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Last Modified: January 20, 2008
 
 
Rack Mounted Products
JMP-6 Six Channel Mic Preamp
SMP-2 Discrete JFET Mic Preamp New
FetCode Tube Mic Preamp
CS-1 Channel Strip
NSEQ-F Upgrade PCB
 
Class A Discrete JFET Modules
JFET-992 Discrete Opamp
JFET-993 Discrete Opamp
DLR-1 Differential Line Receiver
JMP-1 Transformerless Mic Preamp
Unity Gain Buffer Module
 
Custom
Sony 3036 Retrofit Modules
 
1-24 pieces $39.95 ea 25-50 pieces $36.95 ea 50 pieces $32.95 ea
 

The DLR-1 is 1” x 1” potted module with a pin-out and footprint that is compatible with currently produced discrete operational amplifiers such as the API 2520™ , Hardy/Jensen 990™ , and others. The DLR-1 differs from these other amplifiers in that it is an all JFET Class A amplifier and is primarily designed as an input receiver. However the design of the DLR-1 allows it to be used in other applications as well, such as a standard operational amplifier in applications where driving low load impedances (< 3K ohms) in not a requirement, but where highest sonic performance is required.

As mentioned the DLR-1 is primarily designed for input amplifier applications. Such amplifiers are usually operated at unity gain. The DLR-1 has minimal open loop gain and thus has low negative feedback applied when it is operated at unity gain, compared to most other operational amplifiers. Further, the DLR-1 is an extremely linear design and offer high performance with little or no feedback: something most other opamps can not accomplish.

The DLR-1 uses extremely low noise, tight-matched, complementary JFET devices for its input stage. The remaining devices are also low noise JFETs from the same family of devices. The output stage of the DLR-1 uses a common-source configuration instead of the more common common-drain (or emitter-follower) configuration. While this does result in a higher open-loop output impedance, in practical applications, this is not a problem.