Sigma
Since 1970
Sigma Guitars was established in 1970 by C.F. Martin & Co. as an authorized Japanese and Asian manufacturing line to offer authentic Martin acoustic designs and tonewood configurations at an accessible price point. Over its storied 50+ year history, Sigma evolved through legendary eras—including vintage 1970s Japanese MIJ models made by Tokai and Kasuga, Korean production in the 1980s and 1990s, and the modern renaissance under Germany's AMI Musical Instruments (marketed as AMI Guitars in the US). Renowned for benchmark models like the DM-18, DR-28, and 000M-15, Sigma remains the premier choice for musicians seeking genuine golden-era dreadnought and orchestra acoustic tone on a realistic budget.
56
Years in Business
1.5M+
Guitars Sold
$15M+
Annual Revenue
Complete Sigma Guitar Price & Valuation Guide (2026)
Comprehensive market valuation ranges, mint vs used condition pricing, tonewood specs, and historical price trends for Sigma guitars.
Sigma Price Overview
Sigma covers a wide range of instruments from entry-level to professional models. Typical used prices vary by condition, series and year. Higher-end USA models and limited editions retain value better than mass-market lines, while rare or vintage pieces often command significant premiums.
When evaluating value, consider originality (pickups, hardware), structural condition (neck, frets, finish) and documentation (serials, receipts, setup reports). Price dispersion across platforms is common; local stores offer service and inspection, whereas online marketplaces provide broader selection and price transparency.
For detailed buying advice, model comparisons and condition-based pricing, read the full guide linked above.
Market Overview
Average Price
$480
+5.4% vs last year
eBay Listings
820
Active listings
Sold This Month
210
+4.8% vs last month
Price Range
$250-$1,200
Current market range
Data sourced from eBay, Reverb, and Guitar Center used listings
Sigma Timeline
C.F. Martin Founds Sigma
Martin established Sigma Guitars to offer Martin dreadnought designs crafted in Japan by premier luthier facilities like Tokai and Kasuga.
Inspection in Nazareth, PA
Martin implemented strict Nazareth quality control, shipping Japanese-made guitars to Pennsylvania for final setup before distribution.
Korean Production Transition
Manufacturing shifted to South Korea (Cort and Samick facilities), expanding production while maintaining Martin acoustic blueprints.
Martin Discontinues Original Line
Martin phased out the original Sigma branding to focus on its own Mexican-made X-Series and Road Series instruments.
AMI Guitars Revival
German distributor AMI GmbH acquired Sigma rights, relaunching the brand worldwide with solid tops, bone hardware, and vintage Martin spec homage.
Modern Acoustic Hegemony
Sigma stands as one of the most respected vintage and modern acoustic brands, offering flagship all-solid models (SDR-28, S000M-15) under $1,200.
Complete Sigma Product Lineup
Sigma guitars deliver authentic golden-era Martin acoustic blueprints, scalloped bracing, and bone hardware at an accessible price point.
Standard Series (Dreadnought & 000)
Solid Sitka spruce or mahogany tops with bone nut and saddle matching classic Martin dimensions.
Classic D-18 mahogany dreadnought tone ($320–$480 used)
Iconic D-28 style dreadnought with booming low-end and bone hardware ($420–$650 used)
All-mahogany 000 body with focused midrange and warm blues character ($380–$540 used)
All-Solid Master Series (S-Series)
Premium all-solid tonewood construction with dovetail neck joints and high-grade ebony appointments.
Flagship all-solid Sitka spruce and Indian rosewood dreadnought ($850–$1,150 used)
All-solid mahogany 000 auditorium for expressive fingerstyle ($780–$980 used)
Super jumbo flat-top with flamed maple back and sides ($650–$890 used)
Vintage Japanese & Korean Eras (1970-1995)
Original Martin-era imports with golden-era script logos and Japanese Kasuga/Tokai woodwork.
Collector-grade vintage Japanese dreadnought ($450–$750 used)
Aged resonant Japanese mahogany dreadnought workhorse ($350–$550 used)
"Sigma guitars deliver authentic golden-era Martin acoustic blueprints, scalloped bracing, and bone hardware at an accessible price point."
Model-Specific Buying Guide
Each model has unique characteristics that affect both tone and value. Here's what to look for when buying specific models.
The Benchmark Sub-$600 Martin D-28 Homage
Solid Sitka Spruce & Bone Hardware
Features genuine bone nut and compensated bone saddle paired with solid Sitka spruce top for rich harmonic bloom.
Dovetail Neck & Scalloped Bracing
Hand-fitted dovetail neck joint and scalloped X-bracing provide powerful low-end resonance and projection.
Unbeatable Used Price Retention
Maintains high liquidity on Reverb and eBay with fast turnover among bluegrass and folk musicians.
Pro-Tier All-Solid Acoustic Construction
All-Solid Tonewood Architecture
Solid Sitka spruce top paired with solid East Indian rosewood back and sides for maximum dynamic ceiling.
Grover Open-Gear Vintage Tuners
Premium vintage-style nickel Grover tuners with butterbean buttons for rock-solid tuning stability.
Direct Competitor to $2,000+ US Acoustics
Blind sound tests consistently place the SDR-28 on par with acoustic guitars costing more than double its price.