Buckeye 3 Channel Purifi Amp Review

[IRG]

Monoprice makes adapters XLR>RCA that work well. Consider the Schitt preamps, the Freya+, Saga, etc. Not sure what you mean when mentioning "the current issue of the Purifi" unless you're referring to the 252 doesn't have the custom buffer?

What I meant about the current issue, is that the 3 channel amp tested here, the Purifi model, Buckeye mentioned that this affects all of their current Purifi amps, but not the Hypex models, I believe that’s what was mentioned. Apologies if I’m misremembering the details here.

Thanks for mentioning the cable from Monoprice, didn’t realize this was an option.

 

[IRG]

And yes the Freda S could be a good choice, no tone controls though but otherwise a good value for sure. Suppose I could add the Loki+ as well.

 

[Bachemar]

Just read this whole thread, phew. As someone who’s not an engineer or all that technically inclined, I do have some basic questions and maybe they are covered elsewhere. First off, I actually like the looks of these Buckeye amps. I hadn’t heard of them before but having the founder/ceo involved here, and describing the issue and how it will be fixed, gives me some sense of assurance. I tend to focus on name brands that have long(er) history; Yamaha, Marantz, NAD, Rega, etc. and most of these focus on class AB amps, with NAD moving to class D. I have no bias against a class D amp, never owned one but would like to try one. Actually my Fender Rumble bass amp is class D and works well, and is super light. But right above it is a little 5w Fender Vibro Champ Reverb tube amp which sounds great, and my other (guitar) amp is in neither camp, but is a solid state Roland BLues Cube Artists 80w (attenuated down to 1/2 w) but I digress with the guitar amp talk, only to say, I have spent large amounts of $ to add distortion that is pleasing to my ears, lol. Different purposes I know,

So I have two really basic questions for Buckeye (or others). I am a 2 channel guy, and am fairly set in some of my analog ways. I buy and enjoy vinyl still, also have and still buy CD’s, and use Spotify on my phone but will move into more streaming options soon when I move my audio system from a little man cave I have in the basement, into the main living room. So space and size of components is a consideration for me.

1) Difference between the Purifi 1ET400A 2 channel amp and the HypexNC252MP, besides price, the Purifi is rated with more watts but I don’t get hung up about that too much, either should be able to power whatever speakers I end up with. I understand the Hypex amp doesn’t have the current issue of the Purifi, so tonally, what are the differences if any?
2) both amps have only XLR outputs, which won’t work with my current integrated amp (Musical Fidelity M2Si) which has only RCA preamp outs. I’m thinking of moving on from this amp anyway, although it has served me well (power amp section not reviewed well by Amir), so I’d need a new preamp, one with XLR inputs for the amp, and I want tone controls (just personal preference). And I need the preamp to have analog connections,mlooking at a Vincent offering, but I believe it’s a hybrid, with some tubes in it, but maybe there are other preamps I should look at.

So that’s where I’m at, I like what I see from this amp, I like that it’s in the US, like that the issue (which doesn’t seem to have sonic issues) is being resolved, just curious how this might work in my analog 2 channel system. Sorry for lack of brevity.

You can use Monoprice RCa to XLR cables. The Buckeye is expecting a higher voltage on the XLR input, so the output of the Buckeye with an RCA (1V) input will likely be around 4 dB lower than your existing amp, assuming it was designed for RCA inputs. This means you need to turn up the volume a little more on your pre amp - Usually it’s not an issue, but if you were close to max volume, you could end up clipping on your preamp.

If you have a sub in the mix, you need to level adjust for the new gain and timing differences


Others can correct me on the specifics of the voltages and gain structure etc.

 

[Espiritiv]

More of a layout constraint for now....and the cost of bringing it to market. Both of which I planned on addressing sometime this year to get up to a 5ch Purifi.
But obviously all attention is on a fix, first.

It should fit a 5CH in a Rack mount case correct? Ill be your first Guinea pig when it comes time

 

[Buckeye Amps]

It should fit a 5CH in a Rack mount case correct? Ill be your first Guinea pig when it comes time

Yes, there shouldn't be any issue fitting 5ch in a rackmount or 17" wide case.

Obviously won't be starting any new protoypes until the current distortion is fixed.

 

[droid2000]

@Buckeye Amps i ordered a purify amp several weeks ago. Are you sticking with estimated shipping dates? Or are you holding off on shipments until you figure out the cause of the distortion?

 

[Buckeye Amps]

@Buckeye Amps i ordered a purify amp several weeks ago. Are you sticking with estimated shipping dates? Or are you holding off on shipments until you figure out the cause of the distortion?

Sticking with estimated ship dates unless the customer requests holding off

 

[droid2000]

Sticking with estimated ship dates unless the customer requests holding I don't see any reason to hold the shipment. Very excited to receive this amp.

Great. Thank you. Very excited to receive this amp.

 

[squared80]

Any updates on finding the issue?

 

[Buckeye Amps]

Any updates on finding the issue?

Waiting on delivery of a few components to check a couple more variables.

 

[Buckeye Amps]

Update:

We have measured a good amount of variables and scenarios. All of the preliminary data we have points to the distortion rise NOT stemming from our input buffer board.

But I am not declaring this as fact. We are sending off a few different test setups to a secondary party for them to measure and make sure they are seeing what we see, to rule out our test bench as a contributing variable.

Again, not at all saying "this is not our fault" and washing our hands of it. The opposite. We are leaving no stone unturned but as you can see it is taking some time.

 

[squared80]

Update:

We have measured a good amount of variables and scenarios. All of the preliminary data we have points to the distortion rise NOT stemming from our input buffer board.

But I am not declaring this as fact. We are sending off a few different test setups to a secondary party for them to measure and make sure they are seeing what we see, to rule out our test bench as a contributing variable.

Again, not at all saying "this is not our fault" and washing our hands of it. The opposite. We are leaving no stone unturned but as you can see it is taking some time.

Appreciate the update.

 

[Audiomn]

Update:

We have measured a good amount of variables and scenarios. All of the preliminary data we have points to the distortion rise NOT stemming from our input buffer board.

But I am not declaring this as fact. We are sending off a few different test setups to a secondary party for them to measure and make sure they are seeing what we see, to rule out our test bench as a contributing variable.

Again, not at all saying "this is not our fault" and washing our hands of it. The opposite. We are leaving no stone unturned but as you can see it is taking some time.

Would it make sense to have Amir test another one? Maybe the first one had something defective.

 

[Buckeye Amps]

Would it make sense to have Amir test another one? Maybe the first one had something defective.

(Don't take this as me sounding harsh or dismissive)

Amir should definitely not be used as a test bench in terms of a possible problem. Since we were able to replicate the distortion on our end/test bench setup, it would not be beneficial to either Amir or myself to send anything to him until it is ready.

 

[Audiomn]

(Don't take this as me sounding harsh or dismissive)

Amir should definitely not be used as a test bench in terms of a possible problem. Since we were able to replicate the distortion on our end/test bench setup, it would not be beneficial to either Amir or myself to send anything to him until it is ready.

Ah, I didn’t realize that you replicated the distortion. Makes sense.

 

[OldFart]

Change of subject but related to review.
Question for those who know more than me. I have a Adcom rated at 200 watts (8 ohms) per channel RMS amp driving my old 4 ohm MK 100Bs.
The spec on the Buckeye amp states 225 watts per channel at 8 ohms, but the review states 156 watts at 8 ohms.

Would I be loosing power and/or dynamic range replacing my old Adcom 555II amp with the Buckeye Purifi 1ET400A 2 channel amp?

I don't understand the power rating compared to the review. Thank you in advance....

 

[charlielaub]

There is some interpretation to the power ratings and how to define "max power". Typically this is when the distortion level at some high power level increases to some predefined level such as 1 percent. 1 percent is the same as -40dB. When you look at the distortion measurement from the review below (continued):

... you can see that -40dB is reached for a power level of about 200 W. The distortion starts to climb at the lower power level of 156W but there the distortion level is only circa -87dB or 0.005%. Some amplifers NEVER reach that for any power level, and I have wondered why this is assigned the "max power" level by Amir in other reviews as well.

There is an old GFA-555 II review with good measurements you can compare to here:

ADCOM GFA-555 II Review

There is a lot of good info contained therein. A plot of distortion vs power shows that the distortion level of the Adcom stays pretty low and constant at about 0.0005% at below 1W to about 0.0015% above 1W until turning up at 100W. This was when "new", and this is getting long in the tooth at this point and some component aging has likely occurred. Your amp may be performing much worse than this but you wouldn't know unless there was a major failure somewhere. The ear is just not all that sensitive to distortion.

What the Adcom amplifier (if it is actually performing up to original specs, likely not due to age and some PS cap degradation) offers is some headroom above the max power spec, for brief transients and with elevated distortion. The review lists that a power level of 265W was obtained with 0.68% THD (still not at 1 percent!).

IMHO overall the Buckeye amp's performance will be superior in terms of distortion at pretty much any power level up to about 100W, is brand new, running at spec (minus the current bug that is being worked out), and has a lower noise floor. The GFA-555 II is a very well regarded amp, but at this time you would be getting better performance out of the new Buckeye amp. I do not think you will miss the last 50 Watts or so, that is only 1dB or so difference at 200W and unless you are listening so that your ears bleed you will never reach these power levels except on transients.

It's possible to get the Adcom completely overhauled, with PS caps checked and lots of other components replaced and updated. This is another option you might consider. It's a very good amp when working well and up to spec.

The other option that I have to bring up, and one that might make a much bigger difference overall, is to upgrade those M&K speakers. I auditioned them IIRC in the late 1990s against a pair of Snell K-IIs that I owned and I was shocked how much worse the M&Ks sounded at the time. If you want to upgrade your "sound" you might start there and not with the amplifier. Lots of good commercial speakers under $2k these days. Just my unsolicited 2 cents. Take it or leave it.

 

[Klipshaholic]

Been reading a lot about the purifi amps and have always had my eye on the buckeye 3 channel amp. I currently have a monster power mpa 3250 amp and has been great sounding. Been looking to get a smaller footprint amp. Would I regret going to purifi from a class a/b that has more power?

 

[muslhead]

Been reading a lot about the purifi amps and have always had my eye on the buckeye 3 channel amp. I currently have a monster power mpa 3250 amp and has been great sounding. Been looking to get a smaller footprint amp. Would I regret going to purifi from a class a/b that has more power?

Only you can determine if you would regret it.
I wouldnt and am glad (for many reasons) i did it.

 

[Klipshaholic]

Only you can determine if you would regret it.
I wouldnt and am glad (for many reasons) i did it.

What kind of amp did you have before? And what changes made you not regret it? I had crown xls 2502 before so I like the efficiency but they were noisy.