Behringer Modamp Module 1005
At 16 HP and under 500 grams, it fits in a Eurorack case without taking much room.
Overview
The Behringer Modamp Module 1005 is a Eurorack module built as a reproduction of the original “System 2500” circuitry from the 1970s. It is sold as both a ring modulator and a voltage-controlled amplifier (VCA). It fits standard Eurorack cases. It is small and draws little current, and it is built around a discrete balanced modulator circuit, like its analog predecessor.
The Module 1005 has nine patch points. It runs on standard Eurorack power rails and draws 60 mA from the +12 V supply and 45 mA from the -12 V rail, with no load on the +5 V line. The operating temperature range is 5° C to 40° C (41° F to 104° F). Input impedance is rated at 50 kΩ (unbalanced), with a maximum input level of +12 V and a minimum switching threshold of +4 V.
There is one quirk. A forum report says "the carrier’s audio comes through no matter what," which points to limited carrier suppression during ring modulation. It may be intentional, a result of copying the original circuit faithfully, or an artifact of component tolerances in the reproduction. Some users may welcome the bleed. Others will expect the complete carrier nulling of an ideal ring modulator.
Specifications
| Manufacturer | Behringer |
| Model | Modamp Module 1005 |
| Type | Eurorack Module |
| Width | 16 HP |
| Depth | 43 mm |
| Current consumption | 60 mA (+12 V) / 45 mA (-12 V) |
| Standard operating temperature | 5° C to 40° C (41° F to 104° F) |
| Inputs | 2 Signal inputs with level control |
| Input Impedance | 50 kΩ, unbalanced |
| Max input level | +12 V |
| Minimum switching threshold | +4 V |
| CV in | 1 x 3.5 mm TS jack, DC coupled |
| Features | MOD and UNMOD mode for use as ring modulator or VCA |
| Features | Integrated VCA with gain control and switch between linear and exponential control characteristics |
Key Features
Authentic reproduction of the original “System 2500” circuitry from the 70's
Behringer positions the Module 1005 as a re-creation of the analog circuitry in the 1970s-era System 2500. That lineage is aimed at users who want vintage-style ring modulation without hunting down rare or expensive original hardware. The balanced modulator stage uses discrete components, which suggests an effort to preserve the sound of that era. No detailed documentation confirms component-level accuracy or layout fidelity.
MOD and UNMOD mode for use as ring modulator or VCA
The module has two jobs. In MOD mode it performs ring modulation, multiplying two audio signals to produce sum and difference frequencies. The results are metallic, bell-like, or inharmonic. Switching to UNMOD mode turns the circuit into a VCA, and the "UNMOD gain control" sets output level by hand.
Integrated VCA with gain control and switch between linear and exponential control characteristics
The VCA section has a toggle to select between linear and exponential response curves. Exponential is typically preferred for pitch-like response in audio-level amplitude shaping. Linear suits precise, proportional control, such as envelope following or modulation depth scaling. The switch lets users match the response to the patch without needing an external VCA.
Collectibility & Value
New units sell at retail prices around $37 (Thomann), £33 (Gearnews), or CHF 66.60 (MusiX). No secondary market data or collector premiums are documented. The reported carrier bleed may affect performance expectations, but no widespread failure patterns or maintenance concerns have been recorded.
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