Purifi EVAL1 EIGENTAKT Class D Amp Designs

[Andykay]

I'm m looking for persons who have purchased the Purifi EVAL1 EIGENTAKT based systems and any build mods. I'm looking for a Canadian Supplier with track record. I live in Canada and have only found VTV so far.

I'm planning on using a VTV Purifi type amplifier as a front left and right Channel amplifier connected via XLR to a Yamaha 3080 AVR.

FYI, the Purifi EVAL1 EIGENTAKT setup is now shipping in the NAD C298 (similar to NAD M33 in theory) with what looks like a custom buffer power supply. I have only seen pics and have not done a teardown with one yet. It's price is $2,899.00 CAN which seems steep for NAD stuff.

Please share your experiences.

 

[Phorize]

I'm m looking for persons who have purchased the Purifi EVAL1 EIGENTAKT based systems and any build mods. I'm looking for a Canadian Supplier with track record. I live in Canada and have only found VTV so far.

I'm planning on using a VTV Purifi type amplifier as a front left and right Channel amplifier connected via XLR to a Yamaha 3080 AVR.

FYI, the Purifi EVAL1 EIGENTAKT setup is now shipping in the NAD C298 (similar to NAD M33 in theory) with what looks like a custom buffer power supply. I have only seen pics and have not done a teardown with one yet. It's price is $2,899.00 CAN which seems steep for NAD stuff.

Please share your experiences.

I’m not sure about built systems but. @tomchr sells a good buffer stage if you were thinking diy. He may be able to give you a steer on what his other customers are doing.

 

[tomchr]

I’m not sure about built systems but. @tomchr sells a good buffer stage if you were thinking diy. He may be able to give you a steer on what his other customers are doing.

I'm happy to build amps. I should probably figure out the pricing...

Tom

 

[Madjalapeno]

I'm happy to build amps. I should probably figure out the pricing...

Careful, they're addictive.

You buy two of his amps, and suddenly you're thinking how you need more speakers so you can get more of his amps!

 

[phoenixdogfan]

I'm happy to build amps. I should probably figure out the pricing...

Tom

Would probably be the ultimate Purifi Eigentact build.

 

[Andykay]

I’m not sure about built systems but. @tomchr sells a good buffer stage if you were thinking diy. He may be able to give you a steer on what his other customers are doing.

Thank you very much

 

[dwkdnvr]

I'm happy to build amps. I should probably figure out the pricing...

Tom

That might be interesting.

I'm currently sitting here wondering whether I should feel guilty about considering replacing my Mod-86 with a VTV Purifi and then adding Neurochrome buffers.....

 

[pogo]

This seems to be the best sounding implementation at the moment:
Link

A big advantage is the switchable damping factor!

 

[boXem]

This seems to be the best sounding implementation at the moment:
Link

Why would it be better sounding than other implementations?

A big advantage is the switchable damping factor!

That's indeed an interesting differentiator. I just don't get the point of lowering the damping factor. Could you please explain?

 

[tifune]

A big advantage is the switchable damping factor!

That's interesting, I sort of dismissed damping factor years ago after reading this (which Im not qualified to confirm or refute)

Damping Factor: Effects On System Response

Much ballyhoo surrounds the concept of "damping factor." It's been suggested that it accounts for the alleged "dramatic differences" in sound between tube and solid state amplifiers. The claim is

www.audioholics.com

is it worth reconsidering?

 

[Matias]

I just don't get the point of lowering the damping factor. Could you please explain?

Probably the user can tweak the speaker response somewhat.

SUMMER MUSINGS: No... Not all amplifiers sound the same (but many do! ;-).

A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.

archimago.blogspot.com

 

[boXem]

Probably the user can tweak the speaker response somewhat.

SUMMER MUSINGS: No... Not all amplifiers sound the same (but many do! ;-).

A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.

archimago.blogspot.com

If tweaking means "make a change without getting any idea of what will happen", yep

 

[pogo]

Why would it be better sounding than other implementations?

That's indeed an interesting differentiator. I just don't get the point of lowering the damping factor. Could you please explain?

I have written that it seems so. According to the test report, the T+A scored more sound points than the NAD C298.

'A high damping factor tends to produce a more clearly defined, very precise and analytical sound image, whereas a reduced damping factor produces a more warm and softer sound image.' <- extract from the manual

@Bruno Putzeys
What are the advantages of this new implementation of the purifi modules?

 

[pogo]

is it worth reconsidering?

Definitely, but it depends on the speakers you use or your own taste. My speakers need a high DF, otherwise my low frequency range sounds spongy and my room modes are unnecessarily excited, meaning I have to correct less with a DSP and sound details are also preserved.
Conversely, speakers with deficits in the low frequency range can be subjectively improved with a low DF.

 

[boXem]

I have written that it seems so. According to the test report, the T+A scored more sound points than the NAD C298.

My own implementation of the Purifi modules was recently subjectively reviewed against two other amplifiers using different technologies, but also at different price points.
Very well written and documented, several pages, all sort of musics listened, nice to read.
Summary in half a line: the most expensive sounds the best, the least expensive sounds the worst. Bad luck for me, my amplifier was the least expensive . What was particularly hard to swallow was that I consider one of the two other amplifiers as "$hit packed in golden paper" and it was supposed to sound better.

 

[pogo]

Very well written and documented, several pages, all sort of musics listened, nice to read.

Where to find this?

 

[peng]

I still like my VTV Purifi amp a lot but also still don't like the banana plug receptacles and speakon connectors instead of the typical binding posts. Actually I may like speakon, as I have never used them before. Can someone suggest speakeron to banana plug (speaker side obviously that will work well with the Eigentakt Eval1 amp? I have been searching it on Amazon, and see there are different kinds of speakon connectors.

Almost bought this one:

When reading the reviews, someone said its a 4 point contact type (instead of 2) and I am not sure if that is the best for my amp.

 

[BlackTalon]

I cut the banana plus off one end of the speaker cables and replaced with speak on connectors. Super easy. the wires get clamped in the connector by screws. All you need is snips that can cut through the cable, wire strippers and a screwdriver. 15 minute project the first time.

 

[tomchr]

I think the confusion is about the 2-pole vs the 4-pole type of speakON.

A 2-pole connector, such as the Neutrik NL2FX, makes two connections. One for Speaker+ (1+) and another for Speaker- (1-).
A 4-pole connector (Neutrik NL4FX) makes four connections: 1+, 1-, 2+, and 2-. This means you can use one cable to power two speakers or you can use one cable to power tweeter+woofer in a two-way bi-wired speaker.

The two-pole NL2FX will mate with a 4-pole chassis connector, but only make connections to two connections (1+ and 1-). I don't know if a 4-pole cable connector (NL4FX) will mate with a 2-pole chassis connector. One could ask Neutrik.

As mentioned above, I'd just buy the cable connectors and make the cables myself. It's pretty easy. Just follow the instructions on the package for how to strip the wire and you'll be fine. The connectors are available through Mouser: www.mouser.com and others.
Another trick I use if I need a speakON-to-wire end cable is to buy a speakON cable and cut it in half. GLS makes some quite nice cables. The cable is typically 12-14 AWG stranded with a flexible rubber jacket. It's nice to work with. The connectors are by Neutrik. You can buy from GLS directly or find them at Bezos' Bookstore.

BTW: I wouldn't bother with adapters. The point of this exercise is to get rid of the banana plugs.

Tom

 

[peng]

I think the confusion is about the 2-pole vs the 4-pole type of speakON.

A 2-pole connector, such as the Neutrik NL2FX, makes two connections. One for Speaker+ (1+) and another for Speaker- (1-).
A 4-pole connector (Neutrik NL4FX) makes four connections: 1+, 1-, 2+, and 2-. This means you can use one cable to power two speakers or you can use one cable to power tweeter+woofer in a two-way bi-wired speaker.

The two-pole NL2FX will mate with a 4-pole chassis connector, but only make connections to two connections (1+ and 1-). I don't know if a 4-pole cable connector (NL4FX) will mate with a 2-pole chassis connector. One could ask Neutrik.

As mentioned above, I'd just buy the cable connectors and make the cables myself. It's pretty easy. Just follow the instructions on the package for how to strip the wire and you'll be fine. The connectors are available through Mouser: www.mouser.com and others.
Another trick I use if I need a speakON-to-wire end cable is to buy a speakON cable and cut it in half. GLS makes some quite nice cables. The cable is typically 12-14 AWG stranded with a flexible rubber jacket. It's nice to work with. The connectors are by Neutrik. You can buy from GLS directly or find them at Bezos' Bookstore.

BTW: I wouldn't bother with adapters. The point of this exercise is to get rid of the banana plugs.

Tom

Yes the 2-pole vs 4-pole confused me. Thank you for explaining the difference, so since my Purifi amp is a typical stereo amp the connectors must be 2- pole. Unfortunately Amazon.ca don't sell any 2-pole ones, all the connectors I could find are the 4-pole type, some even says "female". I wonder why Purifi would supply this Eigentakt kit thing with professional connectors instead of the regular binding posts.

Monoprice has one that looks like it would work but it does not have the NL2FX, instead it has the NL4FC, but they are on a 2-conductor cable??

Monoprice 108769 10-Feet 12AWG 2-conductor Speakon Type NL4FC Female-Inch Speakon Type NL4FC Female Cable : Amazon.ca: Electronics

Monoprice 108769 10-Feet 12AWG 2-conductor Speakon Type NL4FC Female-Inch Speakon Type NL4FC Female Cable : Amazon.ca: Electronics

www.amazon.ca

Monoprice 108769 10-Feet 12AWG 2-conductor Speakon Type NL4FC Female-Inch Speakon Type NL4FC Female Cable​

3 Foot Speakon (Neutrik NL2FX) to Speakon (Neutrik NL2FX) Professional Speaker Cable 14AWG by Custom Cable Connection : Amazon.ca: Musical Instruments, Stage & Studio

3 Foot Speakon (Neutrik NL2FX) to Speakon (Neutrik NL2FX) Professional Speaker Cable 14AWG by Custom Cable Connection : Amazon.ca: Musical Instruments, Stage & Studio

www.amazon.ca

The one that has the number you mentioned is only 14 AWG but I guess I have to buy reluctantly, and use your nice trick of cutting it in half.

Do you think it will mate with the Purifi Eigentakt Eval1?

Thank you very much for your help.