L'Amp: A simple SIT Amp

No he means 150 mH better than 100mH, which is what I have told you by elaborating on what to expect in listening. However 150mH with more than 5A, you are looking 200+ euros. The thing with 195T5 is that comes at a great price from mouser.com.

And you are going to have much less distortion in 5A than 3A (but you have to cool better)
 
No he means 150 mH better than 100mH, which is what I have told you by elaborating on what to expect in listening. However 150mH with more than 5A, you are looking 200+ euros. The thing with 195T5 is that comes at a great price from mouser.com.

And you are going to have much less distortion in 5A than 3A (but you have to cool better)

Other than weight, cost, and chassis real estate, you could series two
195T5 chokes, 5 amps and 200 mH .

Rush
 
SIT Supremacy

I have been using SIT L'Amp self bias as my default Fullrange amplifier, where J2 and M2 clone for another OB setup. I just played with newly upgraded Aurel Bryan 8" in 75L BR box, after listening for 2 days then i decided to try J2 and surprisingly i did not expect what i heard, SIT wins all around compared to J2 especially how big the soundstage it can create. Different with J2 with smaller soundstage and left the WOW experience with SIT

so SIT + Fullrange combination is heaven for my ears
 

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Founder of XSA-Labs
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Since it is SE Class A, there is poor PSRR with this amp, so any residual ripple or noise in the PSU will show up in the speaker output as noise. So a very clean PSU will enable you to use this on a headphone. Something like a cap multiplier and CRC will work. Or a SMPS with some LC filtering could work as the mains 50/60Hz hum is much less. But usual linear trafo and CRC alone may have audible hum when using a headphone. I have used the LuFo Lite as a headphone amp and it’s quiet since I have a cap multiplier and it’s powered by a SMPS. I used a 20W 12v halogen bulb in place of R3 here. Build was way too bright and ideally a higher wattage bulb would have been better.

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Since it is SE Class A, there is poor PSRR with this amp, so any residual ripple or noise in the PSU will show up in the speaker output as noise. So a very clean PSU will enable you to use this on a headphone. Something like a cap multiplier and CRC will work. Or a SMPS with some LC filtering could work as the mains 50/60Hz hum is much less. But usual linear trafo and CRC alone may have audible hum when using a headphone. I have used the LuFo Lite as a headphone amp and it’s quiet since I have a cap multiplier and it’s powered by a SMPS. I used a 20W 12v halogen bulb in place of R3 here. Build was way too bright and ideally a higher wattage bulb would have been better.

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Superb

Thanks alot for the tips

Really appreciate it

So L'amp is good to load with 300ohm headphone?

Regards
 
Founder of XSA-Labs
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It depends on how sensitive your headphones are and how loud you like to listen. 300 ohm headphones are usually voltage limited since it takes higher voltage to drive current through a large impedance of 300ohms. Let’s assume you want to hit 110dB peaks and let’s assume sensitivity is about 97dB per mW (specs for Sennheiser HD-600). So you need to reach 13dB above 1mW rating. My estimates say that will take about 2.05Vrms into 300ohms for circa 12mW. The LaSIT probably has no problem reaching 2.05Vrms. So you are good if your headphones are 97dB at 1mW.
 
Since it is SE Class A, there is poor PSRR with this amp, so any residual ripple or noise in the PSU will show up in the speaker output as noise. So a very clean PSU will enable you to use this on a headphone. Something like a cap multiplier and CRC will work. Or a SMPS with some LC filtering could work as the mains 50/60Hz hum is much less. But usual linear trafo and CRC alone may have audible hum when using a headphone. I have used the LuFo Lite as a headphone amp and it’s quiet since I have a cap multiplier and it’s powered by a SMPS. I used a 20W 12v halogen bulb in place of R3 here. Build was way too bright and ideally a higher wattage bulb would have been better.

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What is the LC valie that you use?

Thanks in advance
 
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Mark Johnson does a good job of explaining it here

https://www.diyaudio.com/community/...-vfet-theseus-chassis-incl-thump-kill.379747/

It depends on your SMPS switch frequency but a filter that gets everything above 50kHz is usually good. I often grab whatever I have on the bench and work the values to get 50kHz or better. Typical value would be 0.33mH and 220uF and bypass that l with a good low ESR 1uF or 2.2uF MKP film cap is good.

Here is the filter used by Mark Johnson’s TubaV:
schematic1-png.999811

What is important is to make sure the inductor can pass the high current. Smaller inductors are often less expensive than bigger caps. So a 33uH inductor good for 20A (CoilCraft SER) and a 2200uF cap will have similar effect.
 
I have been looking for a preamp for additional gain with SIT, but find no time to build it. but i find this lovely made Whammy by @bluenote and he lives in the same island with me. additional bass boost really helpful to drive my Aurel Bryan fullrange.

now this is a lovely setup for Whammy + SIT L'Amp + Fullrange
 

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