A-B-Y Switching

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Gibsonman63
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A-B-Y Switching

Post by Gibsonman63 »

Recomendations? I was experimenting a while back with two amps and discovered my Whirlwind A-B-Y was taking something away. Now I am considering a hot channel mod for the normal channel of my Super Reverb and would like to switch externally to keep the cosmetics intact. Also for gigging, it would be nice to switch to my Vibrolux Reverb for Fender Clean sounds.

I guess the technical hurdle would be true bypass with pop suppression. I suspect the "Y" or "both" selection is giving me grief. Whatever they are using for isolation is throwing a blanket on my sound. A-B with no coloration would be more useful than A-B-Y with the blanket.
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NickC
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Re: A-B-Y Switching

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Ken Moon
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Re: A-B-Y Switching

Post by Ken Moon »

+1 on the Lehle.

I've tried 5 or 6 A/B/Y boxes over the years (had a Morley A/B/Y for about 15 years), and this is the only one I've used that doesn't cause hum or loss of treble, no matter what the venue power is like, or with external noise sources like stage lights and cell phones.

Some say the others "suck tone", but I've found that means a roll-off in the high end sparkle of the amps. Some brands work OK if you stick to battery power, but hum when you plug them in.

You should be able to get one for $229 with free shipping at a variety of online shops - it's expensive, but that's what you pay if you want to A/B/Y successfully in a variety of venues.
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donzoid
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Re: A-B-Y Switching

Post by donzoid »

If you aren't running one now, you could also try a basic buffer pedal in front of the ABY. That would stop a lot of the tone suck from all the splitting and cable. The Lehle probably has that built into it. I built a buffer for about 30 bucks. Super simple.
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Structo
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Re: A-B-Y Switching

Post by Structo »

Tom

Don't let that smoke out!
Gibsonman63
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Re: A-B-Y Switching

Post by Gibsonman63 »

Wow, much cheaper than the Lehle. Does anyone have experience with this one?
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rogb
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Re: A-B-Y Switching

Post by rogb »

https://tubeamparchive.com/viewtopic.ph ... sc&start=0

I use this one - BigShot ABY. Works great but there is a little A/B bleed noticeable at full volume, but otherwise at small gig volumes, no problems.

If I had the cash, then prolly go for the Lehle or Twin City (active and LEDs) TBH, spent all mine on a Suhr MiniMix 2, which was essential :D
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M Fowler
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Re: A-B-Y Switching

Post by M Fowler »

I use the BigShot ABY and have had no problems but then I admit I'm not a pro user only small time gigger. :)

From reports I think the Lehle is the way to go.
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Ken Moon
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Re: A-B-Y Switching

Post by Ken Moon »

Gibsonman, it's hard to be sure about these boxes until you try them in the actual places where you'll be playing, because hum and grounding problems depend so much on the house wiring, and on other equipment plugged into the same circuits, like PA amps and lights. I even tried using an "on-line" computer UPS once, but it didn't help. Don't use those 3-prong to 2-prong plugs, you might get a nasty shock :shock:

If you have an especially friendly guitar store near you, you could talk to them about their return policy, and take a chance on the BigShot at $79 if they'll take it back if it doesn't work for you.

I think the difference in cost between these two units (and between these and high end balanced studio power conditioners that cost $2k-$4k) is the brand and model of the isolation transformers used. It also looks like the Lehle uses 2 isolation transformers and the Bigshot uses one.

I probably just confused you more than anything, but that's my guess on the cost differential between the units. I wish I could definitively say whether or not the Bigshot will work for you, but you really can't know until you try it :(
Gibsonman63
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A little research

Post by Gibsonman63 »

For those interested:

From the Radial Bigshot ABY manual:
"Will the transformer change the tone of the second output?
Yes. You will hear a slight tonal difference as the signal passes through the transformer. Because the BigShot ABY is a passive device, it does not employ buffering to counteract the phenomenon. However, you can easily make up the tonal difference using the tone controls on
the amplifi er. The tonal shift of the transformer can be minimized by placing a buffer in front of the BigShot ABY such as another effect pedal equipped with a buffered output."

Attached is a simplified schematic of the Lehle little dual. Seems to be the same concept, more or less. I guess it gets down to the transformers used and build quality. Thanks for the input, guys.
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overtone
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Re: A-B-Y Switching

Post by overtone »

That surprised me because I took it for granted that the Lehle must be using a buffer.

No one has mentioned R.G. Keen's ABY splitter yet. His design uses a buffer to drive the transformer. There are quite a few options for a 1:1 transformer for 10k impedance to suit any budget and need. It is on my to-do list.
Here is the link to his website pdf in case you want to roll your own:
http://www.geofex.com/FX_images/TransformerSplitter.pdf

tony
Last edited by overtone on Fri Mar 28, 2014 11:02 pm, edited 1 time in total.
wyatt
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Re: A-B-Y Switching

Post by wyatt »

overtone wrote:That surprised me because I took it for granted that the Lehle must be using a buffer.
I think it's because it's design to run either way..guitar to two amps...or dual pickup systems to one amp.
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