+1 to both...
Measuring accurately to the 10th of an ohm between the two may not be the easiest. Try a few turns and see what it does for your own knowledge. If you find that too many turns has too little a change, and you're still worried, count turns from click to click and center.
Also adding to the previous... if you can't get to the bottom of the board, or just don't want to since they're mounted already, measuring across R3 and R4 is an option.
Measuring accurately to the 10th of an ohm between the two may not be the easiest. Try a few turns and see what it does for your own knowledge. If you find that too many turns has too little a change, and you're still worried, count turns from click to click and center.
Also adding to the previous... if you can't get to the bottom of the board, or just don't want to since they're mounted already, measuring across R3 and R4 is an option.
Anybody know a source for IRFP240s and '9240s?
I fried R13 on the left channel. I got a little hasty and careless while doing the biasing back-and-forth, and watched in horror as my meter showed 1V, rapidly climbing. Then smoke, so I shut it down. Fuse didn't blow. Right channel plays fine, so I'm anxious to hear the stereo version.
I've had the F4, F6 (stock, not DIY) and Aleph J, so I'm kind of working backwards vis-à-vis other folks' order of selection. So far, the F4 is king, but it's also a PITA if you don't give it enough voltage swing.
Edit: forgot my ACA, which I'm thinking of upgrading with some IRFP150s. Big assumption there, "upgrading".
I fried R13 on the left channel. I got a little hasty and careless while doing the biasing back-and-forth, and watched in horror as my meter showed 1V, rapidly climbing. Then smoke, so I shut it down. Fuse didn't blow. Right channel plays fine, so I'm anxious to hear the stereo version.
I've had the F4, F6 (stock, not DIY) and Aleph J, so I'm kind of working backwards vis-à-vis other folks' order of selection. So far, the F4 is king, but it's also a PITA if you don't give it enough voltage swing.
Edit: forgot my ACA, which I'm thinking of upgrading with some IRFP150s. Big assumption there, "upgrading".
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Depending on how many you want... whether you want them matched... enough to match... etc...
The store here.
Swap meet here.
One of your other amps
Octopart.com is a great resource if your normal places are out of one or the other and/or if you're looking for a manufacturer other than Vishay.
Mouser (but with a short wait)
The store here.
Swap meet here.
One of your other amps
Octopart.com is a great resource if your normal places are out of one or the other and/or if you're looking for a manufacturer other than Vishay.
Mouser (but with a short wait)
hey madlads, goofballs, and greedyboys, question: have any of you tried driving a set of b&w 801's with an F5? the bower spec sheet asks for a minimum of 50 watts @ 4 ohms, so it looks like we may just barely squeak in. I am aware that it's accepted wisdom to dump loads of power into these types of monitors.
Might also depend on the size of the room. I tried driving my Maggie .7s with the F5 and it sounded great, but ran out of steam pretty early on the volume curve. Room 20 x 30 x 15 foot.
I'm now using JamJar KISS (60W class A, 240W A/B into 4 ohms) and it's entirely sufficient. JamJar CFA has the F5 topology, but I haven't built it yet....
I'm now using JamJar KISS (60W class A, 240W A/B into 4 ohms) and it's entirely sufficient. JamJar CFA has the F5 topology, but I haven't built it yet....
Wanted to get some feedback if these capacitors could work on a pass build.
A local electronics store has them listed at $20 each (for the large ones) but said I could have them for $12 and I could take 4 home for free to try out first. The smaller 10k uf ones are $7 and I’m sure I could get them for $4.
any idea of these would work without me needing to test/charge them first?
they have a lot of each of them… I was thinking of trying the 33,000uf caps first (4 total).
A local electronics store has them listed at $20 each (for the large ones) but said I could have them for $12 and I could take 4 home for free to try out first. The smaller 10k uf ones are $7 and I’m sure I could get them for $4.
any idea of these would work without me needing to test/charge them first?
they have a lot of each of them… I was thinking of trying the 33,000uf caps first (4 total).
Attachments
to set P3 mid point, match the resistance over R3 and R4 with amplifier off