HEADSET MICROPHONE COMPARISON - SPEECHWARE’SNEW FLEXYMIKE DEC VS NEW SENNHEISER ME3-IIObjectiveTo compare SpeechWare’s new, second-generation, FlexyMike Dual Ear Cardioid (DEC) headsetmicrophone against the new Sennheiser ME3-II headset microphone for accuracy in DragonNaturallySpeaking.BackgroundSpeechWare of Brussels are making design improvements to their FlexyMike DEC headsetmicrophone. The new model will have the same capsule as the existing model but will feature a‘telescoping’ or adjustable headband and vertical cable connector in one side for improved wearercomfort. The following images show the improved FlexyMike DEC design --note the “intriguing” 3rdimage in which the headset is used as a Desktop microphone with very long range dictation (!)thanks to the unique SpeechWare USB MultiAdapter under Green LED or light:During the FlexyMike DEC redesign phase, Sennheiser announced that they had replaced their ME3EW headset microphone (a long-standing favourite with the speech recognition community) with anew version called the Sennheiser ME3-II.Old Sennheiser ME3-EWReplacement Sennheiser ME3-IIVersus the old Sennheiser ME3-EW, the Sennheiser ME3-II has a shorter microphone boom, theshape of the element in contact with the face is now round and not tear-dropped shaped and themicrophone capsule has a metal grille housing on both sides. The Sennheiser ME3-EW had an allplastic microphone capsule enclosure.Sennheiser say that the microphone capsule itself in the new Sennheiser ME3-II is identical to themicrophone capsule in its predecessor Sennheiser ME3-EW. However, I compared the twomicrophones by making a sound recording in Windows 10 with both microphones connected to the1

microphone in port of the computer and set at the same microphone in sound level. I found that thenew Sennheiser ME3-II was significantly ‘less hot’ (i.e. produced less sound) than the previousSennheiser ME3-EW and was also significantly less hot than the FlexyMike DEC (recording filesavailable on request). There was no difference in the sound levels either Sennheiser model whenconnected to the computer with a Buddy 7G USB Sound adapter. In this case, the new SennheiserME3-II gave the same loud and clear sound as did the Sennheiser ME3-EW.Tests were carried out compare the accuracy in Dragon Naturally Speaking of the upcoming newFlexyMike DEC model to the accuracy of the new Sennheiser ME3-II.Testing protocolWord recognition accuracy in Dragon Naturally Speaking was evaluated under exact identicalconditions for each microphone using my ‘mouth simulator’ test.Specific test parameters were as follows:Dragon NaturallySpeaking versionLanguage modelWindows versionComputer specificationDragon Professional Individual 14UK EnglishWindows 10 (64-bit), build 10586 HP ENVY dv6 Notebook PC Intel i7, 2.3 GHz quad core 8 Gb RAM Samsung 840 EVO solid-state drive (SSD) Soundcard – IDT High Definition AudioFor the testing, Dragon Professional Individual 14 was chosen as the Dragon version rather than thelatest Dragon Professional Individual 15 version. This version was chosen because our mouthsimulator test protocol is based on giving each microphone exactly 5 minutes of enrolment training.Enrolment training has been removed in the latest version of Dragon (Professional Individual 15) andhas been replaced by ‘deep learning’. Basically, in version 15, Nuance say that dictating severalhundred lines of text, making the necessary corrections and running the Acoustic and LanguageModel Optimiser does the same job as enrolment training in previous versions.The following setups were tested:MicrophoneAudio input sound connectionSennheiser ME3-EW with Speech RecognitionSolutions Sennheiser 6” adapter cableSennheiser ME3-II with Speech RecognitionSolutions Sennheiser 6” adapter cableSpeechWare FlexyMike DECMic in (sound card)Sennheiser ME3-EWBuddy 7G USB sound adapterSennheiser ME3-IIBuddy 7G USB sound adapterFlexyMike DECSpeechWare USB MultiAdapter in Blue LEDmodeMic in (sound card)Mic in (sound card)2

User profiles in DPI Individual 14To explain the choice of testing in Blue LED mode in of the SpeechWare USB MultiAdaptermentioned in the last row of the above table --this sound adapter is the only USB adapter supportinga very ‘hot’ long range dictation mode (under Green LED mode) meant for the USB TravelMike andless sensitive headsets, as well as for using the FlexyMike DEC as a desktop microphone too (!),which is an amazing option if ever you are tired of wearing the microphone after many hours ofcontinuous dictation. SpeechWare obviously recommends the Blue LED (normal range dictationmode) for the FlexyMike DEC, when used in a normal conventional way.Note that the actual SpeechWare FlexyMike DEC model tested was the current design model ratherthan the actual new design model. SpeechWare assured us that the microphone capsule in the newdesign will be exactly identical to microphone capsule in the current design.For testing the Sennheiser microphones with a USB Sound adapter, I chose to use the Buddy 7G USBsound adapter. This is my preferred sound adapter for use with the Sennheiser ME3 as it has aproven track record of producing high accuracy and I have never received any negative customerfeedback with this combination.3

ResultsThe accuracy results (with a UK English language model) were as follows:Accuracy (%)Old SennheiserME3-EW with 6”adapter cable to mic- inNew SennheiserME3-II with 6”adapter cable to mic- inSpeechwareFlexyMike DEC tomic - inOld SennheiserME3-EW with Buddy7GNew SennheiserME3-II with Buddy7GFlexyMike DEC(original design)with SpeechWareUSB MultiAdapter inBlue LED (normalmode)Dropped wordsAverageaccuracy (%)AveragedroppedwordsNonoise98.8With 70 dBAnoise98.7Nonoise0.6With 70dBA .60.898.50.7* Best average results in red (new ME3-II and FlexyMike DEC results)Conclusions1. In the case of sound card only (mic – in) audio connection, the Speechware FlexyMike DEC wasmarginally better than the recently introduced Sennheiser ME3-II in terms of accuracyperformance.2. The FlexyMike DEC with SpeechWare USB MultiAdapter in Blue LED mode was identical to theSennheiser ME3-II with Buddy 7G in terms of accuracy performance. However, setting theSpeechWare USB MultiAdapter in Green LED mode allows the FlexyMike DEC not only to be usedby people with very soft voices but also, as a rather unique long-range dictation desktopmicrophone (!).3. In the case of a sound card only audio connection, the accuracy of the replacement SennheiserME3-II appears to be reduced versus its predecessor Sennheiser ME3– EW but accuracy appearsto be the same when connected to the computer via a Buddy 7G USB sound adapter.4

4. Since performance of the three headsets is top notch, headband design, functionality, comfortand weight may play a substantial role in the final choice. In this context:Ancillary criteriaNew ME3-IIHeadband designErgonomicsComfortWeightGoodGoodHeavyOld ME3-EWFixedGoodGoodHeavyNew FlexyMike DECAdjustableBestBestLighterFinal thoughtsI am a little concerned about the apparent reduction in sound input levels with the Sennheiser ME3II when connected to a PC sound card via the mic – in port. I have always told my customers that theSennheiser ME3-EW is capable of delivering good results when a speaker needs to speak in a lowvolume into the microphone (e.g. a user in an open plan environment who does not want to annoytheir neighbours with sound of his or her dictation). I may have to revise this advice with thereplacement Sennheiser ME3-II.Based on my findings, I will advise customers to only use the new Sennheiser ME3-II with a soundadapter such as the Buddy. However, this concern does not appear to be relevant with the FlexyMikeDEC as it produces a substantial sound input when connected via the microphone in port of thecomputer even when running with the SpeechWare USB MultiAdapter under Blue LED normal mode.Dr Peter Maddern16th January 20175