exceptional voices of female singers (non-classical)

What I'm talking about here is what critics of classical singing refer to as "the instrument": the exceptional beauty or uniqueness of the timbre of the voice qua voice.  For the moment, put aside preferences w.r.t. repertoire, interpretation, performance, style, delivery, etc., and just consider the *sound* of the voice.  We're *not* talking about favorite female artists here, because that kind of preference is based on a whole amalgam of factors.

I suspect some of the top figures in the category I've tried to define often aren't very popular among audiophiles, because of those many other factors.

My first three nominations: Barbra Streisand, Linda Ronstadt, Eva Cassidy.

Oh there are many, but for beauty, two that come to mind are Janis Ian and Alison Krauss.
For uniqueness, Rickie Lee Jones and Ella.
I never paid much attention until Samsung started doing those ads using the "Similau" song, but I've come to really like Peggy Lee's singing style.
Karen Carpenter
Neko Case
Rhiannon Giddens
Tift Merritt
Judy Collins
Jenny Lewis
Carly Simon
K D Lang
Alison Moyet
Based on the purity and sheer beauty of her voice, I would cite Judith Durham, best known as the lead singer of The Seekers although she has had a distinguished solo career as well.

Following is a brief excerpt of comments about her provided by a British gentleman whose bio is shown at the end of an article he wrote entitled Judith Durham: The Voice of the 20th Century. Obviously some of what he has to say in this paragraph and in the rest of the article is debatable, as well as being subjective to a considerable extent, but his comments are not without foundation IMO.

Judith Durham (of the Seekers) is the greatest of them all. The voice of the twentieth century, in my not very humble opinion. Clarity, spine-shivering (I’ve already used “spine-tingling” and I’m all for a bit of variety), astonishing purity – all that is obvious straightaway. But listen to The Carnival is Over or the amazing Just a Closer Walk and you hear a vocal beauty which is unique and reaches a level no one else can get near to. Callas is just a tear-jerker by comparison; Carpenter just a female crooner; Piaf just a screeching Gallic banshee. Judith Durham combines a bold, even brash, confidence in her own ability with a deeper humility which lends her remarkable sound an even more profound character.

Best regards,
-- Al

I listened to an interview of Judy Collins where they were taking callers..a caller was explaining that in school, his teacher had a program that could show waveforms and compare voices with them. According to the caller, his teacher said Judy’s voice showed almost perfect form. FWIW.
Emmylou Harris, Iris Dement, Julie Miller, Patty Loveless, Rhonda Vincent, Alison Krauss, Rosanne Cash, Carter Carter, Dolly Parton, Tammy Wynette, Darlene Love, Maria Muldaur, Joan Osborne, Maryann Price, Lou Ann Barton, Aimee Mann.
Maureen McGovern has one of the most "pure" tones I've ever heard. Listen to her interpretations of Arlen tunes if you can find the cd.
A second on Alison Krauss.

Add Carmen Gomes and Joan Armatrading. And exceptional recordings for Carmen.
Chantal Chamberland, Katie Melua, Kelly Sweet, Norah Jones..... they sound pretty sweet, and just for pure angelic sound try Jackie Evencho’s Awakening CD or some Nana Mouskouri
Another vote for Holly Cole, her album, Temptation, is a must have.


And Joan Armatrading, how can you not like these lyrics,


The future may be bright for Chloe Kohanski. I think she has the potential, but time will tell.



A second for Nancy Wilson and Ella.
Also: Lani Hall ( Sergio Mendes, et al );
         Lyn Stanley;
         Nicki Parrott;
         Laura Nyro, and
         Vanessa Fernandez
Stevie Nicks
Natalie Merchant
Patricia Barber
Brandi Carlisle
Mary Bell
Joan Osborne
Lisa Fowler
Abbey Lincoln
Kathleen Edwards
Grace Slick
Tift Merritt
Given that the question focuses exclusively on "the instrument," and excludes repertoire etc., I'll add Connie Francis to my previous suggestion of Judith Durham.

Best regards,
-- Al

Love the voice of Jennifer Rush, however these days the recording engineers put so much reverb on the voices that it is hard to tell the true sound of a voice.
Loretta Lynn
Shelby Lynn
Mariah Carey
Alanis Morrisette
Whitney Houston
Norah Jones
Linda Ronstadt

Holly Cole. If you have never listened to the Trio's "Temptation" do so. "Girl Talk" is another of where her voice is so intimate as to make you think she is singing for you alone.
I could probably add another voice or two every day for quite awhile (I love female voices), but above left out a few that simply MUST be included: Aretha Franklin, Arlene Smith (of The Chantels---you have GOT to hear her sing "Maybe"), Brenda Lee, Peggy Lee, Wanda Jackson, Ruth Brown, Lucinda Williams, Bonnie Raitt, Kasey Chambers, Dusty Springfield, and Judy Garland.
For me it's all about the emotion and soul:

The greats include:

Etta James.
Lucinda Williams.
Sandy Denny.
Aretha Franklin.
PP Arnold.
Anne Peebles.
Irma Thomas.
Emmylou Harris.
Allison Moorer.
Dusty Springfield.
Maggie Bell.
Gloria Jones.
Bessie Smith.
Billie Holiday.
Wanda Jackson.
Lisa Kekaula.
Koko Taylor.
Mavis Staples.
Patti Smith.
and a few more.

They do not include:

Mariah Carey.
Celine Dion.
Whitney Houston.
Diana Krall.

Who have no soul.
Apparently none of you have heard Tierney Sutton, a very classy jazz singer with incredible backup musicians. She recently did an album of classic Joni Mitchell songs with Mark Summer and Turtle Island String Quartet “After Blue “. Give her a listen!

I'll check out Judith Durham All, because I trust you, and I certainly agree with Connie Francis, she's a natural.

I would like to add Mary Fahl of October Project. A beautifully pure but smoky voice. I really don't know of another voice like hers. 

Thanks very much, John (Roxy54). Here are some videos of Judith Durham with The Seekers, which provide about as good an indication of the quality of her voice as one is likely to find in a YouTube video of a 1960s recording:

"The Carnival Is Over" (composed for them by Tom Springfield, Dusty’s brother, who wrote a lot of their hits):

"Someday, One Day" (composed for them by Paul Simon):

"Love Is Kind, Love Is Wine" (composed by Bruce Woodley, the guitarist on Judith's right):

Best regards,
-- Al

On last CBS Sunday Morning show, was introduced to singer
Marilyn Maye. Ms. Maye sings in the classic style of the 30s and 40s.
She was hitting her stride at the time of the British Invasion in the mid 60s and got lost in the shuffle. She is till going strong, in her 90s, and can be found on YouTube.
Hi Al,
Thanks for the heads up. I'm a little ashamed to admit that at 63 I have heard of the Seekers, but nothing beyond that except for maybe Georgy Girl. I just ordered a best of CD with the songs you mentioned from Amazon prime for 8.99.
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Damn, how could I have left out Patsy Cline?! And Carole King?! And Big Mama Thornton (the female Howlin’ Wolf)?! Etta James, Eartha Kitt, Irma Thomas, Patti Page, and so many more.

Some of the same as mentioned by others and some I love I didn't see mentioned;

Sandy Denny
Alison Krauss
Laura Nyro
Dionne Warwick
Joni Mitchell
Anaïs Mitchell (No relation) Saw her live recently...unbelievable beauty in her voice, great songwriting/guitar and overall vibe, beautiful woman, inside and out;