Pass Power amp advice needed

[john11]

Hi And thanks for reading this thread.
I am wanting to build a pass amp and will appreciate any advice on the following boards. How do they look? Have you tried them or heard anything about them.
https://www.ebay.co.uk/itm/2pcs-HIFI-Power-Amplifier-Board-MosFet-2-3-PASS-Aleph-30-A30-Audio-Amp-DIY/273760488977?hash=item3fbd658e11:g:KFAAAOSwf4BcikEv
https://www.ebay.co.uk/itm/PASS-F5-25w-A-class-amplifier-D-I-Y/113207731427?hash=item1a5bb4e4e3:g:LUkAAOSwTHRbdzyp
https://www.ebay.co.uk/itm/2x-PASS-A3-HIFI-Class-A-Amplifier-Board-Single-Ended-Amp-IRFP250-30W-8ohm/282882596944?epid=7005275414&hash=item41dd1de050:g:L8QAAOSwlXhZZymE
Many thanks

 

[PENG]

Hi And thanks for reading this thread.
I am wanting to build a pass amp and will appreciate any advice on the following boards. How do they look? Have you tried them or heard anything about them.
https://www.ebay.co.uk/itm/2pcs-HIFI-Power-Amplifier-Board-MosFet-2-3-PASS-Aleph-30-A30-Audio-Amp-DIY/273760488977?hash=item3fbd658e11:g:KFAAAOSwf4BcikEv
https://www.ebay.co.uk/itm/PASS-F5-25w-A-class-amplifier-D-I-Y/113207731427?hash=item1a5bb4e4e3:g:LUkAAOSwTHRbdzyp
https://www.ebay.co.uk/itm/2x-PASS-A3-HIFI-Class-A-Amplifier-Board-Single-Ended-Amp-IRFP250-30W-8ohm/282882596944?epid=7005275414&hash=item41dd1de050:g:L8QAAOSwlXhZZymE
Many thanks

I like the F5, that looks to be a normal class A amp without any "voicing". The Aleph probably won't be exactly neurtral/accurate but you are going to have to ask Mr. Pass if you want to be sure as I am only going by memory of what I read about them.

 

[john11]

Hi. Thanks for the reply.
I like the look of the F5 as well. Do you think the 25 watts it offers is going to be able to drive a high sensitivity speaker, because i read somewhere that 25 watts class-a is more like 40 watts in loudness compared to class a/b.

And what do you think of the layout? The design is very old how, do you think it may be okay or outdated.

Thanks.

 

[NINaudio]

Do you think the 25 watts it offers is going to be able to drive a high sensitivity speaker,

Depends on how far away your listening position is, as well as what you consider to be high sensitivity. There are lots of spl calculators that you can google to determine how loud a 25 watt amp can drive different sensitivity speakers.

 

[john11]

Thanks, was i right that 25 watts class-a sound louder than 25 watts class a/b

 

[NINaudio]

Thanks, was i right that 25 watts class-a sound louder than 25 watts class a/b

no idea

 

[Verdinut]

no idea

No, 25 watts of power in either class is the same power.

 

[john11]

Thanks.

May i have some more feedback on the boards, how do they look to you. I am leaning towards the f5 as it does not have many components to get in the way of the signal. A simple layout, or is it too simple.

If not, are there any boards you have tried and liked the results of. I am wanting something hifi.

 

[PENG]

Thanks.

May i have some more feedback on the boards, how do they look to you. I am leaning towards the f5 as it does not have many components to get in the way of the signal. A simple layout, or is it too simple.

If not, are there any boards you have tried and liked the results of. I am wanting something hifi.

I can't give you feedback because I bought mine from:
https://diyaudiostore.com/products/f-5t
https://diyaudiostore.com/collections/jfets/products/linear-systems-matched-jfet-pairs-grade-b?variant=5938441988

I prefer that site because they sell match sets of the JFET output pairs.