DIY FirstWatt F4 and McIntosh C48?

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DIY FirstWatt F4 and [McIntosh C48] ---> Herron VTSP2?

I have just picked up a McIntosh C48 and am wondering how best to connect it to a future build of a FirstWatt F4.

Do I need a Pass BA-2 VAS stage included in the f4 build, or can I connect the f4 straight to the C48 with good results?

Thanks!

Kind regards,
Peter
 
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Thank you Mr Pass! An excellent answer in the true spirit of DIY!

Thanks Jvhb. I would like to have the full power available, so I will stuff the BA-2. I have bought a partially built f4 from a guy who can also supply some of the hard to get parts for the BA-2. I will snap a few photos and a list if missing parts - just to keep track of it myself.
Peter.
 
While I wait for another post to vbe approved, I have made the following "What I need to buy or check list for my build of the f4 amp. I will build the "Liberated" type f4 power amp:

What I need:
Case : Front / back / bottom / Top (I have humungous heat sinks)
Soft start module (CL60 or another high quality type)
Front Led
insulators
board mounting standoffs, w/ bolts and washers
Mounting bolts for fets w/washers, high quality keratherm insulators
Speaker Terminals and RCA Jacks
Power Connector
Power switch

BA-2 ”stuffing”
4
10K
R201, R202
4
47,5K
R203, R204
2
1K
R205
2
221R
R206
2
100R
R207
4
750R, 3w
R208, R209
4
47,5R
R210, R211
2
150R
R215
2
5K
P201
4
20pF
C201, C202
2
10uF, 35v
C203
4
1000uF, 35v
C205, C206, C208
(I have SJ109V+2SK170+IRF610)

I also have 2SK1530/2SJ201 for the output stage (missing from the build)
- Need to check 27K values that should be 22.1K on the board(s) (print fault in build diagram used for this)
 
Kevin.

Why is this?

Originally I considered buying the Pass Int 30 (integrated) but then got a good deal on the McIntosh C48 pre. I had listened to a McIntosh 6600 on what was my speakers then (System Audio Pandion 2) but I did not like its sound. Then the dealer added the McIntosh C48 using the 6600 as power amp. That sounded much better.

But the biggest surprise to me was that at home with my Naim Nap 160 power amp on Rogers LS2 with both PC (ESI Juli@ sound card analogue out) and a moddded Thorens TD160 MKII+Morch UP4+ Denon 103R as souces, my set-up sounded very much better than it had any right to.

The McIntosh C48 has meant a very big leap in sound quality as compared to my 70s/80s Naim set-up. I would say close to Naim Nac 252 territory (another SS pre that I used to have in the house).

Still, I covet a slice of the Mr Pass sound.

My study is quite small, so I don't need that much amplification in here.
 
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I'm sure the BA2 vas and F4 would make nice sounding amp. I just think there might be an easier way to build yourself a NP amp. If you were to build an F6 you could buy the deluxe 4U chassis, F6 kit with board and transformers, jfets, insulators, power supply board, and I believe a hardware kit all from the store. The chassis is all predrilled and taped. You just need to source passive components, transformer, and assemble. So you would have something relatively easy to assemble by following the build guide. It would be consistent with other members builds who will be helping you along the way, especially when it comes to troubleshooting. In my experience there's always troubleshooting.

I understand the F6 kit and 4U deluxe chassis are out of stock so it would take a little patients.
 
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When I ordered, I used the DIYaudio order form, so I certainly expect any predrilled holes to match the DIYaudio specs.

I ordered it with a black anodised front with some milled aluminium handles to make it match the look of the C48 which has aluminium coloured "accents" where hanles could be mounted, no doubt.

EDIT: Now I have two humungous heat sinks to spare ..
 
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Everything you need to assemble the case is provided
However cause I ordered directly from modushop with diyaudio order form, I had to order a back panel kit separately from the diyaudio store containing iec socket, rca jacks, binding posts, stand offs, washers, nuts, bolts etc.

In terms of tools all you need is a screw driver to assemble the case, and allan key for mounting mosfets using m3 hex socket bolts. A couple of spanners to tighten nuts maybe useful.
 
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I have a few more noob questions:
What size screws will I need to use in the pre-drilled case?
Is there a parts list with parts order numbers anywhere in existence?
Has anyone built the f4 stereo version with balanced inputs to BA-2 (like the ones I would have from my McIntosh C48 pre)?
Thanks!
 
I have a few more noob questions:
What size screws will I need to use in the pre-drilled case?
Is there a parts list with parts order numbers anywhere in existence?
Has anyone built the f4 stereo version with balanced inputs to BA-2 (like the ones I would have from my McIntosh C48 pre)?
Thanks!
If you order a back panel kit from diyaudio store it will contain everything you need to mount the board, mosfets, iec, rca, and binding posts.
Email the diyaudio store and ask for the back panel kit.
 
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