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Jensen Transformers SUB-2XX

ISO-MAX Stereo Balanced Audio Input Isolator

Made in the USA
Jensen Transformers SUB-2XX ISO-MAX Stereo Audio Input Isolator

Jensen Transformers SUB-2XX ISO-MAX Stereo Audio Input Isolator

Jensen Transformers SUB-2XX Stereo 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-2XX 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-2XX 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.  The SUB-2XX is housed is a sturdy NEMA metal enclosure, measuring 7.0" W x 3.5" D x 1.6" H., including the flanges.  The flanges have mounting holes, which are handy for permanent installations.

FYI: For best results, the cables on the input side of the SUB-2XX 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, XLR/TRS, XLR/RCA, TRS/TRS, RCA/RCA, RCA/XLR-M configurations are also available for a small additional charge.  You may also choose the "None" option if you prefer to use the back-panel barrier strip for either (or both) of the connections.  The 10 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-2XX with similar (but inferior) products.  Jensen Transformers' ISO-MAX Audiophile-Quality stereo 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-2XX 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-2XX 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-2XX into your signal path, and you may want to consider upgrading your existing cable(s) as well. The SUB-2XX 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-2XX Two channel sub-woofer isolator

The Iso•Max SUB-2XX is a two channel low-frequency isolator created specifically for sub-woofers to eliminate hum and buzz caused by ground loops in balanced audio systems.

  • 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 a rugged flanged enclosure that comes standard with gold plated XLRs and a removable screw-down barrier strip for easy installation in a NEMA enclosure. Plug and play easy to use, this passive interface does not require any power to work. Inside are two specially designed Jensen audio transformers with extended subsonic response to deliver powerful and articulated bass for maximum impact. Even when being subjected to extremes, the SUB-2XX is able to gracefully handle low frequencies down to 20 Hz with less than 0.01% distortion and less than 1 dB of phase shift. To further optimize the performance, a bottom mounted 8 position ‘set & forget’ dip switch enables the user to configure the SUB-2XX grounding scheme as needed. And with better than 100 dB of common mode noise rejection, you can enjoy the full performance of your audio system without noise.

Simply connect the SUB-2XX between the source and the input destination to eliminate ground loops, electromagnetic interference (EMI) and RFI problems. The SUB-2XX will quietly go to work without introducing distortion, phase shift or artifact of any kind. These combined features make the Iso•Max SUB-2XX ideal for balanced home theater systems, professional studios, PA systems and the most demanding post production facilities.

Data Sheet (PDF)

Jensen Transformers SUB-2XX Stereo Audio Input Isolator - Open

TThis picture offers a peek inside, as well as the layout of the back panel.  Please notice that the internals may not be identical to the model pictured, although the back panels are the same.

Jensen Transformers SUB-2XX Connection Example for Live Sound

 Subwoofers have become an essential part of most touring PA systems.  In this example, the SUB-2XX is being used to isolate the subwoofer amplifier racks from the rest of the audio system.

Jensen Transformers SUB-2XX Studio Connection Example

In this studio connection example, the SUB-2XX is connected between the balanced output of a playback system and the balanced stereo inputs on a powered subwoofer.  The signal is faithfully delivered, without smearing or choking, and of course the inherent isolation ensures that there will be no ground loops.

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

Here is the datasheet, in PDF format.

Jensen Transformers 2XX Connector Options

The SUB-2XX comes standard with XLR inputs and outputs (as shown elsewhere on this page), but all of the connector options shown above are also available by special order.  Click the image above to get a closer look at all 10 configuration options.

In-Stock Configurations and Pricing
(see also the special-order configurations below)
Product Description SKU MSRP Your Price Quantity
ISO-MAX Stereo Balanced Audio Line Input Isolator
XLR-female inputs / XLR-male outputs
(This is the default configuration, as shown above)
SUB-2XX $428.99 $389.99
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Special Order Configurations and Pricing
ISO-MAX Product Description SKU MSRP Your Price Quantity
ISO-MAX Stereo Balanced Audio Line Input Isolator
XLR-female inputs / BNC outputs
SUB-2XB $428.99 $389.99
ISO-MAX Stereo Balanced Audio Line Input Isolator
XLR-female inputs / Wire Lead (No front connector) outputs
SUB-2XN $428.99 $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
XLR-female inputs / 1/4" TRS phone outputs
SUB-2XP $428.99  $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
XLR-female inputs / RCA outputs
SUB-2XR $428.99  $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
1/4" TRS phone inputs / 1/4" TRS phone outputs
SUB-2PP $428.99  $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
Wire Lead (No front connector) inputs /
Wire Lead (No front connector) outputs
SUB-2NN $428.99  $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
RCA inputs / Wire Lead (No front connector) outputs
SUB-2RN $428.99  $389.99 
ISO-MAX Stereo Balanced Audio Line Input Isolator
RCA inputs / XLR-male outputs
SUB-2RX $428.99  $389.99 
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