Phone 800-517-8431

Keithley 2015

6 1/2-digit Total Harmonic Distortion Multimeter with GPIB and RS-232 Interfaces

Brand: Keithley
Model No: 2015
Our Model No: 2015
Condition: NEW
PDF Document Icon Data Sheet (400 KB)


Product Features:

  • 6 1/2-digit resolution
  • THD, THD+Noise, and SINAD measurements
  • 20Hz-20kHz sine wave generator
  • Fast frequency sweeps
  • 4Vrms single-ended or 8Vrms differential output
  • Individual harmonic magnitude measurements
  • 5 standard audio shaping filters
  • 13 DMM functions
  • GPIB and RS-232 interfaces


  • Wireless communication device audio quality testing
  • Component linearity testing
  • Lighting and ballast THD limit conformance testing
  • Telephone and automotive speaker testing

The Keithley 2015 6 1/2-Digit Total Harmonic Distortion Digital Multimeter combines audio band quality measurements and analysis with a full-function 6 1/2-digit DMM. Test engineers can make a broad range of voltage, resistance, current, frequency, and distortion measurements, all with the same compact, half-rack measurement instrument. The 2015 offers additional processing capacity for frequency spectrum analysis.

Frequency Domain Distortion Analysis

For applications such as assessing non-linear distortion in components, devices, and systems, DSP-based processing allows the Models 2015 to provide frequency domain analysis in conventional time domain instruments. It can measure Total Harmonic Distortion (THD) over the complete 20Hz to 20kHz audio band. It also measures over a wide input range (up to 750Vrms) and have low residual distortion (-87dB). The THD reading can be expressed either in decibels or as a percentage.

In addition to THD, the 2015 can compute THD+Noise and Signal-to-Noise plus Distortion (SINAD). For analyses in which the individual harmonics are the criteria of greatest interest, the instruments can report any of the (up to 64) harmonic magnitudes that can be included in the distortion measurements. The user can program the actual number of harmonics to be included in a computation, so accuracy, speed, and complexity can be optimized for a specific application.

Figure 1 shows a plot of a square wave’s harmonics (frequency components) computed and transmitted to a personal computer by the Model 2015 or 2016. A square wave’s spectral content consists of only odd harmonics whose magnitudes are (1/harmonic number × the magnitude of the fundamental).Click for larger image

Figure 1. Frequency Spectrum of 1kHz Square Wave

Figure 2 shows a sample test system schematic with a telecommunication device in a loop back mode test. The Audio Analyzing DMM’s source provides a stimulus frequency sweep, and the Audio Analyzing DMM measures the response from the microphone circuit.Click for larger image

Figure 2. THD Analysis and Frequency Response of Portable Wireless Telecommunication Device

Figure 3 shows the resulting frequency domain analysis of the THD and the first three harmonics as a function of frequency.Click for larger image

Figure 3. THD and 2nd, 3rd, and 4th Harmonics as a Function of Frequency

Optimized for Production Testing

The Model 2015 can perform fast frequency sweeps for characterizing audio-band circuitry in production test systems. For example, the instruments can execute a single sweep of 30 frequencies and transmit both RMS voltage readings and THD readings to a computer in only 1.1 seconds. With that data, a complete frequency response analysis and a harmonic distortion vs. frequency analysis can be performed in a very short time. Thus high speed testing of the audio performance of a high volume device such as a cellular telephone can be performed without reducing the number of tests or reducing the measurements in each test. With this instrument, which is optimized for production testing, test engineers can lower test times, in comparison to test speeds achievable with general purpose audio analyzers, without sacrificing production test quality.

Dual Output Source

The 2015 includes an internal audio band sine wave source for generating stimulus signals. A second output, the inverse of the first output, is also available, simplifying the testing of differential input circuits for common mode or noise cancellation performance.

Figure 4 shows the time domain analysis of microphone circuit output voltage as a function of frequency.Click for larger image

Figure 4. F requency Response

Figure 5c. CCIR Weighting FilterClick for larger image

Figure 5c. CCIR Weighting Filter

Figure 6. The Model 2015-P and 2016-P directly identify peak values of the frequency spectrum.Click for larger image

Figure 6. Frequency Spectrum

Wide Selection of Audio Filters

Five industry-standard bandpass filters are provided for shaping the input signal for audio and telecommunication applications. Available filters include the CCITT weighting filter, CCIR filter, C-message filter, CCIR/ARM filter, and "A" weighting filter. The 2015 provides programmable, high cutoff (low pass) and low cutoff (high pass) filters. Furthermore, the two filters can be implemented together to form a bandpass filter. The programmable filters can be used to filter out noise generated by electromechanical machinery on the production floor or to simulate other types of system transmission characteristics.

Broad Measurement Flexibility

In addition to their THD, THD+Noise, SINAD, and individual harmonic measurement capabilities, the instruments provide a comprehensive set of DMM functions, including DCV, ACV, DCI, ACI, 2WW, 4WW, temperature, frequency, period, dB, dBm, and continuity measurements, as well as diode testing. This multi-functional design minimizes added equipment costs when configuring test setups.

Wide Band or Narrow Band Noise Measurements

The 2015 is capable of measuring both wide band noise and narrow band noise. Alternatively, its DSP (Digital Signal Processing) capabilities allow users to make frequency domain measurements of RMS voltage noise over the 20Hz - 20kHz frequency audio band, or a narrow portion of the band. Furthermore, noise measurements can be extracted in the presence of a stimulus signal for fast signal-to-noise computations.

  • 1 - 6 1/2-Digit THD/Audio Analysis Multimeter w/Line Cord
  • 1 - Safety Test Leads (1751)
  • 1 - Certificate of Calibration
  • 1 - User Manual/CD
Model Description Buy Now Price
8501-2 Keithley 8501-2 2m Micro-DIN-Male-to-Micro-DIN-Male Trigger Link Cable Add to Cart


8503. Keithley 8503. 1m DIN Male-to-BNC Male Trigger Link Cable Add to Cart


4288-1 Keithley 4288-1 Single Fixed Rack Mount Kit Add to Cart


4288-2 Keithley 4288-2 Dual Fixed Rack Mount Kit for Models 2000, 2700, and 6487 Add to Cart


KPCI-488LPA Keithley KPCI-488LPA IEEE-488.2 Interface Module for PCI Buses Add to Cart


KUSB-488B Keithley KUSB-488B IEEE-488.2 USB-to-GPIB Interface Adapter for USB Ports Add to Cart


Model Description Buy Now Price
C/2015-3Y-17025 Keithley C/2015-3Y-17025 3-Year ISO 17025 Calibration Contract for Model 2015 Add to Cart


C/2015-3Y-DATA Keithley C/2015-3Y-DATA 3-Year Calibration Contract with Data Plan for Model 2015 Add to Cart


C/2015-3Y-STD Keithley C/2015-3Y-STD 3-Year STD Calibration Contract for Model 2015 Add to Cart


C/2015-5Y-17025 Keithley C/2015-5Y-17025 5-Year ISO 17025 Calibration Contract for Model 2015 Add to Cart


C/2015-5Y-DATA Keithley C/2015-5Y-DATA 5-Year Calibration Contract with Data Plan for Model 2015 Add to Cart


C/2015-5Y-STD Keithley C/2015-5Y-STD 5-Year STD Calibration Contract for Model 2015 Add to Cart


Gold Plans
Model Description Buy Now Price
2015-3Y-EW Keithley 2015-3Y-EW 3-Year Factory Warranty Extension for Model 2015 Add to Cart


2015-5YR-EW Keithley 2015-5YR-EW 5-Year Factory Warranty Extension for Model 2015 Add to Cart


2015-EW Keithley 2015-EW 1-Year Factory Warranty for Model 2015 Add to Cart


Datasheet: PDF Document Icon(400 KB)
Manual: PDF Document Icon(2.37 MB)
↑ Back to Top