Ampeg System Selector

[AURORA4DTH]

I am looking Looking for an Ampeg System Selector. i have MANY heads I need to connect at one time. This seems to be the only reasonable option. Kepp in mind they are Guitar Tube heads.


The selector has two inputs for tube head. All other 6 are not.
I only ever use one head at a time in the studio so my amps dont have to see a load all the time. Can i use that ampeg switcher all 8 inputs with tube heads if i am only using one cab at a time. No other heads turned on other than the one I am using. Also i always use the same cab so whatever head that i would be using would automatically be hooked up to the cab.

For example.

All 8 inputs on the selector would be used from the tube amp heads but only one output would be used on the selector. So the cab selector just stays in position one while i switch between heads, never leaving any head in on mode if it are not being used. So will i run any risk in damaging my tube heads using it this way?

As long as one of the non tube inputs has a load on the other end when I turn the head on and select it i am thinking it should be fine.

Thoughts??

[JimmyM]

As long as you don't pass any signal through the unused heads while not being used, you should be OK. Good luck finding one, though...haven't seen them for years. You could always make one or have one made, though.

[AURORA4DTH]

Jimmy
thanx. that is what i thought as well. As long as they are not on and ready to go it should be ok.
When I am ready to use a specific head that is not on one of the "Tube" inputs as long as I have the cab selected and head selected so that the load is in line should be ok.

I just didnt know if there was any thing else weird in those paths that could damage a tube head.

Thanx for the reply.

[Jim C]

I don't think this is true.
I've had one for 10 years but have never opened the cover.
I believe there are components for the 2 dedicated tube channels to protect output transformers.
Hopefully Mr.Tiers will chime in.
I saw one on eBay about 3 months ago; they go for between $50 - 150 used and worth every penny for A/B comparison testing.

[AURORA4DTH]

arent the output transformers in trouble if no load is present? Because like i said when I use any particular head with cab they will both be selected before turning on, so in essence the load will be there. let m know if i am way off here.

[LoTone]

Radial Engineering has a series of splitters boxes. That might solve your problem.

http://www.radialeng.com/r2011/splitter-products.php

Good luck.

[Jerrold Tiers]

There are a couple inputs with loads on them to keep a tube amp stable. The others don't have them.

The purpose is to keep the output loaded..... if a tube amp with negative feedback around the transformer has no load, the phase shift through the transformer is changed and may turn negative (stabilizing) feedback into positive feedback (makes an oscillator) that can endanger the output tubes and cause other problems.

Short story..... you generally need the loads even if no signal is going through the amp.

[JimmyM]

Then never mind my first reply

[AURORA4DTH]

Lotone, I was on the phone with radial for twenty min. The guy even checked with the dudes who build the boxes, they have nothing that will work for me.

[AURORA4DTH]

jeorold, you say "if a tube amp with negative feedback around the transformer has no load"

What if they amp is only turned on when it is being used and the cab on the other end is connected to that head through the selector. in essence the load is always on it right?

I dont leave me heads on when i am not using them. The one being used will always be connected to a cab when it is on.

all others will be off.

[jungleheat]

Then what do you need a switcher for? If you're switching heads on and off, you might as well take a few seconds to swap a speaker cable too. What problem are you trying to solve exactly?

[AURORA4DTH]

Jungle, basically all the heads are in a control room and the are cosmetically shelved in for looks. Nice and flush, very clean. I recently re did my set up and i have no access to the back panels very easily, however I still need to be able to turn them on when i am ready and go, or just whatever one i want to use. Right now I have 6 speaker cables coming out from behind the head casing and I have a coupler tied to my panel in the tracking room. I have to hot swap the cables right now. As we are getting more coverage in magazines etc i need everything to be perfect and cosmetically clean. So you see just one amp at a time but turning a dial would be awesome rather than hot swapping cables.

[Jerrold Tiers]

Originally Posted by AURORA4DTH

jeorold, you say "if a tube amp with negative feedback around the transformer has no load"

What if they amp is only turned on when it is being used and the cab on the other end is connected to that head through the selector. in essence the load is always on it right?

I dont leave me heads on when i am not using them. The one being used will always be connected to a cab when it is on.

all others will be off.

The system selector was designed to allow quickly changing amps and speakers for comparisons..... in those cases you need to have the amp on.

If you just want to be able to connect several amps and several speakers in any combination wanted, and NOT have the quick comparison feature, then you are as well off to put a number of connectors on a panel and simply use a "patch cord" to connect any combination wanted at the moment.

That may be what you have now, I'm not clear from the description.

It is much easier to obtain, easier to repair, and unlikely to have any problems in the first place. It is immediately obvious what connection is made, and far less likely to lead to mistakes. If nicely done, it can be somewhere between "retro" and slick.

Your choice what connectors you use..... almost any will make a better contact than the selector switches.

If you only turn on the amp when a speaker is connected, that's the same as "normal" use of the amp, and obviously won't be an issue.

[AURORA4DTH]

Jerrold,
Thanx a ton for the advice. i think i may try and find the selector for now and in the long run build me a panel as you suggested. i just wanted to be sure on the non tube inputs before trying to track one down.

I have a panel with two speaker outputs on it in my tracking room now that run from the control. in the long run i just want to take that panel off and hard wire 5 more to the panel.
That is a pain biut I know I need to do it. Maybe it will be easier than trying to find this selector haha.