lumpy wafflesquirt
576 posts
Jun 07, 2012
10:35 AM
|
Has anyone else made their own IMT
I don't like the look of the in line ones so I am thinking of getting a transformer and mounting it in a box with an XLR socket and a short lead to a jack plug. I reckon having that length of IMT and then the XLR plug in the top is asking for trouble when the lead gets pulled a bit hard.
But where do I get the actual transformer from [UK and cheap] and what input/output impedance do I need for a PG58 and a Roland Street Cube. Neither seem to 'advertise' their impedance. I read on one site that impedance is an outdated way of measuring a devices input/output.
I also intend to mount two foot switched in the box to control the effects on the street cube.
----------
"Come on Brackett let's get changed"
|
tookatooka
2964 posts
Jun 07, 2012
12:07 PM
|
Good question LWS. Interested to see the answers to this one.
----------
|
Tuckster
1054 posts
Jun 07, 2012
12:28 PM
|
There was a time when studio mixers had transformers instead of electonic amplification for the mics. Really good ones weren't cheap. I suspect this to be true of impedence matching transformers,too. higher quality materials cost more money. I'm not sure what the ratio would be. Mic is 150-500 ohms?,,amp is 50k? I have no idea. Hopefully Greg H. will see this and chime in.
|
lumpy wafflesquirt
578 posts
Jun 07, 2012
12:49 PM
|
My reckoning is that if Maplins sell the in line IMT for £9.99 I ought to be able to source just the transformer for a good deal less. Or even enough less to make it worthwhile.
----------
"Come on Brackett let's get changed"
|
tookatooka
2965 posts
Jun 07, 2012
12:52 PM
|
Pity we can't get the specsheet for the Cube Lumpy. I wonder whether the MIC setting switches in an impedance matching circuit for mics seeing as the other options are for guitar inputs which must be high impedance. I find the MIC setting needs to have the volume cranked up rather high. The R-FIER setting with a mic is louder but more distorted than I'd like.
----------
|
5F6H
1231 posts
Jun 07, 2012
12:58 PM
|
Maplin do a self contained unit with connectors for £9.99.
Transformers for current Shure microphones like 520DX, 565 & 585 are avilable through your local Shure dealer. These will be more expensive.
Search RSWW, Farnell also...
Your PG58 is "low" the amp's input is "high" it's pretty pointless advartising specifics because they match over quite a range...you could, if you wanted, add an additional transformer to a Hi-Z mic.
----------
www.myspace.com/markburness
http://www.facebook.com/markburness
|
jimbo-G
128 posts
Jun 07, 2012
1:36 PM
|
i got mine from maplin aswell, you could get XLR to 1/4" jack for the top so if it does get pulled it will just pop out the 1/4".
If i remember correctly you could use z=(R squared + Xl squared) to the power of 0.5 to get the impedance but i could be wrong. that might just be for a inductor and resistor in series.
|
lumpy wafflesquirt
579 posts
Jun 07, 2012
1:37 PM
|
@5F6H what will I be looking for on RSWW or Farnell?
@Tookatooka I find that most of the settings are OK with the Lumpophone [600ohms] but a couple need the gain turning up. The mic setting is fine, it's the settings to the left hand end [cube isn't next to me] which need the gain upping.
My plan is to use the PG58 so that I can put it in a stand and use a [modified] harplock to play handsfree and then bash the Cajon.
----------
"Come on Brackett let's get changed"
|
5F6H
1232 posts
Jun 07, 2012
3:20 PM
|
RSWWW & Farnell ...don't bother if you're looking for cheap, RS have an ideal one...£35 + delivery! Maplin is still looking like your best bet for "cheap"...not that I think cheap is what you should be aiming for (buy the Shure A95uf).
Also checked out Studiospares for passive DI boxes...all more than the Maplin xformer. Cheapest I could find was £4.95 but it is jack to jack, suspect unbalanced in & out (no good for PG58....unless you rewire a cable XLR balanced to 1/4" unbalanced...which means a new cable, or butchering an old one...what you gain on the swings you lose on the roundabouts!).
----------
www.myspace.com/markburness
http://www.facebook.com/markburness
|
