Quote from: g1 on October 26, 2025, 10:55:07 AMThe most standard, tried and true method is a pad/attenuator at the input; either using 2 input jacks or a switch.  Usually labelled Lo and High, or passive/active.
It is still the most common method you will find in use today.

That's a good idea, but I can't imagine any electric guitarist saying "Hmmm... perhaps I should plug into the 'Lo' input, as I wouldn't want to overload the front end of this fine amplifier".  Well, unless they're playing Jazz maybe...

QuoteIs there a particular reason you do not want to use this method?  Perhaps trying to address any shortcomings would be easier than trying to 're-invent the wheel' so to speak.

Because I'm designing (tinkering, really, if I'm being honest...) a preamp using 3 stages of MOSFET amplification as the dirtifier, and I've found that by keeping the intrinsic gain of each stage low, but boosting the front end, I've got some deep and tasty dirt with much less of the noise that MOSFET circuits are infamous for. I want that front end boost to be as squeaky-clean as possible in order to keep it's own distortion artifacts and harmonics out, as op-amps can sound pretty nasty when you overload them.  After a few pickup experiments, I realized that different varieties of pickups can have huge output differences, so I wanted an easy way to limit the input without simply building a compressor as the front end. 

Maybe I'm over-thinking it, and the only time someone else other than me will ever be concerned is if I build one for a friend, and that's fairly unlikely.  I'll put the schematic up here when I get all the bugs worked out and we'll see what happens.

So after further review after initial further review this initial assessment was possibly correct 

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I just don't understand why it's angled/tapered like a wire stripper 

Also my "speaker wire" is solid that might be a problem 

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A deep dive into the plethora of rusty crap in my garage produced these

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So I proposed this

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So it looks like I need to keep diving because I guess I still need some that just have a normal hole that I can use on the insulated connectors

If I wanted to simplify it by excluding the gain and tone pots? I want to make a tiny version with  3" speaker

I'm trying to get organized so I can connect devices to speakers and stuff

I ordered some connectors and these are a little bit big

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Then I tried these and they were REALLY TIGHT

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I thought maybe they were too narrow and I needed something in between but after further review it looks like the red ones are wide enough maybe the rolled part is tight

Meanwhile what type of pliers are you using to crimp these guys 

I'd like a nice tidy secure connection but it's not some needed like for military 🎖� 🪖 aircraft 

Thanks guys 

I know it's not much but in the meantime I still need to do stuff so I think I will try to flip that board over and reflow TR 201 (or remove and test and attempt to identify then reflow )

Also I can remove that green capacitor that looks cracked  and try to see if it has any markings on it so I can replace it.

I left it on with signal last night for about an hour and it would modulate for a while then cut out then after being quiet for a while it would come back on then repeat.

So I'm guessing that something is heating up and shutting down then cooling off and doing it all over again.

Also I noticed one of the binding posts somebody unraveled it but put it back.

Providing power and requiring it are 2 different things.  It sounds from that quote like a question was asked whether the DI can provide power (to something else), it can not.
It requires power, as all active devices do.  That can be provided by a battery, DC supply, or phantom power from a mixer.

I have located a schematic for the MPA-201.
As it is a dual channel amplifier you will have to take anything on it with a grain of salt.
The power amp looks as it may be the one that you have.
Although the component designators will most probably be different.
The regulator circuit appears to be a simple 15 volt zener diode.

Quote from: g1 on October 30, 2025, 03:42:57 PMAny of those supplies should work fine.  Sounds like the Radial box takes that power and turns it into whatever it needs anyway.
Yes, the phantom power box goes between the DI and the mixer.  And it should do a better job than a passive type would do.

Thanks G1 -

I have done some testing today with the Radial.  When going into a mixer with no Phantom Power, it will not pass a signal.  But testing on a second mixer with phantom power works just fine. 

I ordered a 48v Phantom supply and it should be here tomorrow.

And as an FYI, the LR Baggs Align Series Active DI works with a 9v battery and 9V external supply. As explained to me (on the LR Baggs Support Page), "The Align DI does not provide power of any kind. It will run on Phantom Power from an amp or mixer, via the XLR output on the DI. If Phantom Power isn't available, the DI will default to DC power. If Phantom and DC are unavailable, it will default to battery power."  That is somewhat confusing - on the one hand the statement says the Align does not provide power but later it says the DI will default to DC power.

LR Baggs Align Series Active DI