Back to the main page Back to category Preamps and Channel Strips
musical instrument details
Demeter HM-1 2-Channel H-Series Tube Mic Preamp valve pre amp DI d.i.
Estimated price for orientation: 620 $
Category: Preamps and Channel Strips
Class:
Description Condition: Used: An item that has been used previously. The item may have some signs of cosmetic wear, but is fully operational and functions as intended. This item may be a floor model or store return that has been used. See the seller’s listing for full details and description of any imperfections. See all condition definitions- opens in a new window or tab ... Read moreabout the condition UPC: Does not apply
Great sounding tube pre amp / D.I.Works great. Sounds great. Shows cosmetic / rack wear.Great, in depth review available at From eMusician —"The HM-1's sturdy steel and aluminum chassis is ventilated on its top and bottom plates and gets only slightly warm when cooking up your signals. Rear-panel I/O consists of balanced XLR and ¼-inch TRS jacks for each channel (see Fig. 2), wired in parallel so you can use any combination of jacks for input and output. The TRS jacks are not cross-coupled, so you can patch unbalanced gear safely to the HM-1's I/O with standard guitar cords. As with other equipment that uses this ubiquitous plug-and-play I/O topology, 6 dB of signal level is lost at each jack that you use in Unbalanced mode. The rear panel also provides a standard IEC connector with a detachable three-prong AC cord.Each channel also provides an unbalanced ¼-inch DI jack on the front panel for direct-instrument input. The DI inputs access the HM-1's circuitry after the input transformer but before the tube gain stage. Both front and rear input jacks can accept mic or line-level signals.Each HM-1 channel sports the same generous allotment of front-panel controls. Four buttons access, from left to right, a low-cut filter, 20 dB mic pad, 48V phantom power (with associated status LED), and polarity inverse. The Low-Cut switch rolls off lows below 200 Hz with a gentle 6 dB-per-octave slope, resulting in a 12 dB cut at 40 Hz.The 20 dB mic pad is placed in the circuit before the input transformer, so it doesn't work for DI inputs (which enter the box after the transformer). Musical instruments put out relatively weak signals, however, so you usually don't need to pad them. Giving DI inputs a transformerless entry into the HM-1 better preserves an instrument's original tonal balance. Demeter's design makes good sense.Each channel also has a continuously variable rotary gain control that provides as much as 30 dB of additional tube-amplification gain. The minimum and maximum values vary depending on which input (mic or DI) you are using and whether the pad is switched in for mic input. With the Gain knob set at hard left (fully counterclockwise), a DI input will receive 12 dB of gain; with the knob turned hard right, the 30 dB boost results in a total 42 dB of added gain for a DI input. That should be enough to attain close to a 0 dBFS level on most digital recorders with balanced inputs.A hard-left Gain-knob setting will provide 30 dB of gain for mic input signals (with the pad switched out); switch in the pad, and the level drops to 10 dB of gain. Setting the Gain knob hard right gives you 30 dB more gain. You get 60 dB total with the pad switched out and 40 dB total with the pad switched in. The HM-1's maximum gain of 60 dB should be adequate for recording with most condenser and dynamic mics. The unit can handle a hefty +29 dBm maximum output level in Balanced mode, which is more than sufficient for most professional applications.A front-panel overload LED lights up to warn you that the signal level is within 6 dB of overloading the tube-amplification circuit. If you have the gain control set to minimum for a microphone signal and the overload light is still on, switching in the mic pad should drop the level enough to preclude distortion.Each channel also provides a continuously variable rotary Volume knob, which you can use to smoothly fade your output level from unity down to silence. Because the attenuator occurs after the tube amp, however, it will do nothing to prevent overload caused by blazing levels occurring before the tube amplifier. That's the microphone pad's job.Each channel contains a tricolor, ten-segment LED output meter — an upscale feature that is not found on most cost-effective microphone preamps. The LED is referenced to a +3 or -8 dBm level, depending on the setting of the reference-level switch. (Each channel has its own switch.) Three red LEDs show levels above the 0 mark, but the scale of the meters is arbitrary. With one of the meters referenced to +3 dBm, I fed roughly -9 dBFS input to the A/D on my Yamaha 02R's channel insert to light all three of the HM1's red LEDs. Plenty of headroom was still available (both on the HM-1 and the 02R) beyond the top of the meter's range, but the meter was useless for gauging hotter levels. I would prefer the HM-1's meters to be calibrated so that the top LED is referenced to the mic preamp's maximum output level or to some digital standard such as +19, +22, or +24 dBm. As they stand now, the meters should work well with systems calibrated to -10 dBV nominal operating levels.”Shipping price listed is for shipping to a street address in the contiguous USA and includes shipping, packing materials, & insurance, as well as signature confirmation for purchases requiring it.Please contact me within 24 hours of receiving the item if there are any problems with it or the package. Please save the box and packing materials for insurance purposes.Available for free pick-up in Los Angeles, CA if paid in cash at time of pickup as Paypal no longer considers pickup a valid shipping method.Yes -- I try to combine shipping for multiple items purchased at the same time. Please message me about specific auctions.
Description
| Condition: | Used: An item that has been used previously. The item may have some signs of cosmetic wear, but is fully operational and functions as intended. This item may be a floor model or store return that has been used. See the seller’s listing for full details and description of any imperfections. See all condition definitions- opens in a new window or tab ... Read moreabout the condition | UPC: | Does not apply |
Great sounding tube pre amp / D.I.Works great. Sounds great. Shows cosmetic / rack wear.Great, in depth review available at From eMusician —"The HM-1's sturdy steel and aluminum chassis is ventilated on its top and bottom plates and gets only slightly warm when cooking up your signals. Rear-panel I/O consists of balanced XLR and ¼-inch TRS jacks for each channel (see Fig. 2), wired in parallel so you can use any combination of jacks for input and output. The TRS jacks are not cross-coupled, so you can patch unbalanced gear safely to the HM-1's I/O with standard guitar cords. As with other equipment that uses this ubiquitous plug-and-play I/O topology, 6 dB of signal level is lost at each jack that you use in Unbalanced mode. The rear panel also provides a standard IEC connector with a detachable three-prong AC cord.Each channel also provides an unbalanced ¼-inch DI jack on the front panel for direct-instrument input. The DI inputs access the HM-1's circuitry after the input transformer but before the tube gain stage. Both front and rear input jacks can accept mic or line-level signals.Each HM-1 channel sports the same generous allotment of front-panel controls. Four buttons access, from left to right, a low-cut filter, 20 dB mic pad, 48V phantom power (with associated status LED), and polarity inverse. The Low-Cut switch rolls off lows below 200 Hz with a gentle 6 dB-per-octave slope, resulting in a 12 dB cut at 40 Hz.The 20 dB mic pad is placed in the circuit before the input transformer, so it doesn't work for DI inputs (which enter the box after the transformer). Musical instruments put out relatively weak signals, however, so you usually don't need to pad them. Giving DI inputs a transformerless entry into the HM-1 better preserves an instrument's original tonal balance. Demeter's design makes good sense.Each channel also has a continuously variable rotary gain control that provides as much as 30 dB of additional tube-amplification gain. The minimum and maximum values vary depending on which input (mic or DI) you are using and whether the pad is switched in for mic input. With the Gain knob set at hard left (fully counterclockwise), a DI input will receive 12 dB of gain; with the knob turned hard right, the 30 dB boost results in a total 42 dB of added gain for a DI input. That should be enough to attain close to a 0 dBFS level on most digital recorders with balanced inputs.A hard-left Gain-knob setting will provide 30 dB of gain for mic input signals (with the pad switched out); switch in the pad, and the level drops to 10 dB of gain. Setting the Gain knob hard right gives you 30 dB more gain. You get 60 dB total with the pad switched out and 40 dB total with the pad switched in. The HM-1's maximum gain of 60 dB should be adequate for recording with most condenser and dynamic mics. The unit can handle a hefty +29 dBm maximum output level in Balanced mode, which is more than sufficient for most professional applications.A front-panel overload LED lights up to warn you that the signal level is within 6 dB of overloading the tube-amplification circuit. If you have the gain control set to minimum for a microphone signal and the overload light is still on, switching in the mic pad should drop the level enough to preclude distortion.Each channel also provides a continuously variable rotary Volume knob, which you can use to smoothly fade your output level from unity down to silence. Because the attenuator occurs after the tube amp, however, it will do nothing to prevent overload caused by blazing levels occurring before the tube amplifier. That's the microphone pad's job.Each channel contains a tricolor, ten-segment LED output meter — an upscale feature that is not found on most cost-effective microphone preamps. The LED is referenced to a +3 or -8 dBm level, depending on the setting of the reference-level switch. (Each channel has its own switch.) Three red LEDs show levels above the 0 mark, but the scale of the meters is arbitrary. With one of the meters referenced to +3 dBm, I fed roughly -9 dBFS input to the A/D on my Yamaha 02R's channel insert to light all three of the HM1's red LEDs. Plenty of headroom was still available (both on the HM-1 and the 02R) beyond the top of the meter's range, but the meter was useless for gauging hotter levels. I would prefer the HM-1's meters to be calibrated so that the top LED is referenced to the mic preamp's maximum output level or to some digital standard such as +19, +22, or +24 dBm. As they stand now, the meters should work well with systems calibrated to -10 dBV nominal operating levels.”Shipping price listed is for shipping to a street address in the contiguous USA and includes shipping, packing materials, & insurance, as well as signature confirmation for purchases requiring it.Please contact me within 24 hours of receiving the item if there are any problems with it or the package. Please save the box and packing materials for insurance purposes.Available for free pick-up in Los Angeles, CA if paid in cash at time of pickup as Paypal no longer considers pickup a valid shipping method.Yes -- I try to combine shipping for multiple items purchased at the same time. Please message me about specific auctions.