Used on Grohl's vocals for "The Pretender", as stated by mix engineer Rich Costey in this March 2008 Sound on Sound interview. An image of the settings for the intro vocal can be found here.

Very few plug-ins were used on the mix for 'The Pretender', but intro vocals were treated to Reel Tape Saturation and Pultec EQP1A, while a vocal overdub at the end of the track was processed with Sound Toys' Echoboy.

(...) Vocals: Mercury EQH, UA 175, Roger Mayer RM58, Waves DeEsser, Digidesign Reel Tape Saturation, Sound Toys Echoboy, Pultec EQP1A, SPL De-esser, Neve Portico 5042

"If I recall correctly, the lead vocal is doubled throughout the song. I used a Waves DeEsser plug-in on it, which I'm quite a fan of, as I've not heard a hardware de-esser that is competitive with it. The main signal chain after that was a Mercury EQH tube EQ and then a couple of vintage UA 175s. I hit the background vocals with the Roger Mayer RM58. I haven't mentioned any plug-ins yet, apart from the Waves DeEsser, because I hardly used them on 'The Pretender.' The only other ones I used were the Reel Tape Saturation and the Pultec EQP1A on the intro vocals, and the Sound Toys Echoboy on one of the end vocal overdubs.

"I used board EQ on all the vocals. The Pultec EQP1A plug-in on the intro vocals was to help them cut through. The Reel Tape Saturation was a plug-in that I had just bought. I wanted to warm the vocals up a little bit with it and make them a little bit crisper. Nothing too distorted. The Echoboy plug-in was used on a vocal overdub at the end for a tight delay. I don't tend to use plug-ins that much; they're really not that interesting, in my opinion. Finally, I also used an SPL De-esser on some vocals, and the Neve Designs Portico 5042 for a bit of crispness. It has its own sound, and I used it a lot on the whole Foo Fighters album.

"To complete the picture, I used an EMT plate and the room mics for general reverb, and my two EAR 660 limiters were my bus compressors, together with the Manley Massive Passive. We printed the mix to the ATR102, on half-inch analogue tape, from which it was mastered."

for vocals I use a lot of SoundToys stuff, the Decapitator or EchoBoy

This article on the making of Marr's 2018 Call the Comet album by MixOnline.com touches on some of the gear used during the recording process. "'We used some Lexicon PCM91 outboard reverb and some EchoBoy, not necessarily timed to the track so it could bounce around a bit and fill space,' says [engineer] Doviak." (While the engineer is providing this feedback, the gear is housed in Marr's own Crazy Face studios, which contains gear he's collected over his decades in the music industry.)

"Calling EchoBoy a delay plug-in is doing it a disservice. It has become the first thing I turn to for treating a wide variety of sources. An EXCELLENT sound / space shaping tool and the most flexible and musical delay out there"

At 1:43:33 in the Spotify episode titled "TN:153 Porter Robinson," Porter Robinson states that he prefers using the Soundtoys EchoBoy Analog Echo Processor over the default FL Studio plugin. He explains that the default plugin doubles the volume of the repeated note, especially when using digital sound, whereas EchoBoy offers a pitch modulation setting.

In this inteview, Steve Aoki gives us a look to the main gear he use to produce records in both of his studios : The ''Neon Future Cave'' in Las Vegas, NV and the ''Dim Mak Studio'' in Los Angeles, CA.

I have a good amount of Waves plugins, like the CLA Vocal and the JJP Vocals. I think that most people use those. These are all basically one vocal engine that includes compression, EQ Boost, Delays etc. Soundtoys is another plugin that I use, Echo Boys for delays, Crystalliser, which has some cool stuff with pitch shifting and reverse echo.

The EchoBoy plugin is used by Kaskade on vocal tracks.

in the video at 2:38 seconds where you see as well as hear them talk about using the EchoBoy on the track "Alone"

After being asked: "Is all of your processing/production work done inside Ableton Live?", he answered "There are a few third-party gizmos that I couldn't live without. The PSP Vintage Warmer is on everything; the SoundToys stuff goes well beyond anything you'd expect from a delay unit - it almost has a voice of its own; and CamelPhat is a versatile combined filter and overdrive - a very creative tool."

In a livestream on April 1, 2020, titled "Today's CoronaJam: A Hybrid Theory-style demo," Mike Shinoda uses the Soundtoys EchoBoy Analog Echo Processor.

Jacob showcases his use of EchoBoy in his 'All I Need' Logic Session Breakdown at 29:59 to add a subtle delay to his lead vocals. Jacob says that it lets his vocals "breath" and provide width, and talks about his interaction with Ben Bloomberg, who recommended him the plugin, when he says that Ben told him that "delay can be reverb".

Used on Lamar's vocals for "All the Stars" as stated by producer Matt Schaeffer in this May 2018 Sound on Sound interview.

Kendrick Lamar’s vocal audio tracks, named after his teenage stage name K.Dot, consist of his first verse rap track, ‘VS 1 LD’, and 10 tracks for three moments in the track where he sings the pre-hook in a robotic voice. The verse rap track only has the AIR Flanger on it, and is sent to the ‘Dot VS LD’ aux track, which has eight inserts and five sends. Nine of the 10 pre-hook tracks have Auto?Tune, while the top four have a number of plug-ins on the inserts, including the EQ3 seven-band, Waves RVox, UAD Galaxy Tape Echo, SoundToys Little AlterBoy, SoundToys MicroShift and Valhalla Vintage Verb. These four are sent to a ‘Hook Ref’ aux track higher up in the session with another four plug-ins on the inserts and five sends. The other six are backing vocals to the four other pre-hook tracks and have no other plug-ins, other than a Trim, and are sent to a ‘Hook Background’ aux, just below them, which itself also is sent to the ‘Hoof Ref’ track. It’s a pretty complicated vocal signal chain, as Schaeffer admits.

“The ‘Dot VS LD’ aux indeed has a lot of stuff on it! I did most of the processing on that bus. On the inserts there are the SSL E-Channel, Waves RComp, Waves Q10 EQ, Waves DeEsser, UAD LA2A, UAD Pultec EQP1A, SoundToys Decapitator and Pro?Q2. The SSL channel strip, Q10 and RCompressor remain from the tracking, and maybe the DeEsser as well, but I most likely messed with the settings more during mixing. The Q10 has a high-pass at 50Hz and I notched out a frequency that was bothering me around 8.5kHz with the Q2. I added the other plug-ins during mixing, and they all add something a bit different. I’m boosting 100Hz and 16kHz with the EQP1A. As I said, I like using several EQs on one thing.

“The sends go to a ‘FlangeVerb’ track, on which I put the RVerb and the UAD MXR Flanger, then the ‘Huge Verb’ with the [Audio Ease] Altiverb and EQ3, ‘Hook Valhalla’ with the Vintage Verb, and the SoundToys EchoBoy, the ‘EMT250’ aux with the UAD EMT250, Valhalla Plate and MicroShift, and then finally a send to the ‘Dot VS Delay’ track, with the EchoBoy, set to quarter note, the Reel Tape Flanger and the RCompressor. The EchoBoy is the main delay you can hear in the verse. The EMT250 is not set to a reverb, but to a phaser effect, which gives a cool stereo effect. The Valhalla adds a bit of reverb here, though it’s set to -12, so it only gives a tiny bit of ambience, and the MicroShift makes the whole thing a little wider. It probably still sounded a bit dry, which is why I sent the track to the ‘Huge Verb’ aux with the Altiverb, again taking out low end with the EQ3.

“In the pre-hook, Kendrick wanted that robotic sound with tons of effects. The main robotic effect comes from the iZotope VocalSynth, which gives it a vocoder-like sound. There also are some instances of the Little AlterBoy on the lead vocals in the pre-hook, with some formant adjusting and pitch-shifting. I think one of them is set to +12, so that’s an octave up, and another has a lower formant so it sounds pitched down, even though it remains in the same key. All that adds up to make the vocals sound robotic.”

Adding all inserts on audio and aux tracks together, Lamar’s verse rap is treated with a whopping 22 plug-ins! The ‘Hook Background’ aux, meanwhile, has the EQ3 seven-band, RCompressor, SoundToys Panman, a chorus, the MicroShift, the UAD MXR Flanger and the Valhalla Plate on the inserts and has sends to an aux track with the Waves Kramer Tape plug-in as well as the aforementioned ‘Hook Valhalla’ aux with the Vintage Verb, and Echoboy, and it then is routed to the ‘Hook Ref’ track, which has another four inserts and five sends. Phew.