Buckeye 3 Channel Purifi Amplifier Review (2nd)

[mrstark]

I'm curious, are the power vs distortion charts in the review indicative of continuous power?

 

[Pareto Pragmatic]

What's to say about my new 2 channel version, other than "price to performance" and "measurements"? A couple small things.

First, price and performance got this on my list, but what sold me was their warranty page. Not the warranty (which is good), but the page. After reading that, I decided this is the kind of company I would like to do business with.

Second, there was a delay in my order due to a supply order being split. I found communication on this to be top notch, I could expect no better. That includes a prompt response and an unsolicited follow up, both times giving me a "hope to ship by" date. I had the amp by the hope to ship by date.

Third, the connectors (discussed up thread). They make a noise when engaged and are quite secure. When would I want fully locking connectors? Live performance, studio, where accidental failure is more likely and more costly than in a home environment. But I do understand why people might like fully locking over spring locking, I'm just not one of those people.

Fourth, I do like 3 gain stages for current and future flexibility. Better than one or two!

As for the performance? I've never had an amp this accurate before, so... My first reaction was "Wow, the bass!". Second, "this reminds me of headphones" because it was dead quiet. Third, great separation in the sound stage. Everything else was better too, but those were the biggest difference between this and the fosi v3 it replaced.

This amp fit my needs, and the company was good to deal with. The price was right, the performance as the measurements would lead me to expect. So a good deal, and a good company to work with.

 

[PHD]

I know that it shouldn't make any difference because it measures almost perfect, but I wonder why the standard PSU cable isn't twisted and/or shielded?

This really bugs people with OCD like myself...

 

[Matias]

Since it is plugged I guess you can unplug it, twist it, and plug it back, no?

 

[amper42]

I know that it shouldn't make any difference because it measures almost perfect, but I wonder why the standard PSU cable isn't twisted and/or shielded?

View attachment 392689


This really bugs people with OCD like myself...

Boxem offers nice shielded cabling with the Arthur 4215/E2 build and quality ETI binding posts.

 

[Buckeye Amps]

The question answered itself, however. Sure it looks nice, but in terms of an measurable, let alone audible, difference...

 

[PHD]

Boxem offers nice shielded cabling with the Arthur 4215/E2 build and quality ETI binding posts.
View attachment 392692

You can't tell if it is twisted and that's doesn't look like a (gounded) shield. It looks like just a braided tubing to make it look nice.

 

[Descartes]

Boxem

Aren’t they more expensive than Buckeye?

 

[amper42]

Aren’t they more expensive than Buckeye?

When I was shopping for another Purifi amp I was looking for quality binding posts like the ETI posts on my March Audio P452. I asked Buckeye if I could pay more for better binding posts. He was unable to accommodate the request so I asked Boxem if they could install ETI Kyro binding posts on their Arthur 4215/E2. Boxem was happy to help. I also wanted the higher gain options offered by Boxem on the 4215/E2. It's nice to be able to find a build with 27dB gain which matches AVR setups a bit better. I also noticed the build inside looked more professional than my Buckeye amps.

To your question, the Boxem ended up costing me $350 more than a Buckeye Purifi but the case was so much nicer, it included the ETI Kyro binding posts and support for higher gain options I wanted. The Boxem build quality is amazing. It was just what I wanted and the few extra dollars were well worth it for me. It's nice to have several sources for Purifi amps so users can get the options they desire.

 

[Buckeye Amps]

Definitely nicer looking options out there than our boring cases, have never argued that. And if people want to pay more money for looks (for both the case and binding posts), all the power to them.

 

[Descartes]

When I was shopping for another Purifi amp I was looking for quality binding posts like the ETI posts on my March Audio P452. I asked Buckeye if I could pay more for better binding posts. He was unable to accommodate the request so I asked Boxem if they could install ETI Kyro binding posts on their Arthur 4215/E2. Boxem was happy to help. I also wanted the higher gain options offered by Boxem on the 4215/E2. It's nice to be able to find a build with 27dB gain which matches AVR setups a bit better. I also noticed the build inside looked more professional than my Buckeye amps.

To your question, the Boxem ended up costing me $350 more than a Buckeye Purifi but the case was so much nicer, it included the ETI Kyro binding posts and support for higher gain options I wanted. The Boxem build quality is amazing. It was just what I wanted and the few extra dollars were well worth it for me. It's nice to have several sources for Purifi amps so users can get the options they desire.

True I agree especially when amplifiers are out in a living room. I personally like the design from Apollon Audio, Nord and NAD.

Of course they are more expensive!

One moment, please...

Nord Three 1ET7040SA 3CH MKII 3 Channel Power Amplifier - Nord Acoustics Ltd

The Nord Three 3CH MKII is our upgraded Purifi EIGENTAKT 1ET7040SA 3CH amplifier using 3 x power supply. Consisting of amp module, PSU, Input buffer.

nordacoustics.co.uk

M23 - NAD Electronics

Building on NAD’s long tradition of identifying and developing cutting-edge amplification technology, the M23 HybridDigital Stereo Power Amplifier features Purifi Audio’s Eigentakt™ design, a once-in-a-decade innovation that virtually eliminates harmonic and intermodulation distortion. Noise is...

nadelectronics.com

 

[PHD]

I remember that in the first review, the SINAD was lower and it turned out that it was due to bad XLR connectors. How is that even possible? The only way I can think of is added intermittent noise due to loose contact but it should only occur transiently when the cables are moved, not reflect in the steady state measurements.

Also, at the Buckeye amp FAQ it says that RCA to XLR adapters are not recommended and whole cables are preferred for the same reason. Can someone elaborate on that because it kinda contradicts what this forum claims about the fact that cables don't really matter and yet a simple connector in the signal chain could reduce SINAD by 20dB?

Thanks

 

[amper42]

I remember that in the first review, the SINAD was lower and it turned out that it was due to bad XLR connectors. How is that even possible? The only way I can think of is added intermittent noise due to loose contact but it should only occur transiently when the cables are moved, not reflect in the steady state measurements.

Also, at the Buckeye amp FAQ it says that RCA to XLR adapters are not recommended and whole cables are preferred for the same reason. Can someone elaborate on that because it kinda contradicts what this forum claims about the fact that cables don't really matter and yet a simple connector in the signal chain could reduce SINAD by 20dB?

Thanks

Actually, XLR connectors had nothing to do with lower measurements on the original Buckeye Purifi design. The cause was steel hardware feeding the binding posts. The fix was to upgrade the parts to brass.

It's best to stay with XLR to XLR if possible. If not, using the proper XLR to Single ended cable will work. Using an adapter simply adds another point for failure and should be avoided.

 

[Buckeye Amps]

I remember that in the first review, the SINAD was lower and it turned out that it was due to bad XLR connectors. How is that even possible? The only way I can think of is added intermittent noise due to loose contact but it should only occur transiently when the cables are moved, not reflect in the steady state measurements.

Also, at the Buckeye amp FAQ it says that RCA to XLR adapters are not recommended and whole cables are preferred for the same reason. Can someone elaborate on that because it kinda contradicts what this forum claims about the fact that cables don't really matter and yet a simple connector in the signal chain could reduce SINAD by 20dB?

Thanks

It was the binding posts, not XLR connectors.
The original binding posts were ferrous, causing slightly higher distortion. That was rectified quickly. And have since switched to even higher quality binding posts.

But even then, there was no audible issue. Only measured.

 

[amper42]

It was the binding posts, not XLR connectors.
The original binding posts were ferrous, causing slightly higher distortion. That was rectified quickly. And have since switched to even higher quality binding posts.

But even then, there was no audible issue. Only measured.

Dylan,
What is the brand and model of the new binding posts currently installed on new Buckeye amps? Is it the same binding post on all Buckeye amps sold? What material are they made of? Are they magnetic? Thank you!

 

[Buckeye Amps]

Dylan,
What is the brand and model of the new binding posts currently installed on new Buckeye amps? Is it the same binding post on all Buckeye amps sold? What material are they made of? Are they magnetic? Thank you!

They are custom manufactured so no big brand name. Same on all amps/models. Brass (non magnetic)

 

[paulcc]

I think you meant to say "Brass (non magnetic)"

 

[PHD]

It was the binding posts, not XLR connectors.
The original binding posts were ferrous, causing slightly higher distortion. That was rectified quickly. And have since switched to even higher quality binding posts.

I assume that ferrous binding posts combined with the high-frequency PWM currents of the class D amp leads to induced eddy currents which can caused added HF noise ... Interesting. So what about the fact that 90% of speaker binding posts do contain ferromagnetic materials, even high-end Focals where proven to be ferromagnetic... Don't see the point in using non-magnetic posts on the amp side...

 

[Buckeye Amps]

I think you meant to say "Brass (non magnetic)"

Thanks. Auto correct issues apparently

 

[Buckeye Amps]

@PHD

That's why I mentioned the measurement difference noticed with the original ferrous binding posts was an inaudible issue and more just something to fix so measurements were in-line with what the Purifi 1ET400A should messure as.