Bluetooth Classic
Bluetooth · 7 specs
Direct Answer
Bluetooth Classic encompasses Bluetooth Core Specifications v1.0 through v3.0 + HS. Operating in the 2.4 GHz ISM band across 79 channels with Frequency-Hopping Spread Spectrum (FHSS), it established wireless audio (A2DP), hands-free telephony (HFP), and serial peripheral connectivity (SPP/HID) at data rates up to 3 Mbps.
Source: Bluetooth SIG Core Specification v1.0–v3.0 + HS / IEEE 802.15.1 · Last reviewed Aug 28, 2026
Specs
| Bluetooth Generations | v1.0, v1.1, v1.2, v2.0 + EDR, v2.1 + EDR, v3.0 + HS |
| Frequency Bands | 2.402 GHz to 2.480 GHz (79 RF channels @ 1 MHz spacing) |
| Modulation Schemes | GFSK (Basic Rate 1 Mbps), π/4-DQPSK (EDR 2 Mbps), 8DPSK (EDR 3 Mbps) |
| Max BR/EDR PHY Rate | 3 Mbps |
| Frequency Hopping Rate | 1,600 hops/sec (AFH–Adaptive Frequency Hopping) |
| Key Audio Profiles | A2DP (Advanced Audio Distribution Profile), HFP, HSP, AVRCP |
| Supported Audio Codecs | SBC (Mandatory), AAC, aptX, aptX HD, LDAC |
Basic Rate (BR) vs Enhanced Data Rate (EDR)
The original Bluetooth 1.0/1.2 specification used Gaussian Frequency Shift Keying (GFSK) at a Basic Rate (BR) of 1 Mbps. In 2004, Bluetooth 2.0 introduced Enhanced Data Rate (EDR), which kept GFSK for packet headers but switched to Phase Shift Keying (π/4-DQPSK for 2 Mbps and 8DPSK for 3 Mbps) for payload data, reducing power consumption and providing the bandwidth needed for stereo audio.
Connection Model and Power Characteristics
Bluetooth Classic relies on synchronous and asynchronous connection-oriented links (SCO/eSCO and ACL). Devices form 'Piconets' consisting of 1 Master and up to 7 active Slave devices. Because Bluetooth Classic maintains continuous active radio links, connection overhead and baseline power draw are significantly higher than Bluetooth Low Energy.