Yeah ... this bothers me.
I'll say outright that I have a touch of an issue with "low distortion" thus far.
If I have to add things to get back the "body" of the midrange.....
Or if I have to feed these amps with $1500 power supplies, they are NO GOOD to me. Because at $3000 I have hundreds of better options, in MY opinion.
I just delivered a perfect pair of speakers, using the Purifi woofers. The owner is praying for break in change, because the bass is very strange. He's missing midbass, and has too much deep bass .... although the measurements are perfect.
Room and system are not issues, nor is speaker placement, as he's experimented.
I fear he's hearing a lack of distortion that doesn't seem "natural" ... time will tell.
Just my experiences so far
.. not an attack on Purifi!
If the "body" in the mid range is due to distortion, then it will have to be added in as Purifi is not going to add distortion. It is designed to play the input signal without adding or subtracting anything, only making it larger. If you aren't after high fidelity, you are barking up the wrong tree.
The other possibility, much more likely, is that there are issues with the room. How can the "measurements be perfect" and yet he is hearing differently? Have never seen a perfect room before...
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I disagree completely. If the body of the midrange is not right, it is FLAWED.
Live human voice has a presence and body. If the Purifi doesn't capture this, it fails.
So I guess every amplifier is flawed, and Purifi is "right".
I know what sounds like reality. I've only been to thousands of live music events. I'm a lifelong musician. The Purifi amps fell on their face in our listening tests.
Why are the BEL amplifiers considered so great? Neutrality and low distortion. Somehow they are not sucking out the life in the mids. They are Purifi amplifiers, designed 44 years ago. Same exact bragging traits. But the BEL sounds real.
The Purifi amplifier didn't.
I've compared both... have you?
You're welcome to come by anytime. Seriously, I'd love to have you. But don't come, unless prepared to be very disappointed in Purifi, once you found BEL does everything they're famous for, only better.
People continue speaking of the BEL amplifiers as adding color, and being another Class A/B amplifier... wrong. Dead neutral. But very full of life. Why do you think they're considered reference amplifiers that displace amps costing 10 times more?
BEL amplifiers are an anomaly in the business.
Live human voice has a presence and body. If the Purifi doesn't capture this, it fails.
So I guess every amplifier is flawed, and Purifi is "right".
I know what sounds like reality. I've only been to thousands of live music events. I'm a lifelong musician. The Purifi amps fell on their face in our listening tests.
Why are the BEL amplifiers considered so great? Neutrality and low distortion. Somehow they are not sucking out the life in the mids. They are Purifi amplifiers, designed 44 years ago. Same exact bragging traits. But the BEL sounds real.
The Purifi amplifier didn't.
I've compared both... have you?
You're welcome to come by anytime. Seriously, I'd love to have you. But don't come, unless prepared to be very disappointed in Purifi, once you found BEL does everything they're famous for, only better.
People continue speaking of the BEL amplifiers as adding color, and being another Class A/B amplifier... wrong. Dead neutral. But very full of life. Why do you think they're considered reference amplifiers that displace amps costing 10 times more?
BEL amplifiers are an anomaly in the business.
Not sure you'd be prepared to make the effort, but if you power the Bell off a suitable smps you might get surprised at how you have gained speed but lost body.
I'm sure all your listening "tests" were level matched, unsighted, right?
They can't be both dead neutral and yet "very full of life". Purifi puts out what is put in. A properly designed amp as stated earlier gives you exactly what you put in, with gain. Nothing added, nothing removed. By all objective criteria, that is what Purifi does. They don't have a "sound". No doubt you are heavily invested in your BEL amps, literally and figuratively as you mention driving 8 hours to buy yet another pair to add to the 11 or whatever you already have. That's fine. You like their distortion signature. Enjoy!
My BEL's distortion signature sounds just like real life. Richard tuned each one by hand to do this.
Thank God!!!
Thomas from YouTube needed a tube input buffer to get the best from his Purifi amp. He must have found the missing distortion needed. 😉
Thank God!!!
Thomas from YouTube needed a tube input buffer to get the best from his Purifi amp. He must have found the missing distortion needed. 😉
Hypex and Purifi modules shouldn't be driven from a floating source, and output impedance needs to be resistive 50 ohms, so a tube buffer will be problematic, and performance will be compromised.
IME, an ideal solution to drive Hypex / Purifi is a decent op-amp with discrete class A buffer. Also, ferrite beads or cable clamp-on's at the audio inputs on the Hypex / Purifi modules eliminates any unnatural brightness or harshness. My recent NCx500 mono builds sound sublime driving any speaker.
The very best amplifiers are still linear class A / AB but you really need to spend big bucks to best the best of class D these days.
IME, an ideal solution to drive Hypex / Purifi is a decent op-amp with discrete class A buffer. Also, ferrite beads or cable clamp-on's at the audio inputs on the Hypex / Purifi modules eliminates any unnatural brightness or harshness. My recent NCx500 mono builds sound sublime driving any speaker.
The very best amplifiers are still linear class A / AB but you really need to spend big bucks to best the best of class D these days.
@Flaxxer and others: https://pmamagazine.org/is-class-a-amplifier-design-stagnating/
To reflect on??
To reflect on??
Pardon my neophyte question, but what would be the best/simplest buffer to add a volume pot and make this an integrated amp? Thank you.
You could try to control the volume just before the input signal hits the buffer card (route the RCA/XLR wiring straight to the potentiometer; feed the wiper out to the buffer board input). This solution could be frequency and impedance dependent on the wiper position, hook-up wiring type/execution and output impedance characteristics of your source. However, it will work well, and you may be perfectly happy with the result. A bit of drilling and ensuring the actual volume pot positioning is right above the input buffer card will be needed.. to minimise the hook-up wiring lengths in what appears to be an extremely harsh environment... with SMPS/mains cabling spitting HF rubbish everywhere. So, some care is needed to execute this volume control properly.
The actual class D amplifier module input (sans buffer board) has severely reduced input impedance... so feeding the wiper-out to this module input (bypassing the buffer input board) would be unacceptable...
The actual class D amplifier module input (sans buffer board) has severely reduced input impedance... so feeding the wiper-out to this module input (bypassing the buffer input board) would be unacceptable...
It's slightly complicated by the balanced inputs so you'll need a 4-gang log potentiometer - such as ALPS etc.
Ghentaudio has cases for the most popular poweramps modules, a have a Purifi and it’s nice sounding. I have nothing to do with Ghent.
https://www.ghentaudio.com/
https://www.ghentaudio.com/
According to you.
Driving Hypex and Purify with tubes is succesfully done.
https://www.diyaudio.com/community/...urifi-1et400a-amps.379211/page-3#post-7046086
I am using for decades tube buffers for Hypex and purify modules. For me is this the best solution.
I use mu follower stage with feedback. Output impedance is about 25 ohm. Pure class A.
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