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Jensen Transformers SUB-XX

ISO-MAX Single-Channel mono Balanced / XLR Audio Input Isolator

Made in the USA
Jensen Transformers SUB-XX ISO-MAX Single-Channel mono Audio Input Isolator

Jensen Transformers SUB-XX ISO-MAX Single-Channel mono Audio Input Isolator

Jensen Transformers SUB-XX Single-Channel mono Balanced Audio Input Isolator typically offers common mode rejection of 105 dB 90 dB common mode isolation at 60 Hz while also helping to eliminate RF interference from sources like television and radio stations.

The SUB-XX features extended low frequency response, right down to 1 Hz.  Being a passive device, it requires no power supply, and thus cannot itself add any any noise to the connected audio system.  Distortion at 20 Hz is ultra-low at less than 0.01 percent.  The SUB-XX can eliminate noise inference, such as 60 cycle hum, and also  higher frequency noises, such as buzzes, clicks and pops from motors, light dimmers, and RF.

Both the sources and loads may be either balanced or unbalanced for maximum interconnection flexibility.  For superior strength, the SUB-XX is housed in a sturdy 1/8" thick extruded aluminum enclosure, 3" wide x 3" deep x 2" high.

FYI: For best results, the cables on the input side of the SUB-XX should be under 200 meters (600 feet) in length.  The output cables should be no longer than 1 meter (3.3 feet).

The XLR to XLR configuration shown here is the standard connector configuration, but XLR/BNC, RCA/RCA, 1/4" TRS/XLR, 1/4" TRS/1/4" TRS and XLR/1/4" TRS configurations are also available for a small additional charge.  The six different options are show at the lower-right.

If you're not sure that this is the best model for your application, please check out our Jensen Transformers Application Guide.

Please do not confuse the SUB-XX with similar (but inferior) products.  Jensen Transformers' ISO-MAX Audiophile-Quality Single-Channel mono audio isolators provide the ultimate signal interface solutions.  They solve the fundamental problems associated with ground loops, without degrading signal quality.

With inferior products coming from all over the world, we think it is a genuine treasure to find a company like Jensen Transformers, actually designing and manufacturing some of the finest products in the world, right here in the USA, and we are proud to be able to offer their products. The SUB-XX is made in the USA, is backed by the manufacturer's comprehensive one-year warranty, and has a remarkable 20-year warranty on the transformer device itself.

Ground Loops?

(or why the best planned systems sometimes sound bad)

It is a subject that is seldom discussed in manufacturers publications, or even in magazines of the trade, but ground loops can happen in even the best-planned audio systems.

When devices in the same system are powered by separate power sources, that almost always causes a difference in ground potential between the two pieces of equipment. It can be because one run is longer than the other. or because one of the circuits is loaded more heavily than the other, or any number of other reasons that are beyond the scope of this article, but the result of this difference in ground potential is commonly referred to as a ground loop.

The Solution

Elegant in its simplicity, the Jensen Transformers SUB-XX is simply inserted into the signal path, immediately resulting in the effects of the ground loop becoming a non-issue. Problem solved. There are not too many things that can provide so much improvement in an audio system with so little effort.

Don't Forget the Cables!

Good cables are very important in the fight against hum and noise. You will need at least one short patch cable in order to insert the SUB-XX into your signal path, and you may want to consider upgrading your existing cable(s) as well. The SUB-XX does not include any cables, but if you need them, we have some very high-performance XLR cables available. Please click here to see them!

Jensen Transformers' Description

SUB-XX Single Channel Isolator

Single channel isolator with extended low frequency response for pro audio subwoofers with balanced XLR inputs.

  • Eliminates hum and buzz caused by ground loops
  • Extended low frequency response down to 0.1 Hz
  • Less than 0.01% distortion at 20 Hz
  • Plug and play easy to use, no power required

The design begins with an extruded aluminum case that comes standard with gold plated XLR connectors. Plug and play easy to use, this passive interface does not require any power to work. Inside is a high performance Jensen transformer that is able to withstand signal levels to +18 dBu at 20 Hz without discernible distortion. This provides galvanic isolation between the input and output to eliminate hum and buzz caused by ground loops, while rejecting 60 Hz noise by as much as 105 dB.

Simply connect the SUB-XX between the source and the input destination to eliminate ground loops, electromagnetic interference (EMI) and RFI problems. The SUB-XX will quietly go to work without introducing distortion, phase shift or artifact of any kind. These combined features make the Iso•Max SUB-XX ideal for balanced home theater systems, professional studios, PA systems and the most demanding post production facilities.

Data Sheet (PDF)

Jensen Transformers SUB-XX Sinngle Channel Mono Subwoofer Audio Input Isolator, back

Here is a look at the back of the isolator.

Jensen Transformers SUB-XX PA Connection Example

In this example, the SUB-XX is being used to isolate the subwoofer amplifier racks from the rest of the audio system.

Jensen Transformers SUB-XX Studio Connection Example

Here the SUB-XX is being used to isolate the inputs of a powered subwoofer. In a studio setup like this, the ISO-MAX delivers the audio from the playback system to the sub's inputs without any choking or smearing, while also eliminating hum-inducing ground loops.

Jensen Transformers XX Connector Options

The SUB-XX comes as shows with XLR inputs and outputs, but all of the connector options shown above are also available by special order.  Click for a closer look at the six available configuration options.

Jensen Transformers SUB-2XX Datasheet - click to download PDF

Here is the datasheet for the electrically identical SUB-2XX model. PDF format.

Configurations and Pricing
Product Description SKU MSRP Your Price Quantity
ISO-MAX Single-Channel Mono Balanced Audio Line Input Isolator
(1) XLR-female input / (1) XLR-male output
(as shown on this page)
SUB-XX $252.99 $229.99
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Special Order Configurations and Pricing
ISO-MAX Product Description SKU MSRP Your Price Quantity
ISO-MAX Single-Channel mono Balanced Audio Line Input Isolator
(1) RCA input / (1) XLR-male output
(not shown, special order item)
SUB-RX $252.99 $239.99
ISO-MAX Single-Channel mono Balanced Audio Line Input Isolator
(1) XLR-female input / (1) RCA output
(not shown)
SUB-XR $252.99 $239.99
ISO-MAX Single-Channel mono Balanced Audio Line Input Isolator
(1) XLR-female input / (1) 1/4" TRS phone output
(not shown, special order item)
SUB-XP $2582.99 $239.99
ISO-MAX Single-Channel mono Balanced Audio Line Input Isolator
(1) 1/4" TRS phone input / (1) 1/4" TRS phone output
(not shown, special order item)
SUB-PP $252.99 $239.99
ISO-MAX Single-Channel mono Balanced Audio Line Input Isolator
(1) XLR-female input / (1) BNC output
(not shown, special order item)
SUB-XB $252.99 $239.99
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