Millett Hybrid MiniMAX

[adn6244 0]

It's started at this Headfi thread HERE

 

Poisoned by the enclosure group buy HERE So I dive in and ordered the casing

 

Ordering my pcb HERE soon...money..money...money

 

Found people mentioned Blackgate from HERE

 

Question : Is Blackgate really worth getting? Does wellaudio stock them?

 

(I'll try to update this thread when I have more info)

Edited October 28, 2008 by adn6244

[heady 0]

C'mon man, don't despair. It's worth it.

 

I am not so convinced re: the Blackgates. You can always try Polypropylenes capacitors. I think you may have to order from overseas, if you want the Blackgates.

[adn6244 0]

I think I'll stick to Farnell for convenience sake. Will start the ordering process tonite or tomorrow

[mouz 0]

You can try getting blackgates from ahfartaudio, I got mine from there before for a sound card mod (x-fi).

http://www.ahfartaudio.com/about/contact.html

 

Frankly speaking, I'm not so sure about black gates though. The amount of money spent on one blackgate can buy many other 'boutique' caps (like muse, silmic, etc) if you're considering using them in the signal path. Who knows? They might sound better too.

 

[adn6244 0]

OK...collected the little box from singpost this morning...pcb and tubes are nicely packed in the box...

 

 

 

 

box is delay, parts are coming in early next week from mouser...they are having promotion for order above S$130 Fedex free shipping is provided so decided to just order all from them...lazy to source for the parts from Farnell one by one again

 

not sure the photo are too big here

Edited November 15, 2008 by adn6244

[mouz 0]

Free shipping? alamak, should have hooked up with you man. I got some stuff to order from there for my MH too....

[adn6244 0]

mouz, you got pm.

[adn6244 0]

Found this in the Millet Max construction note :

Matching Transistors -

A good place to start the Max is to match the transistors. In the case of the Max, this means the 2N5087 and 2N5088 transistors. Matching the JFETs and BJT output transistors has limited usefulness. Matching the MOSFETs if you use that option is a good idea...........

 

Is the matching really necessary? Did you match the transistor when you build your Max?

 

For Minimax, if the set up is BJT Diamond, but for Max it has limited usefulness...confused..

 

 

[mouz 0]

Getting those transistors locally is not an easy feat, better off ordering already matched ones from beezar. BTW, are u building the mosfet or BJT version?

[adn6244 0]

The default parts are BJT and I ordered the Q8 and Q9 transistor from beezar.

 

But Q2B(2N5087) and Q3B(2N5088) only Mouser parts are listed so I am not sure these 2 must be matched too.

Edited November 18, 2008 by adn6244

[mouz 0]

Well according to the instructions, it seems that they do need to be matched. Not too sure if there'll be any sound diff or not, prob slight.

http://www.diyforums.org/MAX/MAXconstruction.php

[lucifix 0]

Wow this is one cool DIY amp, great pictures!

[Duck-in-the-Box 0]

whats the total damage? is it done? lol

[adn6244 0]

here are the updates : (photo to be added tomorrow...battery flat..charging now )

 

Costs (All approx as I seldom track so detailed) :

S$130 Casing from the group buy incl shipping (still waiting)

S$80-100 Components from Mouser (Shipping FOC as total > S$130 combined with parts for other proj)

S$30-50 for boards and tubes from beezar (rough estimate )

 

Bought a cheap DMM that can measure HFE for approx $18 from koba

 

Luckily most of the transistor for 2N5087 and 2N5088 can be matched and paired.

- 2N5087 are from the same batch so they are all in 490-495 range...I assume the DMM is working

- 2N5088 has wider range from 430-620, almost all can be paired and match with less than 50HFE gap except for one pair which cause 100HFE difference but since I want to complete the build... I didn't use them in the critical positions but they are in.

 

Board are 90% populated...still thinking whether I should order Muse ES or other "boutique" caps for the output positions. Otherwise it should be 99% complete by now. 1% for the missing caps I forgot to order

[alvin1118 0]

i was told that transistor matching aint just measure and match the hfe(beta) value ? found this matching circuit online...