Peachtree GaN 1 Beta

@yyzsantabarbara Just make sure you order the Digital version of it. The other two versions won't hook up to the GaN 1.

@donnylovely Thanks I think this is likely what I need,

The miniDSP Flex has many applications including as a compact digital stereo preamp, subwoofer integration and optimization to active speakers, home theater and recording studio implementations. 

miniDSP Flex (deercreekaudio.com)

@yyzsantabarbara You can use the speaker-level inputs on that sub. You could hook up your tuner to it with the Minidsp Flex Digital ($500) which will give you a ton of other options as well. You could even use your current preamp with the Minidsp Flex Digital and run your sub off the preamp still.

I am thinking of using the GAN1 amp in my office and moving my Benchmark gear to the Livingroom so I can buy my Livingroom speaker faster (save on amp costs). By doing this I would lose the ability to listen to my tuner on a very high-quality local station for 3 hours each morning, however, I could use my headphones for that with the separate headphone amp (built-in pre).

The second thing that I would lose is the integration of my sub (via my preamp), a KEF KC62 sub and KEF LS50 Meta speakers. Can anyone recommend some way to integrate these 2 with the GAN1. I do not want to use the Bluesound Node. I like my Fibre streaming using my Sonore OpticalRendu and want to work with this streamer.

@kuribo, It's not worth my time to continue this one sided discussion.

Well, that took long enough.

I got my LKS LPS-25-USB 5V linear power supply for my yet to arrive LKS DDC for less than $90 shipped from AliExpress. So while I waited for the LKS DDC, I put the LPS on the Node 2i and I was surprised how good the system sounds. I now prefer this SPDIF implementation into my DAC over the USB implementation I was using.  My SPDIF implementatuon also uses a megabucks digital cable so that probably plays a big part in the sound quality.  YMMV

I got the pd creative linear power board for the newer node. I would say it's worth it. The expensive part is the actual power supply that you plug into the board. It's super easy to install. It provides a nice improvement in sound quality. 

@donnylovely It's fun to read about other folk's experiences with their gear but it's more fun to partake in the listening myself in the comfort of my home and within the familiarity of my system 😁

@dolfan I bought a power interface converter for my Node 2i from PD Creative based in Poland. I did the installation myself.  They also make a similar unit for the Node (gen 3).

I will share the results of all my experiments here in this forum so stay tuned.

@kuribo Do you mean Mouser? searched DigiGaN-200s RevA and Gan 1, got nothing. Are you sure you weren’t looking at another amp?...You made up issues but no proof of such issues. You had to get the data from someone else for the one "issue" (more of a nonissue, since it’s not audible) that you were talking about when you supposedly had all the measurements. I am back I have learned something, that you don’t know anything about the gan 1 at all except for what people have told you today....Only one-sided because you are not answering any of the questions, just deflecting.

@donnylovely 

Come back after you have learned something about class d. I have made the issues with this amp abundantly clear to anyone with a minimum of technical knowledge about class d amp design. You can find the data sheets on Mauser, and there is all you need to know about class d amp design and theory at the link I posted below. It's not worth my time to continue this one sided discussion.

@kuribo What would you change with the output filter then? What do you see wrong with the design other than it being "old"? How come you are not sharing any of the info with us still? How come the measurements just posted was news to you? Why can’t you give us any facts? Why do you just avoid the topics and complain about some other random thing?

@donnylovely 

You obviously haven’t looked at the design to tell if that's true or not. . Where are these mythical measurements of yours?

 

I have looked at the design and the data sheets while you clearly haven't. Nor do you understand what an output filter is, nor what the implications are of open loop (zero feedback) design. The more you shoot your mouth off the more obvious it is that you have no idea of the issues.

@kuribo You obviously haven’t looked at the design to tell if that’s true or not. How much better can it be? What specifically would you do differently? Where are these mythical measurements of yours? How come you’re the only one that can see them? Why won't you share them with us? I’m thinking they don’t exist. The measurements just post seemed like they were news to you. 🤔 So weird. It’s almost like you have no idea what you’re talking about and that you just made up a story in your head so that you could practice being bitter. Why are you keeping them a secret? Oh why lol

@donnylovely 

Old tech, this is class d circa 1985. Without any actual understanding or knowledge of class d, that doesn't mean anything to you. The technology has matured and is now capable of much better than out of date designs without post filter feedback. But ignorance is bliss. Enjoy!

By the way, the measurements are out there. Get off your hind end and find if you actually have any interest in intelligently discussing this amps shortcomings. Otherwise you, like your amp, are just distortion boxes.

@ricevs u just start typing the @name and it populates. God Bless u

@sirnui tell us how to hook up the LPS to the Node? I thought it had a connector that was proprietary?

@kuribo yeah your ignorance. You haven’t listened to it yet. drastically short? How so? Which measurement? You keep saying it’s worse but have given 0 examples. Old tech? Like class a, class a/b? Lots of old tech in amps. Being old doesn't mean anything

The module was measured at different impedances:

16 ohm......up .15 db at 20K

8 ohm ......flat at 20K

4 ohm........minus 1 db at 20K (quarter db down at 10K)

2 ohm.......minus 2 db at 20K. (half db down at 10K)
 

So the output filter was designed for a simple 8ohm resistive load. How does it perform with complex loads?

Have you seen the distortion versus power and distortion versus frequency? Poor by current standards.

Just like the 1980’s Tripath. Old tech. Yuck.

@donnylovely

They’re too scared to actually listen to it. What if they actually like it? Their brain might melt.

Scared? Of what? Lol, I've read a lot of bs here but that sets a new standard.

Is there some logical reason that an amp can't both measure and sound good? Great, you like it! Doesn't mean it isn't poorly designed and falls drastically short compared to other cheaper amps. The only thing scary here is the ignorance.

@sirnui Damn, that's a serious system. Idk if the gan 1 can best it or not, but I am super intested to hear your comparison. That would be pretty crazy if the gan 1 is better. Also super intested in your thoughts with the different streamers and this amp. Enjoy! 

The module was measured at different impedances:

16 ohm......up .15 db at 20K

8 ohm ......flat at 20K

4 ohm........minus 1 db at 20K  (quarter db down at 10K)

2 ohm.......minus 2 db at 20K.  (half db down at 10K)

However, the only thing that matters is how it sounds. Seems to sound lovely to most.

Sirnui,

Please contact me through my normal email address (listed on my website).....thanks.

Pokémon is a miserable little troll. 

Let the good times roll!  I just put an order for the Gan 1.  I will see if it can replace 10K+ worth of gear and cables.  My current streamer is a bluesound node 2i powered by an LPS.  I currently use a Shunyata Omega Clock 75 digital cable between the node 2i and my DAC.  I will also test with a HoloAudio Red streamer and an LKS DDC when they arrive.

My system is already on a Giandel inverter and battery thanks to ricevs.  I'm currently using a Puritan PSM 136 power conditioner but I'm also expecting a Shunyata Typhon T2 conditioner in a few weeks. The T2 has two outlets.  If I simplify the system down to the Gan 1 and a streamer then just the T2 would be perfect and simple.

If I end up selling my DAC and amp, that can easily fund purchasing a Grimm MU1 streamer which may be the ultimate mate with the Gan 1.  The MU1's specialty is 176.4/192KHz over SPDIF.  The MU1 was my former streamer. 

@ricevs 100% agree.

They’re too scared to actually listen to it. What if they actually like it? Their brain might melt.

It’s returnable, idk what that kid has to lose. If he bought it, then he might actually know what he was taking about. He does seem oddly infatuated with it for not having listened to it. 

On one hand the "measurements are everything" people (Kuribo, ASR people) say that all amps sound the same......so don't listen to them.  On the other hand they love low distortion measurements.....so they say buy the ones with best measurements (that they like).

Pretty silly way to get a great SOUNDING system.  Just trust the nerds....they are always right. Please no not listen for yourself and choose the one that sounds best to you.  Two people on this thread prefer the GaN 1 to their Purifi amps..........but what do they know!?!.....they just did listening comparison tests in their system......they did not measure.  listening tests mean nothing....the only thing that matters is how it measures......everyone knows this!......ha ha.

Poor anti tweak, anti listening objectivists.....they have nothing better to do but bother people who want good sound.......and who listen.

BTW, my computer Altec speakers sound great.....paid $29 at Fry's for them years ago.....powered....little woofer on floor...amazing sound.  Seriously.  Not as good as my big rig......but makes me laugh, cry and dance with delight.  May you all be merry this season and every day of the year.  Every day is Christmas.....every day is your Birthday......celebrate good times, come on!

Which specific measurements are worse? The gan 1 doesn’t have overheating problems like 2 of those you have listed. Orchard is also a gan amp BTW. 

@donnylovely 

Your GaN measures poorly compared to Hypex, Purifi, Orchard, etc. That's a fact. You say the GaN sounds great, that's just your opinion. I know people who think their computer speakers sound great. So what. Opinions mean nothing. Try again.

@donnylovely Thx. I always thought better conductors, better connectors and more secure connections make a difference. I really don’t remember how the amp sounded stock. It was good, but sounds really good now. I’ll have the ability to compare when I get my 2nd amp. Should be an interesting listen.

Are you serious? None of those amps preform better. Those 3 sound awful. Lay off the kool-aid. You really need to listen to those amps next to the gan 1 before you go spouting off. 

@donnylovely

1db is more of a non-issue than an issue. Sorry we can’t all afford to buy the best preforming amps in the world, that’s more of a non-issue also, always going to be something that preforms better.
 

Now you actually admit the frequency response is load dependent after denying it time and again?

The actual performance into a real world varying reactive load is almost certainly materially worse than than 1dB, which is into a best case, non-reactive, constant resistive load.

We can't all afford to buy the most expensive amps but those who can afford the $1500 GaN 1 can certainly do better for the same or less money. There are plenty of better engineered and performing amps available - Ncore, Purifi, and Orchard, etc. are all much better performing and better engineered without riding the GaN marketing coat tails.

@kuribo what other class D amp in this price range should I try? 

1db is more of a non-issue than an issue. Sorry we can’t all afford to buy the best preforming amps in the world, that’s more of a non-issue also, always going to be something that preforms better.

@atmasphere

Gentlemen. I see that @kuribo has entered this thread. I've crossed swords with him in the past, but on this point of load dependent frequency response he is correct.

Nice to see we agree on something.

To properly evaluate the performance, a simple constant, purely resistive load is not going to do it. Few speakers present such a simple load.

Additionally, without post filter feedback, there are other issues besides load dependent frequency response that can be present.

In all, it's a poor design in comparison to other currently available class d amps that have orders of magnitude better performance. Just more marketing, all aboard the GaN train!

So Ralph, are you saying that the data output (to be sent the the input of the Gan 1) sampled at 96kHz would not necessarily be a restrictive limiting factor to the ultimate performance of the Gan -1?

I am. The limitation is in the word length, not the scan frequency.

Gentlemen. I see that @kuribo has entered this thread. I've crossed swords with him in the past, but on this point of load dependent frequency response he is correct. @ricevs , if you want to find out what the effect of this might be, try a load that varies between 3 and 16 Ohms over the audio band (which is typical of many speakers) and find out what actually happens. Its not sufficient to look at the difference in FR with a simple resistive load.

Now I made a career of building zero feedback OTL tube amplifiers so I have a fair amount of hands-on experience with this. The output impedance of the amplifier plays an enormous role here. So I would expect that the FR of a zero feedback class D amp to be less 'reactive' (if you see what I did there) than that of a tube amp. The variable here though is the output choke, which is a critical part of any class D design, especially a GaNFET, which will require the choke to operate at a lower frequency rather than a higher one, on account of its inductive kickback being used to initiate the off state of the output device.

Its complicated.

Now how much this will affect the audio FR with a variable load is a good question. The On resistance of GaNFETs is stupidly low, so if it were up to them this would be a non-issue. IOW the output filter choke is really the variable. Based on my own experience (since a number of our prototypes were zero feedback) my guess is its a minor issue.

@mbolek those are some nice looking mods. Much higher quality parts it looks like. Have you noticed a significant change in sound quality? 

Thanks kitsap2, Since so many people in this forum like vinyl just wondering have anyone of you had tried it and what's the result.

 

Has anyone tried connecting a turntable using the 3.5mm input on the Bluesound Node and played it on the amp? How does it sound comparing to your pre/power amp? 

So far, the only one I know that has done this is Andrew Clark, president of Peachtree Audio.  Here are his remarks copied and pasted from Peachtree's website:

A few weeks after exhausting my library of demo tracks and personal favorites, I hooked up a turntable to the NODE. (My turntable has a switchable built-in phono preamp so I can connect to the NODE's line in.) I don't know what I was expecting, but I was pleasantly surprised by what I wasn't hearing. It sounded crisp and clear without any background noise or humming. This is great. I'm not hearing anything that makes me believe this input was an after thought or compromised because its a dual input (analog or optical digital audio) or because it uses an ADC inside the NODE. I have ZERO ISSUES recommending that people hook up their turntable to the NODE and enjoy their vinyl on this system this way! It sounds great! I even programmed my turntable as a preset, so when I want to spin vinyl, I just touch the first dot on top of the NODE and lower the tonearm and I'm listening. Easy.

I might consider adding a phono preamp to boost my turntable output a bit. (My turntable's built-in phono preamp has no gain adjustment.) Albums are mastered at much lower levels than today's digital files so when I want to crank up the volume on my vinyl I can sometimes max out the NODE's volume and still be left wanting more. Some of my older CD files (ripped to my computer years ago) have a similar issue. They were mastered at levels significantly lower than today's norms so even when the NODE is set to maximum output, I sometimes could use more. Fortunately most of the earlier recordings have been remastered at some point in the last 20 years, so that helps with the gain/level issue. If my primary listening was vinyl or digital files mastered before say 1990-2000, I would definitely use a phono preamp with gain settings (or higher max ouput than my turntable's built-in preamp) and re-mastered digital files. Or perhaps some other way to affect gain in the digital domain like Roon, Foobar, etc.

Hope this is helpful!

Has anyone tried connecting a turntable using the 3.5mm input on the Bluesound Node and played it on the amp? How does it sound comparing to your pre/power amp? 

@dolfan I do not know much about digital cables, but I do know when some companies do cables right. The 2 companies I trust are Audience and WyWires. I have not spent too much time trying other cables and have just stuck with these 2 because they work for me.

Saying all of this I just went to the WyWire web site and ordered the Silver cable. These cables are 40% off the price you see on the web site.

S/PDIF Digital Audio Cable Litespd – WyWires

I asked Alex to make me a BNC to RCA wire to eliminate an adapter. Hopefully, that was a good choice.

It probably is much better than stock......and you do incredible soldering and work.....looks better than my stuff.  Very professional.

@ricevs I figured the the Illumati would be better than stock. Maybe, maybe not. It is a damn skinny wire. Added a couple of pics to my profile.

I may try using some Triple C copper as the interconnect.

Kinda cool that a $1500 box can have so much potential. It is dead quiet, no heat and sounds better than my reference Purifi. I stopped trying to justify Class A many years ago....

@yyzsantabarbara If Andrew can’t add speakons for you, have Ric swap out. Not more than $10...if you choose not to decide, you still have made a choice.

Speaker loads are rarely purely resistive nor are they flat.

BTW, the GaN 1 digital board measures almost the same frequency response as the board in the GaN 400 (analog input board). It is one db down at 20K using a 4 ohm load. This will give less than one quarter db attenuation at 10K......no one can hear this. However, with a 2 ohm load it is 2db down at 20K.....so it will make 10K down one half db.....maybe you could hear this. OMG this is so horrible!!!! (Kuribo speaking here). There is maybe one person in 100 with a speaker that MAYBE you could hear the rolloff.......I don’t hear much above 10K myself. There are a couple of electrotats that have very low impedance at 20K and there are a handfull of regular speakers that have a 2 ohm tweeter load.......but very, very few. Just go to stereophile mag and read the measurements of various spekakers they have reviewed lately....only the Kef Blade 2 goes a little under 4 ohms at 10k.....all the rest are above 4 ohms......just not an issure.

So, thinking you need feedback and op amps and DACs and Preamps and analog cables so you do not have this very slight problem that practically no one will hear is simply silly. But, some people make mountains out of mole hills.....hey, I get excited for positive things.....some people get excited to put things down.

I like UP myself. I say Yes to life.....and Blessings to all......how about BLESSESS......Beautifully Love Every Single Soul Every Single Second

@wise Santa B

Hoping we both get ours next week. They told me last week I would hear sumn about testing and or shipping but nothing so far.

u have nice systems

Mine will be Gan 1, Node, Tekton Perfect Set, and Rythmik FV15HP. It's a TV and backround music set up.

I need a coax cable. Where would u start?

@dolfan It could be ignorance on my part. I saw the blurb on Peachtree web site that said they have a new batch being built for Dec 2022. I will give them a call to see if they can put some SpeakON speaker termination for me. That way I can do a real apples-to-apples comparison with my Benchmark gear.

I will use the GAN1 amp for my KEF Blade 2 Meta (ordering in Feb 2023) until I get funds for a more powerful amp for the Blades. I was wondering what to do with the GAN1 amp afterwards. I realized that the GAN1 has the protentional to be a great headphone amp for my RAAL SR1a earphones. I want to get a headphone amp for the bedroom and the GAN1 could be a perfect low box count solution. I bought some very short used Audience AU24 SX speaker cables a few minutes ago for that purpose.

As a frame of reference, the best 2 channel gear I had on the RAAL SR1a earphones cost over $20K and I sold all of them since it was not as good as my RAAL VM-1a amp. The VM-1a only works on the SR1a and not speakers so it has some advantages in design.

So, I now have 2 comparisons to do with the GAN1.

1) Benchmark stack vs GAN1. I will have to downgrade my speaker cable for this comparison to Audience Conducter SE unless Peachtree can do SpeakON termination for me.

2) CODA 07x preamp | KRELL DUO175XD amp | Musetec 005 DAC | Audience FrontRow speaker cable vs GAN1. I still remember how this sounded since I listened for hours each night for over a year. I will use the just purchased Audience AU24 SX speaker cable which is one notch below the FrontRow so it should be a close approximation.

@donnylovely

Maybe this will help...

From:

https://sound-au.com/articles/pwm.htm

Class D Audio Amplifiers - Theory and Design

6 - Output Filter Design

The output filter is one of the most important parts of the circuit, as the overall efficiency, reliability and audio performance depends on it. As previously stated, a LC filter is the common approach, as it is (theoretically) lossless and has a -40dB/decade slope, allowing for a reasonable rejection of the carrier if the parameters of the filter and the switching frequency itself are properly designed.

The first thing to do is to design the transfer function for the filter. Usually, a Butterworth or similar frequency response is chosen, with a cutoff frequency slightly above the audio band (30-60KHz). Have in mind that one of the design parameters is the termination load, that is, the speaker impedance. Usually, a typical 4 or 8 ohm resistor is assumed, but that would produce variations in the measured frequency response in presence of different speakers. That must be compensated for by means of proper feedback network design. Some manufacturers simply leave it that way so the response is strongly dependent on the load. Surely a non-desirable thing.

7 -   Feedback

As I have stated previously, timing errors can lead to increased distortion and noise.  This cannot be skipped and the more precise it is kept, the better the design will perform.  Open loop Class-D amplifiers are not likely to satisfy demanding specifications, so negative feedback is almost mandatory.

And there you have it...

@art_boston

Seriously? This is certainly something to care about, if you have any clue about amps.

He is clueless, don’t waste your time. The FACT is open loop (zero feedback) amps are load dependent - the output filter interacts with the load, that is one reason why modern designs use feedback after the output filter. Simple physics which can't be ignored, as much as one tries.

@singintheblues

Back on topic, any ideas on what type of speakers work best with this amp?

 

That’s the gist of the problem, isn’t it, with amps that have load dependency? For modern designs which avoid that issue it isn’t a thing. Try something with a flat impedance curve that is basically a resistive load. Good luck.

@art_boston I stand corrected, only 2 people care about. I only care about sound quality. I'll never send my personal stuff to those jokers at ASR. They can buy their own gan 1 and be smug about their measurements. 

@kuribo the guy in denial, which would be you. You haven't given any facts. 

@donnylovely   "...complaining about some "issue" that no one cares about"

Seriously? This is certainly something to care about, if you have any clue about amps.

Until these new wonders can run my Acoustats, or any difficult load, they're not worth a dime. Heaven forbid manufacturers post their 2-ohm ratings!

I dare anyone owning this amp to send it to ASR. Yes, I know they don't give a damn about sound quality. But they do give a damn about the flip side of the audio coin: measurements.

@wise Santa B why do you expect delivery next week? I am waiting too.......

Thanks for this thread folks I NJoy it! U R All WAAAY above my pay grade