Capturing That Philadelphia Sound: A Technical Exploration of Sigma Sound Studios

1 Introduction

In his book What’s That Sound? An Introduction to Rock and Its History, John Covach makes the case that “…different recordings have what might be thought of as ‘sonic signatures’ – features that mark them in terms of where and when they were recorded, as well as by whom” (Covach 2009). This statement implies that music recordings can have uniquely identifiable sounds involving characteristics other than the music performance alone. Such characteristics can correspond to the perceived acoustic environment, specific recording technology, manipulation of technology and recording workflow procedures. Susan Schmidt Horning described the recording studio’s working environment by saying “…the studio became an instrument in its own right, which musicians and producer-engineering teams exploited to create new sounds, rather than simply trying to capture them” (Horning 2004). This statement describes an explicit desire to manipulate the studio environment for the creation of unique sonic characteristics. This sonic manipulation, and the skills necessary to control this manipulation, is further described by Horning. “Studio engineers, whether through miking, reverb, or mixing, are engaged in reconfiguring the sonic space of the studio. To do this effectively engineers build up not only tacit skills, but also a vocabulary to describe sound” (Horning 2004). This building of tacit skills hints at the insular nature of knowledge and training within the recording studio environment. Junior engineers traditionally learned skills from senior engineers and continued the chain of knowledge to others as they rose through the hierarchy of the studio.  Therefore, in smaller markets where the majority of music production was created in a selected few facilities, such as Philadelphia, Detroit or Muscle Shoals, there is a higher probability that these tacit skills could create uniquely identifiable sounds associated with each recording community.

The production of these identifiable sounds creates a new entity separate from the original musical performance. Or, as Pauline Stakelon writes, audio recordings “involve a translation of the sound into a new object, allowing for culturally contingent expectations about these sounds to be introduced into the mode of production” (Stakelon 2009). Therefore, the factors that create an identifiable sound become a culturally significant part of the studio’s recording output. This culture then sets in place the conditions whereby performance and recording procedures predispose the recording to having a similar identifiable sound. Though she was speaking specifically about cylinder recordings, Stakelon further describes this interrelation of performance and process. She writes: “While the performance necessarily dictates what is etched into the cylinder recording, the recording process determines why and how a performance will take place” (Stakelon 2009). It is then reasonable to expect the recording environment and procedures to have an affect on musical performance, not just the recorded sound.

Affect on performance and sound is central to the thesis of this paper. Beyond the musicians, songwriters, and producers of recorded music, can the creative procedures and technical environment associated with the recording studio provide an identifiable impact on the sonic characteristics of the recording studio’s output? Specifically, this paper asks the question: Did the acoustic environment, production workflow, and recording technology in place at the now defunct Sigma Sound Studios of Philadelphia provide an identifiable sonic imprint on the music that became known as Philadelphia soul?

1.1 Sigma Sound Studios and Philadelphia Soul

Located at 212 N. 12th St. in Philadelphia, Sigma Sound Studios was Philadelphia’s primary site of record production during the 1970’s and 1980’s. Founded in 1968 by Joseph D. Tarsia, it was at Sigma where producers and songwriters Kenny Gamble, Leon Huff, Thom Bell, the production team of Baker, Harris and Young, along with many others, created a musical form that placed Philadelphia in the spotlight of urban popular music. Characterized for its “impossibly lush strings that worked with the rhythm rather than against it” and “a slow shuffle drumbeat that recalled doo-wop rhythms” (Shapiro 2005), Philadelphia soul was formed from gospel and rhythm & blues and developed into funk and disco.

The team of studio musicians that created this brand of soul music at Sigma was known as MFSB (Mother, Father, Sister, Brother). Though this team of performers consisted of nearly forty musicians, it was a tight-knit, familial group that inspired and supported each other to perform at their best. Drummer Earl Young, Bassist Ronnie Baker, Guitarists Norman Harris, Bobby Eli, Roland Chambers and T. J. Tindal along with Pianist Leon Huff and Vibraphonist Vince Montana formed the band behind such recording artists as the O’Jays, Harold Melvin and the Blue Notes, The Delfonics, The Three Degrees and Teddy Pendergrass, to name just a few. Augmented by a string section led by Don Renaldo and a powerful horn section, MFSB played on such hits as “If You Don’t Know Me By Now”, “Back Stabbers”, “Me and Mrs. Jones” and “When Will I See You Again”. There was such cohesion within this ensemble that they released eight albums under their own name on Philadelphia International Records. This included the song “TSOP (The Sound of Philadelphia)” which became the theme song for the popular American television show Soul Train.

With such a vast musical legacy, it is easy for any discussion regarding Philadelphia soul music to focus on the musical and songwriting talent that created it. It is impossible to imagine this genre without immediately thinking of Earl Young’s driving high hat, Ronnie Baker’s deep and moving bass parts, Kenneth Gamble’s poignantly expressive lyrics or the thick string arrangements that place this music on a grand stage. Yet, when speaking of Philadelphia soul, it is also impossible to imagine it without its place of creation, Sigma Sound Studios. It was here that a team of engineers and technicians captured these musical performances and put their hand on the creation of Philadelphia soul. Engineers Joseph Tarsia, Arthur Stoppe, and Carl Paruolo, to name just a few, were instrumental in manipulating the technical environment and studio workflow that allowed the musicians and producers of Philadelphia to create their art. Tacit engineering skills handed down from mentor to apprentice helped each of these engineers master the art of microphone placement, equipment and tape machine usage and audio mixing. In the case of Sigma, Tarsia set the stage as the founder and chief engineer. Each engineer’s development had a direct lineage back to Tarsia. With an electronics background, Tarsia first worked in the research department of the Philco Corporation and then developed his audio engineering skills at Cameo Parkway Studios prior to purchasing and founding Sigma. With Tarsia’s guidance, a team spirit and a strong commitment to service, Sigma set a high standard for technical expertise and professionalism.

Along with the technical expertise found at Sigma, the recording studio environment also played a large part in creating Philadelphia soul music. As the setting for these musical performances, Sigma’s acoustical environment left an indelible mark on the sound of Philadelphia soul. The cozy space of Sigma, how musicians were placed in that space and the resulting microphone spill were all part of the signature Sigma sound. Sigma’s environment and policies also had a psychological impact on performances. For instance, Sigma once ran an advertisement that, contrary to most studios that touted their equipment lists, simply stated that it maintained clean bathrooms. Joseph Tarsia made it clear that the studio was to be respected by all participants and that it was a professional work environment. Musicians and engineers took notice and came prepared to work hard and perform to their best ability while embracing the ethos of Sigma’s management.

1.2 Methodology

To illustrate the influence of Sigma Sound Studios on the sonic signature of Philadelphia soul music, archival materials from the Drexel University Audio Archives were examined. Specifically, multi-track audiotapes from The Sigma Sound Studios Collection were studied as they offer a unique opportunity to dissect recordings into the individual elements of a music production. These individual elements consist of the original recordings of each instrument or voice and allows for critical examination of any imprinted acoustical environment, technical processing or workflow constraints. These explorations, however, were further informed by exclusive interviews with Sigma’s founder and chief engineer Joseph D. Tarsia. These interviews were performed in September and November of 2011 on the campus of Drexel University. Both interviews provided a wealth of information and insight regarding the operations and procedures of Sigma Sound Studios. Tarsia not only founded Sigma Sound Studios, he also directed operations and set forth recording procedures that, by becoming part of Sigma’s culture, were instrumental in creating the famous Philadelphia sound.

2 Acoustic Environment

The acoustic environment in which a recording takes place is able to provide an identifiable character to an audio recording. It is hard to imagine a great orchestral recording without a concert hall playing a key role in its sonic characteristics. However, an acoustic environment is not always as obvious as a concert stage. William Moylan refers to this condition as “perceived performance environment”. This environment “is the overall space where the music ‘performance,’ the music ‘recording’ is heard as taking place” (Moylan 2007). This description of the performance environment shows how the perceived environment is not necessarily based in reality. The acoustic environment of a recording can therefore be the creation of both actual acoustic environments as well as manufactured acoustic environments. Coupled with the modern popular music production trend of close microphone positioning and the actual acoustic environment can be further diminished in importance, relying more on a manufactured environment.

Sigma Sound Studios started at the crossroads of traditional and modern popular music production. Therefore, the recordings created there had the potential to be influenced by both actual and manufactured acoustic environments. When asked what influence the actual acoustic environment of Sigma had on recordings, Joe Tarsia said:

“The room gave you something. In other words, with all the technology today, you win some things and you lose some things. We won the fact that we can make great sounding records anywhere, but what we lost was the personality those records had, because, the room gave a personality. The same thing with Sigma, the same thing with Motown, the same thing with the studios in Memphis and Muscle Shoals, those rooms gave a sound and a personality that you don’t have anymore. You know, the Memphis horns and the Motown rhythm section… the ambiance of those rooms is what gave those records a personality.”

However, when asked about the importance of this acoustic environment, Tarsia provided this comment:

“My first boss said, ‘The song is the horse on which the artist rides to fame.’ And that’s true. You know, the driving force for why people buy records… I mean, sound is somewhere down the middle.  To me it’s the song, the artist, the arrangement, the studio, in that order.”

Here, Tarsia expresses that the musical components of a recording outweighs the studio environment with regards to its success. While this philosophy is widely accepted among many record production professionals, Tarsia makes it clear that the acoustic environment does provide a sonic “personality”.

While the room’s acoustic properties contribute to this personality, so can a facility’s manufactured acoustic environment. This manufactured acoustic environment manifested itself at Sigma Sound Studios during the early years through a purpose-built echo chamber. This echo chamber was in place when Tarsia bought the facility in 1968. The space was previously Rec-O-Arts; a mono-only recording facility that was built before the availability of commercially produced reverberation units. This echo chamber was the primary time-based effect used in the early days of Sigma. However, with the influx of reverberation units to the market in the late 1960’s such as the popular EMT Plate, Tarsia removed the echo chamber in 1972 to provide more recording space for the studio. Joe Tarsia described the unique characteristics of this echo chamber:

“The studio was forty-feet long and next to it was a room that was about six-feet wide, forty-feet long and twelve-feet high and it had a speaker and a mic in it. And it was a beautiful echo chamber and it had a certain low-end warmth to it. I was trying to figure out why and it was because [it was a] mono studio – they (musicians) played and he (engineer) put echo on it, and a lot of the low end in the echo chamber came through the wall.”

This acoustical transfer of low frequency energy through the wall separating the studio and the echo chamber, as Tarsia described, was only possible during the recording of live performances. In other words, echo had to be applied during the actual performance to allow for sound from the live room to contribute to the echo chambers output. Therefore, the unique warmth of the Sigma echo chamber would only be apparent if used in the context of ensemble performance recording that was still common in popular music production in the late 1960’s. This chamber can be heard on Holly Maxwell’s recording of the song “Never Going To Love Again”. Recorded by Tarsia in December of 1969 on one-inch eight-track tape, the drum microphones were combined to one track with added reverberation from the echo chamber. While Tarsia suggests that the added reverberation might also contain some EMT plate reverb, the low-end warmth from the echo chamber is apparent on the bass drum hits, which are clearly present in the echo decay of the recording. Because of the desirable affect that the Sigma echo chamber provided, ensemble performance was a preferred workflow in music production at Sigma.

3 Workflow

While the echo chamber affect supported the use of ensemble recording, so did the desire of record producers to capture groove-oriented recordings. Capturing a performance that “felt” right was paramount to the production of funk, soul and rhythm & blues and having musicians perform together helped accomplish this goal. While creating the desired performance environment, this type of workflow presented some challenges for Sigma engineers. The primary challenge was the reduced isolation between instruments that occurs when multiple instruments are placed within the same acoustic space. Couple this with the relatively small recording space at Sigma and the lack of isolation became a signature characteristic of the sonic output of the studio. Tarsia had this to say about the workflow within Sigma’s recording environment:

“Kenny Gamble, Leon Huff, Thom Bell… the way our rhythm section worked, they wanted to feel each other. They wanted to be close. Ronnie Baker, the bass player and Earl Young, the drummer, wanted to sit right next to each other. Ronnie wanted to look at Earl’s foot on the bass drum so he could synch with him on the bass. So, our guys were used to working close. That meant we didn’t have great isolation. But that was good in my mind.”

Due to the potential comb filtering that occurs when there is a phase relationship difference between combined audio sources, many engineers view this lack of isolation that Tarsia mentions as a detriment. This view has led to the common modern practice of close microphone placement techniques and using greater isolation structures within the recording studio, such as separate recording spaces for performers or recording performers individually. However, while it might take more effort to achieve good results, Tarsia preferred using the spill between microphones as a way to add natural ambience to a recording. For instance, Tarsia used spill to achieve his desired drum sound.  Tarsia had this to say about learning to record drums:

“I was always troubled because when I was at Cameo [Cameo Parkway Studios], I tried to get this big drum sound and I always had a problem. It was always this big [gestures small]. I’m trying to fight through it and I went to a session at Bell Sound… the engineer was going through muting stuff and listening and making adjustments and I heard this big, fat sound. And he soloed the drum mics, and that sounded just like my drums.  Then, he soloed the strings, and there was the drum sound.”

Therefore, ensemble recording, where spill from many open microphones could be used for a desired ambient affect, was a large part of the Tarsia drum sound. As mentioned before, Sigma’s recording space was not very large. So, if an entire rhythm section of drums, bass, guitars, piano, plus vibraphone, string section and horn section are recorded together, large amounts of spill is inevitable. This type of session can be heard on the 1971 Len Barry recording “Girl You’re Too Young”. On this recording, the sound of each instrument is incomplete without the spill from the other instruments. The drums are prominent in the string microphones. The guitars are audible in the piano microphones. When the record was mixed, this lack of isolation informed the final balances and the overall ambient nature of the recording. However, this was a known quantity that was manipulated from the initial recording session set-up. Each player was positioned in a very specific proximity to each other while microphone placement was critical in achieving the correct balance between direct sound and spill.

While full ensemble recording was Tarsia’s preferred method, Sigma’s small size did have its constraints on workflow. For instance, Philadelphia soul music is characterized by big and lush string arrangements. However, available space prohibited the use of large string sections. So, it was common to use smaller string sections and enlarge the perceived performance by double tracking them. Tarsia describes his process of recording strings:

“The Philadelphia string section was 6, 2 and 1. And I would use two mics on the six violins, a microphone on the violas and a microphone on the cello. So, I developed this system where I put speakers, little tiny speakers, around the string section. Of course, when you recorded the strings, there were these speakers playing in the microphones.  So, we always doubled the strings. Nobody moved, I threw all the phase reversal switches; we recorded the strings again, the speakers are now out of phase and the leakage cancels.”

This method allowed the string players to perform without headphones, which, according to Tarsia, the string players preferred as they felt they could provide a more natural performance. However, this method was not possible if the first pass was recorded live with the rhythm section. The additional spill from the rhythm section would not be cancelled with the doubled track. Therefore, this method was an evolution of workflow from the previously preferred method of ensemble recording. A good example of this technique can be heard on the previously mentioned Holly Maxwell recording, “Never Going To Love Again”. The strings are recorded onto one track of the one-inch eight-track tape. However, the original performance and the doubled performance were combined to create this single track. The speaker technique, as Tarsia described, was used and minimal leakage is apparent in the recording.

A further evolution in workflow started to take place once available track counts increased. On the 1975 Terry Collins recording, “Hold Hands With One Another” on Silver Blue Records, the string parts are not only doubled, but also tripled. Produced by Bobby Eli and Joel Diamond and engineered by Dirk Devlin, this recording was made on a newly purchased twenty-four track machine. This increased track count allowed for additional elements to be recorded without the need for bouncing tracks together. So, in this instance, it was determined to increase the perceived size of the string section by adding yet another track. However, instead of an identical triple that matched the first two passes, the tripled track was arranged for the inclusion of additional parts. In this case, the string parts were written in a lower range and served to thicken the string arrangement and make the apparent string section perceptually larger.

4 Technical Influence

Guided by Tarsia’s love for technology and his desire for Sigma to remain state-of-the-art in a competitive market, Tarsia was an early adopter of new technology. For instance, Sigma was an early adopter of sixteen-track and twenty-four track tape machines. According to Tarsia, Sigma was the second recording studio in the United States to have twenty-four track recording capabilities. Sigma was one of the first studios in the world to incorporate Dolby™ Type A Noise reduction systems into a multi-track configuration. Sigma was also one of the first studios in the United States to install a working console automation system (Allison Automation), which allowed mix engineers to save, update and playback fader moves, and incorporate it into its daily workflow. However, it is difficult to point to these technologies as having an identifiable sonic character. While these technologies certainly affect workflow, and workflow can have an affect on sonic character, these technologies were in part developed to decrease the sonic imprint on record production. For instance, the implementation of a noise reduction system was an effort to make the recording medium as sonically inert as possible. Striving for this sonic transparency was one of Tarsia’s guiding principles. Tarsia further describes his recording philosophy:

“After procedures that gave the best sound, my philosophy was – the recording process should stay out of the way of the creative process as much as possible. We were there to capture what the guys were doing. And, in fact, in the initial recording, we tried to treat or to color the recording as little as possible.”

This philosophy of keeping technology out of the way of creativity allowed record producers and musicians to have control over the recording process as much as possible. While technology is not perfectly transparent, the acoustic environment and workflow have a more concrete influence on the sonic characteristics of the recordings made at Sigma.

5 Conclusions

The acoustic environment, workflow and technology all have influence on the sonic characteristics of a musical recording. In the case of Sigma Sound Studios, this paper has described examples of its sonic influences on Philadelphia soul music. While this influence is undeniable, it is also very difficult to define as influences are often bidirectional and multifaceted. For instance, while the acoustic environment and studio workflow can have a sonic impact on a recording, technology and production philosophy can influence the acoustic environment and studio workflow.

Sigma Sound Studios’ unique echo chamber and cozy recording space created the acoustic environment and setting for decades of hit records. Music production workflow, as established by Tarsia to take advantage of instrument spill and technological constraints, provided the ability for record producers to realize their vision and to create smooth and lush soul recordings. Tarsia’s desire for technological superiority provided the tools necessary to enable musical creativity by all participants and, not insignificantly, produce hit records. While this paper outlines a few examples of Sigma’s sonic impact, there are many more to be discovered within the corpus of Sigma’s output.

In discovering this impact, a number of questions remain to be explored. Are the sonic affects of Sigma conclusively definable? If so, how is the best way to discover and define those affects? When asked about the sonic impact Sigma Sound Studios had on Philadelphia soul music, record producer and guitarist for MFSB Bobby Eli replied, “You could take MFSB anywhere and we would always sound like Philadelphia. However, when we played at Sigma, we sounded better, more precise.” When asked why, he replied, “I don’t know, we were just at our best”. In a casual discussion with record producer Tom Moulton, he attributed Sigma’s characteristic sound to Tarsia’s technological leadership. However, examples of this affect were not stated nor could be conclusively found. This inconclusiveness leads the author to this question: Is there greater value in deconstructing individual recordings rather than the entire Sigma Sound Studios repertoire? In other words, is there a common thread in Sigma’s output that can be conclusively framed as a sonic signature, or does each recording tell a new and unique sonic story? These questions will be explored with further research into the recorded legacy of Sigma Sound Studios and its affect on Philadelphia soul. Regardless of conclusive results, inquiries into record production procedures used at Sigma uncover valuable insight into the inner working dynamics of a highly prolific and influential recording facility.

About The Author

Toby Seay

Drexel University


Joseph D. Tarsia, Founder and Chief Engineer – Sigma Sound Studios

Bobby Eli, Guitarist – MFSB, Record Producer

Tom Moulton, Record Producer, Re-mixer

MADDragon Studios

Ryan Schwabe, Manager

Drexel University’s Paul F. Herron TV Studios

Dave Culver, General Manager

Chelsea O’Rourke, Sr. Production Manager

Drexel University Audio Archives

Brian Kantorek, Archival Assistant

Leanne Fallon, Graduate Assistant

Ted Fletman, Preservation Intern

Kazia Nowacki, Archives Volunteer


Covach, John (2009). What’s That Sound? An Introduction to Rock and Its History, second edition. New York. W.W. Norton & Company.

Horning, Susan Schmidt (2004). Engineering the Performance: Recording Engineers, Tacit Knowledge, and the Art of Controlling Sound. Social Studies of Science 34(5), 703–31.

Moylan, William.  2007.  Understanding and Crafting the Mix: the art of recording, second edition.  Boston.  Focal Press.

Shapiro, P. (2005). Turn The Beat Around: The Secret History of Disco. New York, NY: Faber and Faber, Inc.

Stakelon, Pauline (2009). A Sound that Never Sounded: The Historical Construction of Sound Fidelity. Convergence 15(3), 299.


Len Barry, ‘Girl You’re Too Young’. Vanguard Records, 1971.

Terry Collins, ‘Hold Hands With One Another’. Silver Blue Records, 1975.

Holly Maxwell, ‘Never Going To Love Again’. Smit-Whit Records, 1969.

Harold Melvin & The Blue Notes, ‘If You Don’t Know Me By Now’. Harold Melvin & The Blue Notes. Philadelphia International, 1972.

MFSB, ‘TSOP (The Sound of Philadelphia)’. MFSB. Philadelphia International, 1973.

O’Jays, ‘Back Stabbers’. Back Stabbers. Philadelphia International, 1972.

Billy Paul. ‘Me & Mrs. Jones’. 360 Degrees of Billy Paul. Philadelphia International, 1972.

The Three Degrees, ‘When Will I See You Again’. The Three Degrees. Philadelphia International, 1973.