MF A1 Clone

[dhengkoel]

Dear All;

Can we start to clone the Musical Fidelity A1 now?
I plan to make the MF A1 clone and combine with modified DOZ pre-amp.

regards:
ragil.hastomo

[Zen Mod]

probably you know that already....
http://www.tcaas.btinternet.co.uk/

with or without thread, here on DIY we can find plenty informations of A1

I cloned A1 before 12-15 yrs (I can't remember exactly...)
if you have any question,I'll try to answer....

[lineup]

Originally posted by dhengkoel
Can we start to clone the Musical Fidelity A1 now?
I plan to make the MF A1 clone and combine with modified DOZ pre-amp.

Mark Hennessy has a lot of good info on Musical Fidelity A1.
He has done some tweaking/modifying.

http://www.mhennessy1.f9.co.uk/mf_a1/index.htm

[Zen Mod]

dhengkoel
if you want-I'll send you pcb pattern and parts placement ;
in handwriting,ages ago before (at least - mine) software pcb tools


I didn't bother with A1 preamp part-it's pretty bad,comparing to power amp part

this days,I'll go just with Mini A,or A100 at least (more Voltage and Current through output ) .

[Herrmann]

Hi

Choky: I would be interested in your pcb pattern as well.

Can anybody explain how the quiescent current is controlled in the MF-A1?

Regards, Torben

[Zen Mod]

Originally posted by Herrmann
Hi

Choky: I would be interested in your pcb pattern as well.

Can anybody explain how the quiescent current is controlled in the MF-A1?

Regards, Torben

I told ya that this pcb is pretty crude

tonight I'll upload it to my www,and post exact link here

go to hennesy's and read-I think that you'll find needed info regarding currents etc

if not,I"ll try to explain here

[Zen Mod]

http://czsr_bac.on.neobee.net/MF%20A1.zip

or via
http://choky.on.neobee.net/various.html


about 380 KB zip file
schematics is in fact more of informative nature-during scan process maybe I deleted something; didn't checked;
anyway- consult other schematics from mentioned sources

part designation and BOM are based on actual MF original PCB markings


schematic is upside-down ,contrary to convention - I place minus supply line on top,and plus on bottom

just came in tat way when I drew it from dismantled amp


worth to mention:
origigi PS is more than wimpy
for ~ 80VA of dissipation,you must use at least 300VA tranny,not 80VA as in original A1
10mF-0,47E-10mF (all that twice-for + and - ) is barely enough for both channels

if you use the same just for one channel,amp is dead silent with ear on cone-no hiss,no hum.....just pure blackness...... sorta silence gene??!

input elcos changed to blahblah Wima something
all resistors mf 1/3W ,except few wirewwwwww and few 1Watters for drivers

zenners-plain vanilla 1W3


etc

piece of cake

I was interested in CCS-ing one half,even bothered Papa Nelson with that,but-fortunately-he is busy enough and I'm not interested any more in that solution

build A1 or ,preferably,A100- just from memory-around 2x 33VDC and 1A3~1A5 through output stage

must be better ,but-then we are almost in bigger Alephs and KSA50 area....
anyway-nice little amp-maybe is still best solution to make it plain A1 with beefed PS, to keep it cheap and small.....

[dhengkoel]

Dear All;

thanks choky, lineup, torben for your replies and information

i've already ordered the pcb's (i'm not make it myself), but that's not finished yet ..

choky:

I didn't bother with A1 preamp part-it's pretty bad,comparing to power amp part

so i use DoZ preamp ..

http://czsr_bac.on.neobee.net/MF%20A1.zip

or via
http://choky.on.neobee.net/various.html

i can't get your file

torben:

Can anybody explain how the quiescent current is controlled in the MF-A1?

i think from r6 and r11, i will try it as soon as possible my pcb's ready ..

thanks & regards:
ragil.hastomo

[Herrmann]

Hi

Choky, your ZIP-file seems to be corrupted - will you please try again.

Torben

[kartino]

dhengkoel,

Opo kabare rek?? (LOL, our native......).

Do you a fan of class A? I would like to ask how good your last class A. I am currently on test of 100W class D, mail me private to kartino@inbox.lv if you interested.

Monggo mas.....(**)
Kartino