I am planning to use a couple of Dell laptop 65 watt adapters. 19.5 v 3.34 amps. They come with 7.4 x 5.0 mm connectors. Is there a socket I could buy that fits such a plug. I've looked at Mouser and other places but have not found anything.
Otherwise of course I could simply cut off the plug and determine which of the two wires is positive but I thought I would try to be neat and tidy.
ray
Otherwise of course I could simply cut off the plug and determine which of the two wires is positive but I thought I would try to be neat and tidy.
ray
If it’s a standard 5.5mm dia barrel connector you can find them all over the place. But it may be a proprietary Dell connector (skinny center pin, large dia outer barrel) then no.
uxcell 5pcs DC-099 Female 5.5 x 2.5mm Panel Mounting DC Power Jack Socket Connector Amazon.com: uxcell 5pcs DC-099 Female 5.5 x 2.5mm Panel Mounting DC Power Jack Socket Connector: Home Audio & Theater
uxcell 5pcs DC-099 Female 5.5 x 2.5mm Panel Mounting DC Power Jack Socket Connector Amazon.com: uxcell 5pcs DC-099 Female 5.5 x 2.5mm Panel Mounting DC Power Jack Socket Connector: Home Audio & Theater
I have cut off about 6 of those. You can wire it up with a standard 5.5mm barrel connector with strain relief if you want to use it amongst multiple projects. Always nice not to have a hardwired brick. No regrets on my part as I have no intention of using it with laptop anymore.
I will probably just use them for this project and use a white European terminal block. Simple enough.
ray
ray
Beautiful boards have arrived! Super quick from US to UK
Is a preamp with 15db gain (I figure that’s about 5.5v) enough to move these MoFo’s to action?
Is a preamp with 15db gain (I figure that’s about 5.5v) enough to move these MoFo’s to action?
Great!
That will get you about 4W with 8 ohm speakers, so it will depend on the sensitivity of your speakers, etc. MoFo enjoys a preamp with some gusto. If you turn the volume control all the way up and it still sounds soft, you need more gusto. 🙂
That will get you about 4W with 8 ohm speakers, so it will depend on the sensitivity of your speakers, etc. MoFo enjoys a preamp with some gusto. If you turn the volume control all the way up and it still sounds soft, you need more gusto. 🙂
I was able to get 26.8vpp out of MoFo (red trace) with The Aksa Lender pre with 22dB gain. This is with 19v PSU and 68mH choke.
XRK,
So 26.8v peak to peak is:
13.4v peak which is 13.4/sqrt 2= 9.14V rms which is (9.14) squared/8 ohms or about 10 watts RMS?
Best,
Anand.
So 26.8v peak to peak is:
13.4v peak which is 13.4/sqrt 2= 9.14V rms which is (9.14) squared/8 ohms or about 10 watts RMS?
Best,
Anand.
New MOT just arrived via eBay, same model number but comes in at 98mH and 0.98ohms DCR. I will be able to make a stereo MoFo now. Previous one was 67mH and 0.47R. How will this affect stereo balance?
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Nice! I have a pair of LL2733’s lying around. At least 100mH @ 3A with 0.85 ohms DCR (coils in parallel).
http://www.lundahl.se/wp-content/uploads/datasheets/2733.pdf
A CCS as the current sink may provide even better performance with advantages in PSRR & CMRR.
Still, should try it with a choke as the current sink as designed.
Best,
Anand.
http://www.lundahl.se/wp-content/uploads/datasheets/2733.pdf
A CCS as the current sink may provide even better performance with advantages in PSRR & CMRR.
Still, should try it with a choke as the current sink as designed.
Best,
Anand.
You get more power out with chokes. It sounds a lot more dynamic. The MOTs are nice and cheap under $30ea yet measure well and sound great.
Thanks for the sonic insight regarding chokes vs. CCS. I guess one should investigate both these possibilities further with measurements as well.
Regarding MOT, it would be nice if you could order a pair that measured the same! At least with Lundahl, I know that a pair will measure close but they cost $100 each iirc.
Best,
Anand.
Regarding MOT, it would be nice if you could order a pair that measured the same! At least with Lundahl, I know that a pair will measure close but they cost $100 each iirc.
Best,
Anand.
It’s very strange that the same model and size choke would have such a large variation. Maybe I go and remeasure. Something could have been off with that LCR meter. MOTs also have potential for costing nothing (as scrap).
Hi X,
The differences may be in the core laminations, the gap, and the turns and the winding gauge. More inductance will not affect midrange and top end; but it will make more bass, which because it is not directional may not make perceived differences in balance.
The 'dead loss' on these inductors is the DCR. 0.98R means that with 1.7A you will throw away 1.67V from your supply; so if you have 27V supply, you are effectively working only with 25.33V, which reduces your headroom but is not too much of an issue if you can deal with the heat from the active device.
Ciao,
HD
The differences may be in the core laminations, the gap, and the turns and the winding gauge. More inductance will not affect midrange and top end; but it will make more bass, which because it is not directional may not make perceived differences in balance.
The 'dead loss' on these inductors is the DCR. 0.98R means that with 1.7A you will throw away 1.67V from your supply; so if you have 27V supply, you are effectively working only with 25.33V, which reduces your headroom but is not too much of an issue if you can deal with the heat from the active device.
Ciao,
HD
