Buckeye Amps: Purifi 1ET6525SA (the successor to the 1ET400A)

[Buckeye Amps]

An update regarding the current tariff situation:

Unfortunately, due to the current 10% baseline tariff on all goods coming from the EU (which affects both our Hypex and Purifi components) we are finally forced to raise prices on all of our amps to offset. The price increase will not be severely drastic and, for most customers, should not affect the price vs. performance of our amplifier lineups.

This decision was not made lightly and is something I have been wrestling with for a few weeks. It might surprise most that we have not raised any of our amp prices for nearly 2yrs, even in the face of slight cost increases and inflation. But with our main components now affected, it is unavoidable.

Even with the price increases, I still believe we are poised as the audiophile for the masses brand we have always strived to be. And with this situation being fluid, prices can always come down if the current market situations change. We will also be exploring opportunities to lower prices in the present atmosphere, if possible, through higher purchasing power and/or manufacturing sources.

Thank you everyone!

 

[Stereoed]

Purifi 1ET6525SA Power Specs:
230w into 8ohm
450w into 4ohm
510w into 2ohm

Custom Input Buffer Board w/:
- Neutrik XLR connectors
- 5-way gold plated binding posts
- OPA1612 OP Amp
- TI TPS7A30/49 Voltage Regulators
- Low, Med, High Gain settings
- Clipping Indication (via Front Power LED)
- Error Indication (via Front Power LED)
- Muted Soft-start/shutdown (minimizes speaker “pop” when turning on and off)
- Auto On/Off (along with Always On and 12v options)

Gain settings:
4ohm - 25dB/2.2Vrms (High), 20dB/3.9Vrms (Medium), 15dB/6.9Vrms (Low)
8ohm - 25dB/2.3Vrms (High), 20dB/4.0Vrms (Medium), 15dB/7.1Vrms (Low)

1ET6525SA 2ch Amplifier:
(2) Purifi 1ETxxxxSA modules
(1) Hypex SMPS1200A400
10"x13"x3.5" Aluminum case

1ET6525SA 3ch Amplifier:
(3) Purifi 1ETxxxxSA modules
(1) Hypex SMPS1200A400
14"x14"x3.5" Aluminum case

*Rackmount case upgrade available

*Free US Shipping
*International shipping available

Email directly ([email protected]) for buying or if you have any questions at all

Visit our website for up to date specs, pricing, and pictures:
Buckeye Amps Official Site

Hi Dylan,
You wrote that your monoblocks with the Purifi 6525 module have a soft start and soft shutdown.
Is this a special feature of Buckeye Amps? Or is it built into the Purifi module?
I have the problem that my Hypex Nilai monoblocks make noise when turning on and off. It bothers me, and that's how I came across your post here in the forum. The Nilai monoblocks are connected to the Eversolo A8 via XLR and trigger. I've already asked Hypex itself, and they blame it on the Eversolo A8. In the meantime, however, I've found out that this problem is known with the Hypex Nilai, Hypex NCX500, and Purifi 7040. Now I'm thinking about buying the Purifi 6525, and of course I want to rule out the possibility that these Purifi 6525 modules also have this problem.

Thanks in advance

 

[Chesapeake HT]

Not sure what your Eversolo allows, but I have all external Buckeye amps (two Hypex based units) connected to my AVR (Denon x4700) and get slight “pops” through my speakers when they power on by triggers from my AVR. My solution was to set the initial volume upon power on at a fairly low volume. Still can hear a very slight pop, but much less. Cheers

 

[Stereoed]

Not sure what your Eversolo allows, but I have all external Buckeye amps (two Hypex based units) connected to my AVR (Denon x4700) and get slight “pops” through my speakers when they power on by triggers from my AVR. My solution was to set the initial volume upon power on at a fairly low volume. Still can hear a very slight pop, but much less. Cheers

What do you mean by "what my Eversolo allows"? I used a Yamaha AS 2200 as my power amp. The Eversolo A8 was also connected to the Yamaha via XLR and Cinch and trigger. I didn't hear any noise when turning it on or off.

I'm starting to think that these Class D power amps are simply cheaply constructed.

 

[Buckeye Amps]

I'm starting to think that these Class D power amps are simply cheaply constructed.

If you say so.

I can say it is heavily setup dependent. My Paradigm/Goldenear setup has no pop during start up or shut down. My Klipsch setup has slight pop, which isn't harmful to the speaker.

 

[Stereoed]

If you say so.

I can say it is heavily setup dependent. My Paradigm/Goldenear setup has no pop during start up or shut down. My Klipsch setup has slight pop, which isn't harmful to the speaker.

Hi Dylan,
You wrote that your monoblocks with the Purifi 6525 module have a soft start and soft shutdown.
Is this a special feature of Buckeye Amps? Or is it built into the Purifi module?
I have the problem that my Hypex Nilai monoblocks make noise when turning on and off. It bothers me, and that's how I came across your post here in the forum. The Nilai monoblocks are connected to the Eversolo A8 via XLR and trigger. I've already asked Hypex itself, and they blame it on the Eversolo A8. In the meantime, however, I've found out that this problem is known with the Hypex Nilai, Hypex NCX500, and Purifi 7040. Now I'm thinking about buying the Purifi 6525, and of course I want to rule out the possibility that these Purifi 6525 modules also have this problem.

Thanks in advance

 

[Buckeye Amps]

Hi Dylan,
You wrote that your monoblocks with the Purifi 6525 module have a soft start and soft shutdown.
Is this a special feature of Buckeye Amps? Or is it built into the Purifi module?
I have the problem that my Hypex Nilai monoblocks make noise when turning on and off. It bothers me, and that's how I came across your post here in the forum. The Nilai monoblocks are connected to the Eversolo A8 via XLR and trigger. I've already asked Hypex itself, and they blame it on the Eversolo A8. In the meantime, however, I've found out that this problem is known with the Hypex Nilai, Hypex NCX500, and Purifi 7040. Now I'm thinking about buying the Purifi 6525, and of course I want to rule out the possibility that these Purifi 6525 modules also have this problem.

Thanks in advance

It is a feature of the input board we use, so all of our amps have the function. But it is not a be all end all. As I said, the behavior is very setup dependent so chances are you may still have a slight pop sound even switching to a Purifi solution.

 

[Guddu]

It is a feature of the input board we use, so all of our amps have the function. But it is not a be all end all. As I said, the behavior is very setup dependent so chances are you may still have a slight pop sound even switching to a Purifi solution.

Hi Dylan,
Interesting you say 'ON/OFF pop' is dependent on the setup, I would think if the finished amplifier (not just the amplifier module) has it then its there always.
Highly sensitive speakers are more likely to make it much apparent (or a bit louder) while others a bit less.

 

[Buckeye Amps]

Hi Dylan,
Interesting you say 'ON/OFF pop' is dependent on the setup, I would think if the finished amplifier (not just the amplifier module) has it then its there always.
Highly sensitive speakers are more likely to make it much apparent (or a bit louder) while others a bit less.

I can only give the evidence I have based on testing and customer feedback. From those sources of data, there are a majority of users who report no sounds/pops during startup or shutdown.

Regarding speaker sensitivity, that would make sense but my JBL speakers were 101dB and had no pop sound at all.

 

[anotherhobby]

My setup with the 3 channel Purifi 6525 Buckeye amp also has a slight tick/pop when it comes on. It doesn't bug me in the least. It's being fed from a Denon AVR-X4800H, outputting to Philharmonic HT Towers/Center, and being powered on by 12v trigger. Overall, I couldn't be happier with this amp in my theater — it's a beast!

 

[Guddu]

So sehe ich das auch. Ich denke, es ist ein generelles Problem. Die Geräusche entstehen wahrscheinlich durch einen einfachen Konstruktionsfehler. Die Hypex-Netzteile brauchen zu lange, um sich zu stabilisieren. Oder es liegt am DC-Offset. Ich hatte vorher einen Yamaha AS 2200. Den habe ich als Endstufe und gleichzeitig als Vollverstärker an den Eversolo A8 angeschlossen. Ich habe ihn mit einem Cinch-Kabel direkt an den Haupteingang des Yamahas und dann mit einem XLR-Kabel an den Vorverstärkereingang des Yamahas angeschlossen. Beim Ein- und Ausschalten habe ich zu keinem Zeitpunkt Geräusche gemacht. Und der Yamaha hat ja bekanntlich ein sehr gutes Netzteil. Ich denke, es liegt am Hypex-Netzteil. Und ja, ich habe Lautsprecher mit einer Empfindlichkeit von 91 dB.

It does not have to be anymore complicated than a simple test to start with.
Simply connect speakers to amplifier, no source/pre-amp/DAC, and then test power ON/OFF pop. If it's there ON/OFF pop then its there from amplifier, if its not there then its not there.

 

[Stereoed]

Es muss nicht komplizierter sein als ein einfacher Test für den Anfang.
Schließen Sie die Lautsprecher einfach an den Verstärker an (keine Quelle/Vorverstärker/DAC) und testen Sie dann das Ein-/Ausschalten. Wenn es ein Ein-/Ausschalten-Knackgeräusch gibt, liegt es am Verstärker, wenn nicht, liegt es nicht daran.

Yes. That is what I made too. The same problem.

 

[Buckeye Amps]

Just a reminder to please post replies in English. Thank you!

 

[Stereoed]

Just a reminder to please post replies in English. Thank you!

Yesss. Sir. BTW. If I as a German can use a translator. YOU as an American sound be able too. Sorry.

 

[Buckeye Amps]

Yesss. Sir. BTW. If I as a German can use a translator. YOU as an American sound be able too. Sorry.

It's not me trying to be difficult, it's the forum rules.

 

[Stereoed]

It's not me trying to be difficult, it's the forum rules.

Dylan. It was an oversight. I was editing from my translation program. Sorry. But I think that's the end of it for me with Purifi and Hypex. I consider them to be faulty designs. Probably not because it can't be done, but because it would be too costly to solve the problem properly. And that would make these products too expensive. Or why doesn't Yamaha have this problem?

 

[Buckeye Amps]

Dylan. It was an oversight. I was editing from my translation program. Sorry. But I think that's the end of it for me with Purifi and Hypex. I consider them to be faulty designs. Probably not because it can't be done, but because it would be too costly to solve the problem properly. And that would make these products too expensive. Or why doesn't Yamaha have this problem?

That's your choice obviously.

 

[RickS]

Dylan. It was an oversight. I was editing from my translation program. Sorry. But I think that's the end of it for me with Purifi and Hypex. I consider them to be faulty designs. Probably not because it can't be done, but because it would be too costly to solve the problem properly. And that would make these products too expensive. Or why doesn't Yamaha have this problem?

The Yamaha is an integrated amplifier and likely the inputs are not dc-coupled. Power amplifiers tend to be dc-coupled. Have you measured for dc in your system? DC offset can make the problem worse. Some of the older Hypex MP series had some uglier power up behavior, but they have improved.

I have a Purifi EVAL1 connected to SPK4 speakers (with expensive Mundorf AMT). It is powers via an Alexa-controlled power strip and get a slight click at power up. If your problem is DC, not likely to damage a passive speaker in any case. If you cannot measure for DC, do you have a preamp?

 

[tmtomh]

Before I switched to active speakers, I used a Purifi-based amp. It used 2x of the previous 400ET modules (and just FYI it was from Audiophonics). It had zero power-off noise. On power on, a momentary low-level sound would come out of my speakers. I would best describe it as a "tick" sound - like a click but shorter in duration, very low in volume, and without the high-frequency transient "snap" or "edge" that I associate with a click sound. I emailed Audiophonics about it, to see if that was normal. They said Yes.

Now with my actives (Genelec 8351b's), when I turn them on and off I hear what I would describe as an even more muted version of that tick sound. It's sufficiently low in level that if I'm not paying attention I don't always hear it and have to walk up to the speakers to confirm that they're turned on (or off, as the case may be).

I get that different modules, designs, units, and so on have different levels of turn-on and/or turn-off sounds. But unless it's fairly loud, I have trouble understanding how it could be considered a design fault. I've had A/B amps that made popping sounds turning on, or that made a sort of low-level "squelching" sound when turning off (I assume from capacitor discharge and no power-off mute). I was never concerned about it - that's just the way some designs are, yes?

 

[thegeton]

"...A/B amps that made popping sounds turning on, or that made a sort of low-level "squelching" sound when turning off..."

I'm the original owner of an Adcom GFA-555 that has done a bit of both all of its life, almost 39 years. Still works like a champ.