AMBICO
Manufacturers since 1955 of both wood and steel acoustic doors with steel frames. Steel doors from STC 33 - 59 and wood doors from STC 33 to 51 are available. Fire labeled products in wood or steel are tested compliant with NFPA-80 and certified by WHI. Stock units are available for immediate shipping.
Atrium Windows and Doors 
Designed to meet a wide range of acoustic requirements, Silent Guard® vinyl acoustic windows and doors represent the most sophisticated technology available in sound control fenestration. We combine superior noise abatement with the energy efficiency and maintenance-free beauty of premium vinyl windows. Our national presence and distribution system enable us to deliver these cutting edge products anywhere you need them.
Door Components
Founded in 1981, Door Components manufactures hollow metal and stainless steel doors with sound transmission control. They are STC rated up to 54 and tested in accordance with ASTM E90-90. STC doors are available in hollow metal and in stainless steel. Each door is custom manufactured to your exact specifications.
International Door, Inc.
Acoustical doors are available in Vertical Lift or Sliding configurations and are the perfect solution to a difficult task. Acoustical ratings of STC 53 or greater are available. All doors are custom manufactured to your project’s specific requirements and can be provided for manual or motor operation. Sound seals are provided for all acoustical doors.
Karpen Steel Custom Doors & Frames 
Quick-ship manufacturer of 12, 14, 16, & 18 gauge hollow metal doors and 12, 14 & 16 gauge hollow metal frames, temperature rise doors, wood-grained doors, dutch doors, acoustic assemblies, lead-lined doors and frames, pocket door frames, 2-piece slip frames, elevator sub-buck and shadow line frames, round top doors and frames, gothic arch frames, and more.
Krieger Specialty Products
Custom manufactured acoustical doors for live performance venues and industrial applications. 1-3/4" thick door available up to STC 53, and 2-1/4" doors up to STC 49, in both metal and wood veneer. 3" metal doors up to STC 55. Available for SCIF compliance. Clients include Disney Concert Hall, Kodak Theater, Seattle Symphony, General Motors and Bayer Laboratories.
Overly Door Company
For more than 50 years, Overly has been the industry leader in the design, testing and manufacturing of architectural acoustic door and window systems. Metal doors up to STC 57 and wood doors up to STC 49. Metal doors are available with up to 3-hour fire ratings. Wood doors with up to ¾-hour fire ratings.
Protective Door Industries
Swinging, horizontal sliding, vertical lift and multi-folding assemblies are available in PDI's line of Sonicbar® laboratory certified sound control doors with STC ratings starting at 48 and higher. From engine test cells to performing arts centers, PDI's technical staff can advise the best door solutions to meet the project's specific requirements.
Steel Door Institute - (SDI )
Non-profit association that represents 11 of the largest manufacturers of hollow metal doors and frames. Membership requires an extensive manufacturing audit to ensure adherence to ANSI standards. SDI develops rigorous standards for the use of sound control doors in the construction industry. SDI's website provides free standards and specifications, industry alerts, and FAQs.
Stiles Custom Metal 
Specify Stiles Audia™ for industrial, commercial & designer applications. Pre-engineered, custom designed assemblies, from STC 38 to 55, in wood, steel, stainless steel or bronze. Independently tested and certified to ASTM E90 and Fire Rated UL 10C. For immediate design assistance, contact our staff with over 40 years experience. Call 209 / 538-3667
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AMBICO
Manufacturers since 1955 of both wood and steel acoustic doors with steel frames. Steel doors from STC 33 - 59 and wood doors from STC 33 to 51 are available. Fire labeled products in wood or steel are tested compliant with NFPA-80 and certified by WHI. Stock units are available for immediate shipping.
Atrium Windows and Doors
Designed to meet a wide range of acoustic requirements, Silent Guard® vinyl acoustic windows and doors represent the most sophisticated technology available in sound control fenestration. We combine superior noise abatement with the energy efficiency and maintenance-free beauty of premium vinyl windows. Our national presence and distribution system enable us to deliver these cutting edge products anywhere you need them.
Door Components
Founded in 1981, Door Components manufactures hollow metal and stainless steel doors with sound transmission control. They are STC rated up to 54 and tested in accordance with ASTM E90-90. STC doors are available in hollow metal and in stainless steel. Each door is custom manufactured to your exact specifications.
International Door, Inc.
Acoustical doors are available in Vertical Lift or Sliding configurations and are the perfect solution to a difficult task. Acoustical ratings of STC 53 or greater are available. All doors are custom manufactured to your project’s specific requirements and can be provided for manual or motor operation. Sound seals are provided for all acoustical doors.
Karpen Steel Custom Doors & Frames
Quick-ship manufacturer of 12, 14, 16, & 18 gauge hollow metal doors and 12, 14 & 16 gauge hollow metal frames, temperature rise doors, wood-grained doors, dutch doors, acoustic assemblies, lead-lined doors and frames, pocket door frames, 2-piece slip frames, elevator sub-buck and shadow line frames, round top doors and frames, gothic arch frames, and more.
Krieger Specialty Products
Custom manufactured acoustical doors for live performance venues and industrial applications. 1-3/4" thick door available up to STC 53, and 2-1/4" doors up to STC 49, in both metal and wood veneer. 3" metal doors up to STC 55. Available for SCIF compliance. Clients include Disney Concert Hall, Kodak Theater, Seattle Symphony, General Motors and Bayer Laboratories.
Overly Door Company
For more than 50 years, Overly has been the industry leader in the design, testing and manufacturing of architectural acoustic door and window systems. Metal doors up to STC 57 and wood doors up to STC 49. Metal doors are available with up to 3-hour fire ratings. Wood doors with up to ¾-hour fire ratings.
Protective Door Industries
Swinging, horizontal sliding, vertical lift and multi-folding assemblies are available in PDI's line of Sonicbar® laboratory certified sound control doors with STC ratings starting at 48 and higher. From engine test cells to performing arts centers, PDI's technical staff can advise the best door solutions to meet the project's specific requirements.
Stiles Custom Metal
Specify Stiles Audia™ for industrial, commercial & designer applications. Pre-engineered, custom designed assemblies, from STC 38 to 55, in wood, steel, stainless steel or bronze. Independently tested and certified to ASTM E90 and Fire Rated UL 10C. For immediate design assistance, contact our staff with over 40 years experience. Call 209 / 538-3667
Steel Door Institute
Non-profit association that represents 11 of the largest manufacturers of hollow metal doors and frames. Membership requires an extensive manufacturing audit to ensure adherence to ANSI standards. SDI develops rigorous standards for the use of sound control doors in the construction industry. SDI's website provides free standards and specifications, industry alerts, and FAQs.