed. 1.8mH and 56uf is what I came up with. The other option, as I have two spare sets of these crossovers, might be to use one with a single woofer/mid/tweeter, then use only the low frequency section of the other as a low pass filter on the other 15" woofer, then wire in parallel. Basically a three way cab paralleled to to a low passed woofer. change no values as each crossover would be seeing the expected 8 ohm.
The loudness issue, would be the added 3dB caused by a second driver and also would the amp not see 4 ohm load at those frequencies and 8 ohm in the higher frequencies. I know that speaker impedance in not linear and changes with frequency, just trying to get my head around this...
The loudness issue, would be the added 3dB caused by a second driver and also would the amp not see 4 ohm load at those frequencies and 8 ohm in the higher frequencies. I know that speaker impedance in not linear and changes with frequency, just trying to get my head around this...
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Well stay tuned into March because huge is what’s about to happen! Four new cabinets for the shop @ 20 cubic feet each, for a total of 8x18” subs. Also been thinking of what the heck to do in the house with the existing speakers from the shop which are moving inside. I’m no interior designer, but here’s a quick doodle of what I’m thinking for layout. Plan is to build a nice wood cabinet to house the vintage gear and storage for tapes and records... the couch will have its back to the living room window which was the only option to not block the window completely with stuff or have to walk around speakers to access the master bedroom... Mrs. AngrySailor is pretty accommodating, but that could change real quick if she stubbed her toes on a speaker...
6 subs filled the back of a long box pickup...
6 subs filled the back of a long box pickup...
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- Joined
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Was looking on crapazon last night at TV’s. I don’t watch much TV but will probably get another for the living room. Found an RCA LED 4K 75” for about $600 maple syrups... Seems 4K is cheaper than 1080 now but the next cheapest in a 75” (LG and Samsung) jumpsup to $12-1400. I really don’t need one that big but if it’s a decent TV for $600... makes a fella wonder though why so cheap.... anyone use any modern RCA models?
