Aleph J vs. Jean Hiraga 25W vs. Ovation SX

[Alan Meyne]

Am returning to DIY after 2 decades... Am in awe of the great minds, hands and ears on this forum. Am conteplating on building a Class A amp and have followed threads on this forum and others on: Aleph J, Hiraga 25W, and Ovation SX. Knowing that auditory appreciation is highly subjective, I would love to know which one of these would you choose to build and enjoy and why (assume cost and complexity is not a concern). This will greatly help me in making a choice Thank you so much for reading this and responding.

best regards,
Alan

 

[hifiramr]

I will recomend ovation SX amp which is well documented and a well perfomer and is derived from Hiraga and JLH designs you can get all details from below link with strong diyaudio forum support

Ovation sx-Amplifier: A 15 W RMS class A Current Feedback Amplifier

I have build his class AB NX amplifier and is truely a beautiful amp.

 

[Alan Meyne]

Hello hifiramr,

Thank you for your advise! Would you recommend obtaining the pcb and components from Jim's audio?

What aspect of Pass design do you like/dislike?

Regards,

Alan

 

[anilva]

I built a Aleph J along with a host of other Firstwatt designs. Aleph J is an outstanding performer and is a single ended class A design. Has a balanced sound signature and extreme resolution typical of a Pass design. I have not heard Jean Hiraga enough to comment.

Cheers.

 

[hifiramr]

Hello hifiramr,

Thank you for your advise! Would you recommend obtaining the pcb and components from Jim's audio?

What aspect of Pass design do you like/dislike?

Regards,

Alan

Hi Alan yes the designer itself given permission to jims audio for the PCB.So you can buy from Jims and the PCB is in excellent quality.ALso you have to order parts from various sources also I think I have some parts with me too so I can also help.Please check his site he documented everything in a pdf file.Also he will respond to diyaudio forum very quickly.Making hi watt class A amp is a bad idea lot of heat and waste of money.Not a clever idea

But please check all designs on the net and decide what you need its up to you

 

[Alan Meyne]

Hi Anilva,
Thank you. I salute you for the wonderful projects that you have completed and the support you provide for green horns like me!
I have not personally heard any of these amplifiers in action...How would you rate the bass resolution and depth of Aleph J? One thing I am hoping is to be able to hear the bass line clearly (not loudly) and not as a background mumble... I have a Tannoy DC6T speakers currently hooked to Azur 651 Amp and CD, source is a rebuilt Technics SL Q3 and DIY phono stage and Yamaha KX-W421 tape deck.
Regards,
Alan

Hi Hifiramr,

Thank you, I will check his website as you suggested. There seems to be some issues with the PCB for the sx from the chat I have observed on 22nd Dec 2015...Any thoughts?
Regards,
Alan

 

[hifiramr]

I think its fine but you can directly check on the forum and ask him regards this.

sx-Amp and nx-Amp - Page 164 - diyAudio

You can look on his NX amp SX and NX both sound similar I recommend class AB which dont have much difference in sound quality for some designs like NX.If you want to do a one time investment in diy build I will recommend one clone which is very superior

JFET Input High Speed MOSFET Power Amplifier PCB Telos | eBay

you need two pcb for the build and which is the clone of famous "Goldmund Telos 390" orginal price was around $10000 + I think so

But clone will not be perfect with orginal but if you get more than 80% of orginal then you can imagine how it sounds.In diyaudio forums some of the experienced fm using this as there reference amplifier.

See the below liink for some build images you will like it

http://www.quebecdiy.net/t126-goldmund-telos-390-clone

 

[GeorgeO]

Good luck with your build, it's an interesting journey!

 

[Alan Meyne]

Thank you so much Hifiramr! I have had a quick look at it and will continue to research it. Are components available? do I have to match components closely? Thank you.

 

[hifiramr]

Yes components are available but some components are costly you can get marched pairs from various site on the net.But cost is important that's why I suggested one time investment.According to my calculation for both board populated it will come around 15k plus

 

[jls001]

I've been following the Ovation amp thread on diyaudio. Jim's Audio does seem to be authorised by Ovation/Bonsai to make and sell boards. Just for info, please.

 

[captrajesh]

I've been following the Ovation amp thread on diyaudio.

The SX looks like very interesting design. Leaves Class A @ 15 Watts and continues in Class AB upto 25 Watts.

Has anyone made it here?

 

[hifiramr]

SX amp is very beautiful amp to build and it sound beautiful.I have build his NX amp 100 W class AB and it sounds amazing.Its a must build amp

 

[captrajesh]

SX amp is very beautiful amp to build and it sound beautiful.

Have you heard it anywhere?

 

[sathiamoorthy]

Looking if anyone is having it. I can request them to let me listen to it.

 

[hifiramr]

Have you heard it anywhere?

I already mentioned that I have build its class AB NX amplifier and now I am running it with my Spendor S3/5 se with Akido tube preamplifier its excellent.

Both NX and SX sound similar.But SX is in class A mode and it will be far superior to use with full range speakers.As one of our forum member just ordered pcb from jims and he is going to start his build soon.

Please check one the build from diyaudio forum

sx-Amp and nx-Amp - Page 167 - diyAudio

 

[captrajesh]

I already mentioned that I have build its class AB NX amplifier

I've already read that post. I was checking if you have heard the SX personally.

Both NX and SX sound similar but SX is in class A mode

An amp which works in Class A mode up to 15 watts and then shifts into Class AB mode to deliver 10 more watts should sound different from the one which delivers up to 10 watts in Class AB mode should not sound same, theoretically speaking IMO. Was this your personal experience?

one of our forum member just ordered pcb from jims and he is going to start his build soon.

Thank you for the heads up. Hope you wouldn't mind mentioning his name. I also hope he would document his build on HFV. It will be educative and inspirational.

 

[hifiramr]

I am not an expert to explain in detail but what it differentiate is biasing the basing will decide to run in class A or AB mode.High bias will be result in class A operation for further details please read on the sx pdf file which is very well explained.

http://hifisonix.com/wordpress/wp-content/uploads/2014/11/The-sx-Amplifier-V2.09.pdf

our FM manniraj is going to start the build. I will tell him to document his build in our forum