Topic: Hi vs. Low Z swtch on digi mod UA-5

[LeftoverSammy]

Hey Now,
While taping the ABB yesterday here in Puyallup, WA I noticed the
Hi/Low Z switch on my UA-5 was pushed down to Hi Z by accident for
several songs. I promptly changed it back to Low Z and carried on.

My question is with the digimod UA-5 is the Hi Z inactive when using XLR (mic-in) regardless if the Hi or Low Z is engaged? Does this really matter?
   
On Doug Oade's website it states with the digi mod that the TRS jacks are disabled with this digi mod. Aren't most Hi Z jacks 1/4" TRS? Does having my mics plugged into the mic-in via XLR (warm mod) and have the Hi Z switch engaged make any difference??

After listening to the tapes I hear absolutely no change to the sound
(I remember exactly when I made the change back to Low Z). Can
anyone out there clue me in on this? Has anyone else accidentally
engaged this switch by accident also? What were your observations??

The impedance of my mics is 300ohms I believe.

I used the tape the show the following gear:

Nakamichi CM701's (ORTF) > Luminous Audio PS > MX-100 (2 channel) > mic-in (wmod) UA-5>
D8
DFC/FOB 14th row @ 10ft

The show sounds really nice so I am happy with my efforts, however I
still would like to know if I have to worry about this in the future. Its easy to accidentally engage this switch if you have anything resting on the UA-5.

Thanks all for the help!
Peace,
LoS

[jewgrass]

The 1/4" inputs are disabled with the preamp mods, not the digi-mod.  If you're using the XLR inputs, that switch doesn't come into play.  I've done the same thing with that swich using the xlr ins and there was zero difference.  hth, John

[LeftoverSammy]

Thanks John,
That was my impression as well. Thanks  again for the correction as well about the pre-amp mod. It is the preamp mod that disables the 1/4 mic in.

LoS  

[Kindguy]

The first show I taped with the warm UA-5 I had the hi Z on. Just because I got the UA-5 about 30 min before we left for a show. Worked just fine. Wasn't till I got home & noticed the manual said run it low Z.

T+ for the question. I've been curious about it since.

[DCDireWolf]

I taped a multiple band show the other night when i first noticed the high z/low z button.

I taped the first band like I usually do, on low z.

However, for shits and giggles, i taped the second band on high z.  Once I pushed the button, it had an immediate impact on my level readings.  I was monitoring my levels thru the svu-2 as well as a MD because it's easier to read a MD. 

As soon as i went high z, the MD levels went down and the svu-2 levels went way up, without any adjustment by me.  I had no idea which one to trust (should have trusted the MD with it's digital connection, rather than my svu-2, but such is life).  Ended up being scared I was now running too hot and recorded a very low show.

I run a warm mod ua5

fwiw.

[pfife]

It didn't matter on my W-Mod UA-5.

[hexyjones]

Its the equipment that you plug in that determines how the switch is set...

Guitars -  Hi-Z

Most mics with XLRs - Low Z - but some of those older Shure dynamic mics are high imp...

Low Z = ~200 - 600 ohms

Hi Z = ~ 10,000 ohms

Someone straighten me out on this is if I've misstated anything...been awhile...

[johnw]

I believe that the Hi-Z is only for the 2nd (R) input. At least this is what is indicated on page 11 of the manual. If you are using the XLRs, I don't think it matters, since it only applies to the 1/4". An easy way to test what happens would be to record your stereo and change the HiZ setting and then look at the resulting wav. If your right channel changes at the point you changed the setting, then you have your answer.