TM019 transformer for reamp box

[m_charles]

Hi there.
After doing some research, it seems to me that a cheap TM019 (42TM019) transformer which has a 10k:600 would be suitable for a cheapo diy reamp box. However, I have never found a reference indicating this is a suitable transformer. Wondering if I'm missing something here.
Any thoughts?
Thx in advance for any help.
Spec sheet:
https://www.mouser.com/ProductDetail/Xicon/42TM019-RC?qs=LQJGOuQCHKQk%2FaBX9yNCGw%3D%3D

[FiveseveN]

300 Hz?  Its performance is going to depend on what's driving it anyway.
If you'll excuse my unabashed prejudice against "reamp boxes", may I ask if you have ground loops or other noise issues if you connect the interface directly to the amp? I'm assuming that's what the box is for.

[m_charles]

The impedance coming from an interface is much different than a guitar hitting an amp. So if you have a raw guitar track, (often a raw track will be recorded when using an amp sim "in the box", meaning in the computer).
A reamp box is used so the signal coming from the interface will be similar to the signal coming from a guitar. This way the amp will react as though someone were actually playing the guitar plugged in.
It's not that putting a signal into an amp without a reamp box wouldn't work.... it's that the sound won't be the same (and often terrible).
Try it sometime, you'll see. I've done it and it sounded like dookie.
doesn't have anything to do with ground loops or noise.

[MikeA]

I'd give it a try.  I used 42TM018s (10k/10k but with the same specs as the -019) for isolation in a buffer/switcher, and driven at unity gain, the response was flat up to 10 kHz.  I didn't record the low end response but it worked well enough.  And the price was right.  You can see a similar use at http://www.geofex.com/FX_images/TransformerSplitter.pdf

[FiveseveN]

Try it sometime, you'll see.

But I've been doing it for at least a decade  And I've yet to find someone who can explain what a "reamp box" is for, but when they try it's usually something about that scary word that implies trigonometry and imaginary numbers: "impedance".
If I understand correctly the issue is that "an amp" behaves differently (unpleasantly so) when driven by the low impedance source of an interface output. Does it have the same issue with any other low-Z sources like active pickups, buffers, wireless receivers, effects?
I assume it's a tube amp. Doesn't it have a grid stopper at the input that's at least on the order of a passive pickup Z?
Is there something I'm missing? How does this use case picture from Radial themselves make any sense? Un-buffering a signal to send it through 3 buffered-bypass pedals before the amp?!

[moid]

I don't have the technical knowledge to tell you how a reamp box works, but I have an Art Dual Z Direct Passive https://artproaudio.com/product/dualzdirect-dual-professional-passive-direct-box/ box and it works really well for what I use it for (and it's cheap, or cheap in the UK at least). I often try to record at least two channels of guitar - one dry signal, the other wet, and then later on I can decide to run the dry guitar through some different effects pedals if I decide the original selection didn't work in the mix with other instruments. I play the dry signal through my DAW to my Scarlett 6i6, whose output goes into the reamp box. The reamp box goes into whatever effects pedals I want and that returns to the Scarlett's input sockets and back to a recording track in my DAW. When I didn't have the reamp box I had use another pedal (Pigtronix philosopher's tone) as a limiter to massively lower the volume coming out of the Scarlett or any audio going into effects pedals would be stupendously loud and even the gentlest acoustic guitar would sound like Keiji Haino with tooth ache flailing a jet engine with a contact mic... and even with the output of the DAW on low and the philosopher's tone on near minimum volume, the resulting guitar tone sounded like a lot of frequencies were missing... it wasn't good.

So if you need to re record dry audio through different effects in a loop that starts with a PC and ends with one, I think they are indispensable. I've no idea what else they are supposed to be used for!

[FiveseveN]

even with the output of the DAW on low

What is "low"? Doesn't the fader go all the way to -∞?
What is "cheap"? If you need attenuation surely two resistors or a pot are cheaper than a transformer or DI (transformer in a box).

[moid]

You'd think so - but when you set it too low the audio cuts out entirely, and when adjusted to actually produce audio (slightly higher level) the audio you hear is far louder than you'd expect (or want in my case). It doesn't seem to fade in as you would expect. I don't think the software is the issue (I have the same problem in three different DAWs), so it's either the Scarlet or something else, and having tried to output audio straight from a soundcard (avoiding the Scarlet) I get the same deafening issue... so it could be something physical in my PC...but I don't know and haven;t been able to figure it out and this device stopped me wasting time and getting angry! Regarding cheap well I bought this years ago and had no idea how to fix the problem I was having and found someone recommending this device for the same issue i had, and it was (I think?) £30... so yes, a lot more than two resistors and a pot, but I didn't know how to solder in those days

[MikeA]

But I've been doing it for at least a decade  And I've yet to find someone who can explain what a "reamp box" is for...

From the manual for my Pigtronix Keymaster, which they originally called a Reamp Effects Mixer:

"In the studio, the Keymaster provides producers with a simple and
effective solution for ReAmp applications. The Keymaster converts
balanced, line level signals from the mixing desk to effects friendly levels
and then returns the signal back to balanced output or buffered ¼"
outputs for a guitar amp."

So it follows that a reamp is for sending line level balanced signals to instrument level unbalanced FX and bringing them back. Board -> FX -> board.  Or optionally let the signal roll on after the FX to an amp and recording it again thru the amp.

[FiveseveN]

I don't know and haven;t been able to figure it out and this device stopped me wasting time and getting angry!

I'm glad you found it useful and I'm sure many people do. It's just that buying a product to fix an issue you don't understand is not very "DIY".

So it follows

First of all, no. Most have a single transformer for the line to instrument level conversion job. The thing that goes the other way (instrument to balanced line) has been called a Direct Injection box since the '60s. And I'm betting people have been using passive DIs "in reverse" for just as long.

for sending line level balanced signals to instrument level unbalanced FX

Let me rephrase my question: why do you need a transformer for that?