XLR out or mic or DI box

I don't want to hijack my own thread but I have a fender deluxe 85 with a pre amp out is that the way to go or is headphone out better for my 2i2?View attachment 103320

Can't find a schematic for the DL85 and the manual doesn't help (guitarists cannot understand voltages it seems!) but I would guess a Pre amp out would be around 0dBu, 0.775V to one volt and probably go a bit higher, should be fine for a F'rite line input.

Headphone outs tend to be lower than true line outs voltage wise but of course have a higher current capability. They are also "stereo" and that can be a problem with a balanced input.

Dave.
 
Thanks
When do you need to use a passive DI box for recording?

Is that a general "don't know" question? Well, it is true that now AIs virtually all come equipped with at least one high impedance input specifically designed for passive guitar (though there is no reason why you cannot stuff a synth or almost any other "lineish level" device in there) there is not that much need of a DI box for the home recordists but, there are other factors..

A passive, transformer based DI will add a certain "flavour" to a guitar, mainly because of the technical shortcoming of a passive DI! Even a very high quality active DI, going into a mic pre amp could give a different, possibly pleasing change of tone to the HZ input.

The DI box actually came about (AFAIK) because guitarist wanted to get an instrument "off stage" and into a mixing desk for FOH PA or/and recording. There is also a technique using two passive DI boxes back to back* to get a guitar in a control room to feed and amp out on the studio floor.

*I have come across peeps that think you need two DI boxes for re-amping? You don't.

Dave.
 
I am sorry for the delay but the transformers must have come from China!

See, having banged my drum saying an XLR DI out on an amp should be balanced and at mic level (shall we say -40dBV 10mV?) and really should be transformer isolated I thought I should put my money where my mouth is? A whole tenner! That tenner amazingly bought me TEN 1:1 transformers, wee things, 14x10x5mm pri and sec resistance around 140 Ohms (will do pikkies later)

I generated 1kHz at neg 6 in Samplitude (see wavgen) and you can see the harmonics are almost 100dB down for the third and falling and no second harmonics.

That signal was passed through a ZED10 mixer from the laptop and some 0.5V fed to a traff primary. The traff output was loaded with 6k8 being a little less kind than the normal 10k.

Sec' out was recorded via NI KA6 into a desktop and you can see the resultant spectrum

'Oribble innit! Well not really. Third is the highest harmonic and that is 60dB down on 1Khz. For such a cheap transformer I reckon that is not at all bad? Yes, distortion at 100Hz is going to be worse (my next test) but consider, if use to deliver a MIC level output the signal level will be a good 30dB below half a volts and thus distortion proportionately less. ANYWAY! Bit o second harmonic adds 'warmf!"

I hope to be able to do more tests. Distortion at lower frequencies at 'mic' levels and, if I find the time and energy some for of distortion device driven frm an amp dummy load.

If anyone this side of The Pond wants one to play with I can donate four* say. Just PM an address. No charge.

*I meant one EACH! (top pic is output)

Dave.
 

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