That's great! 🙂
Now Nelson can add a line to the F5 article: "An amp that even a 6yr old can assemble" 🙂
Joking a bit, but that's really cool. Wish he further develops the talent and becmes better than his father. I have a 6 yr old too, but he's more interested in math 🙂
Regarding "caseless" amps, there's a certain minimalistic appeal in running electronics on just a piece of wood. Once you put them in a nice shiny case, they don't sound as good 😛
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Awesome! Makes me feel a little bad that I waited until our daughters were 9 or 10 before I had them soldering their amps together.
MEPER: thanks for the details on the regulators!
MEPER: thanks for the details on the regulators!
how would be the harmonic profile (H2 vs H3 and phase) using 2 mofos bridged for each channel?
Input form each mofo per channel fed by the + and respectively the - output of a balanced DAC
In bridged mode with balanced drive maybe 2nd harmonic might be reduced? Slew rate doubles and power is 4x more though if everything is idea. That’s how single rail 12v Class D amps operating in BTL get something upwards of 25wrms.
Hi guys,
Do you think this will work, replacing L1 with an output transformer, and removing C2 / R5 out of the circuit.
If yes, what would be the required primary impedance, primary DCR, primary inductance?
Do you think this will work, replacing L1 with an output transformer, and removing C2 / R5 out of the circuit.
If yes, what would be the required primary impedance, primary DCR, primary inductance?
An externally hosted image should be here but it was not working when we last tested it.
you need a gaped transformer to avoid saturation with DC
coming back to bridged MOFO do you think that H2 will go lower and maybe H3 increase?
the advantage of bridged mofo is to use an output transformer without gape because the DC magnetic flux will be cancelled. No need for gaped transformer, just a 12+12v transformer like this input transformer can be omitted if feeding from balanced source (XLR) and using the MoFo bias network
coming back to bridged MOFO do you think that H2 will go lower and maybe H3 increase?
the advantage of bridged mofo is to use an output transformer without gape because the DC magnetic flux will be cancelled. No need for gaped transformer, just a 12+12v transformer like this input transformer can be omitted if feeding from balanced source (XLR) and using the MoFo bias network
If I were doing a transformer coupled MOFO, I would do a 1:1 transformer with the same primary inductance, same current capabilities as the inductor it replaces.
I edited this to second the gapped transformer requirement.
HTH
I edited this to second the gapped transformer requirement.
HTH
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maybe only need of the secondary windings of the transformer and put the speaker on the source of the mosfets
transformer should be EI core to avoid saturation by little current imbalance
but VA and voltage of the secondary?
transformer should be EI core to avoid saturation by little current imbalance
but VA and voltage of the secondary?
It will probably be difficult to find a transformer which can transfer the signal better than a high quality capacitor?
Marconi118;
The answers you seek to the push-pull amp you displayed are in the Zeus Amp thread and the Zeus Amp web pages.
Jolntsai;
For a SE transformer, I would consult a transformer manufacture.
All output transformers are a compromise. Having low impedance drive is a big plus.
One thing for sure, its going to be heavy if you want more than a few watts.
I would guess 20% more than the inductor required for the equivalent MOFO.
HTH
Can you all hear a bit of white noise from the tweeter when a preamp is connected to MoFo and the ear is 3-4 cm from the tweeter (94 dB tweeter in my case)? …..with volumen turned down? with MoFo only connected with shorted input the white noise is almost inaudible but with preamp…..in my case BA3 pre the white noise is a bit more audible. At a distance of 30 cm from ear the noise is inaudible. I use a Khozmo 50k shunt attenuator for BA3 pre. So a 50k resistor is always in serie with signal and with 47 k Rin of BA3 pre the signal is only half even at full output. Step 0 is gnd. Step 1 is -60 dB and I am able to hear the music through the white noise with ear close to tweeter. So I guess I should be ok regarding noise? …..or what is normal? …..I hear no "buzz or hum". Would I be able to hear a bit of white noise from tweeter even with the most expensive Pass Labs amps connected?
I think I need the gain from BA3 pre for MoFo. At Listening position 3-4 m away from speaker the volumen knop has to be from 1 o'clock to 4 o'clock for normal listening level depending on how loud the recording is and how your listening mood is and time of day etc.
Think….or hope I am ok. After 1-2 hour of warm-up.....the white noise in tweeter is audible only with ear 15 cm from tweeter or so. It probably also depends of the gain of the ear 🙂 …..my tweeter has waveguide so it also amplifies the noise a bit.
Would one of you gents be so kind as to point me to the part number for those little blue boxes with the screws that are soldered to the MoFo pcb for attaching power and signal leads, I'm not sure what they are called as have normally just soldered everything?
Cheers
Jamie
Cheers
Jamie
Try make a google search for Euro Terminal Blocks.
3P Single Row Euro Terminal Block Connector Screw Connection Matte Sn
3P Single Row Euro Terminal Block Connector Screw Connection Matte Sn
Finally, MOAMOFO playing in stereo. Dual mono setup with independent 37v @ 4.5amps provided by a pair of Antek AN-3232 powering JK-MrEvil Cap Mx's, and voltage gain provided by Aksa-Lender Melbourne preamp. Good for 50wrms into 6.8ohms. Quick test at loud levels and sound is not congested - nice sounding and can get loud. Now also fitted with Noctua silent PWM fans pushing air through CPU coolers to maintain air temp at 45C.
