Telecommunications Industry Association
TR41.9-12-02-011-L
Document Cover Sheet
Project Number
PN-3-3602-RV4-AD1 (Addendum to TSB-31-D)
Document Title
Text Changes for ROLR/RLR Relationship in Alternative Test Procedure of
Clause 14.2.6
Source
Whitesell Consulting
Contact
Stephen R Whitesell
2 Shannon Ct
Howell, NJ 07731
Distribution
TR-41.9
Intended Purpose
of Document
(Select one)
X
Phone: 732 751 1079
Fax:
Email: swhitesell@ieee.org
For Incorporation Into TIA Publication
For Information
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The document to which this cover statement is attached is submitted to a Formulating Group or
sub-element thereof of the Telecommunications Industry Association (TIA) in accordance with the
provisions of Sections 6.4.1–6.4.6 inclusive of the TIA Engineering Manual dated October 2009, all
of which provisions are hereby incorporated by reference.
Abstract
Several individuals have noted problems with the simple relationship for determining whether measured
RLR values comply with Part 68 ROLR requirements as discussed in the alternative test procedure clause
14.2.6 for receive volume control measurements. Text is proposed for modifying the clause to provide
more details about the historical background of the stated relationship along with cautionary wording and
suggestions for establishing the appropriate relationship for specific handset designs.
v1.0 – 20050426
Telecommunications Industry Association
TR41.9-12-02-011-L
The following are proposed modifications to the text of clause 14.2.6:
14.2.6 Alternative Methods
Although 47 C.F.R., 68.317 specifies the receive volume control requirement in terms of ROLR as
defined in IEEE 661-1979 (R2008), current industry standards TIA-470.110-C (replaces TIA-470-A) and
TIA-810-B (replaces TIA-579) have shifted to measuring receive loudness in terms of Receive Loudness
Rating (RLR) as defined by ITU-T Recommendation P.79.
Annex G of TIA-470.110-C provides the following relationship between these two loudness rating
measures:
ROLR (IEEE 661) = RLR (ITU-T P.79) + 51 dB
This relationship was derived from measurements of the G-type handset used on the Western Electric
500-type telephone and measured with an ITU-T Recommendation P.57 Type 1 artificial ear (IEC 318
coupler). The relationship may differ when testing other types of handsets that do not seal on the knifeedge of the Type 1 ear or when a Type 3.3 artificial ear with a flexible rubber pinna is used for the testing
as required by the current industry standards. In this case, both the ROLR and RLR values should be
calculated from the same measured frequency response curve to determine the appropriate relationship
between the two for the specific combination of handset geometry and artificial ear. The resulting
relationship may then be used to determine if RLR values obtained according to the methods in TIA470.110-C and TIA-810-B comply with Part 68 criteria specified in terms of ROLR.
For digital telephones, the sinewave generator and reference codec may be replace by a means for directly
generating a digital bit stream in the appropriate format that is equivalent to the digital bit stream that
would be produced from the reference codec with the specified sinewave signal applied.
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