So. Left hand now in use again. Summer holiday in Camogli, Italy over. All this means that the Cool Danish summer weather beckons a return to the F4. In particular because I have an Ear 868 in the house. I can't wait to have a working F4 here also.
Challenges: revisit the build manuals, build the gain stage, check the config of the psu (Aleph-3 Power supply), fitting the puzzle of inputs-soft start module-gain stage-power amp cards-psu-transformer-output to balanced (connect +test everything. Oh and did I mention that I have little skills in soldering? I need to practise.
Challenges: revisit the build manuals, build the gain stage, check the config of the psu (Aleph-3 Power supply), fitting the puzzle of inputs-soft start module-gain stage-power amp cards-psu-transformer-output to balanced (connect +test everything. Oh and did I mention that I have little skills in soldering? I need to practise.
A bit of progress:
I drilled and made new screw holes in the heatsinks for the amp boards (rev. 1) and mounted the jfets with oversize washers (only ones I could get my hands on). I need to check the schematic against the amp boards to see if all resistors are the correct ones (as I seem to recall that values were changed from the very first schematic to a later one).
Photos:
https://1drv.ms/f/s!AuxF4gJ_6qu_xHR_JZV4quysFqEv
I drilled and made new screw holes in the heatsinks for the amp boards (rev. 1) and mounted the jfets with oversize washers (only ones I could get my hands on). I need to check the schematic against the amp boards to see if all resistors are the correct ones (as I seem to recall that values were changed from the very first schematic to a later one).
Photos:
https://1drv.ms/f/s!AuxF4gJ_6qu_xHR_JZV4quysFqEv
Last edited:
Another day at the office:
Checked the value of R8 and it was the correct one (22.1k) on both amp boards.
Drilled holes and mounted the soft start module on the back plate.
Slow but sweet:
https://1drv.ms/f/s!AuxF4gJ_6qu_xRVX4GEEh6kWhARn
Checked the value of R8 and it was the correct one (22.1k) on both amp boards.
Drilled holes and mounted the soft start module on the back plate.
Slow but sweet:
https://1drv.ms/f/s!AuxF4gJ_6qu_xRVX4GEEh6kWhARn
Have contact with an exprienced local DIY.-gentleman. I hope to learn a few tricks.
Also may have got myself a back-up power amp, an ESS 200 - a company I understand that Mr. Pass once worked for at the beginning of the 70s. However, Mr. Pass was probably busy learning his trade by building speakers / cross-overs. It would be one hell of a coincidence to have two "Nelson Pass amps" in my posession.
Also may have got myself a back-up power amp, an ESS 200 - a company I understand that Mr. Pass once worked for at the beginning of the 70s. However, Mr. Pass was probably busy learning his trade by building speakers / cross-overs. It would be one hell of a coincidence to have two "Nelson Pass amps" in my posession.
Back to the build: Pre = Ear 868L + Eastern Electric Minimax BBA bufffer
So, a long long time has passed with my F4 build gathering dust in a closet. Within a few days I will take delivery of an Eastern Electric MiniMax BBA buffer, so I don't think that there is any need to populate the BA2 board. Thus I can finish the build quite a lot sooner than expected. I will not need to solder at lot (which is a god thing, I believe).
For the testing I will have to have some help from local people, however.
My set-up has changed:
- I traded in the McIntosh C48 for an EAR 868L
- I will use a buffer pre (the Eastern Electric MiniMax BBA) between the 868L and the FirstWatt F4 to see how that works out.
I have been more tied up with work - teaching English - than expected, so now that I have a good five week stretch of holiday ahead of me, I will dust off the project and see if I can finish it before going back to work.
So, a long long time has passed with my F4 build gathering dust in a closet. Within a few days I will take delivery of an Eastern Electric MiniMax BBA buffer, so I don't think that there is any need to populate the BA2 board. Thus I can finish the build quite a lot sooner than expected. I will not need to solder at lot (which is a god thing, I believe).
For the testing I will have to have some help from local people, however.
My set-up has changed:
- I traded in the McIntosh C48 for an EAR 868L
- I will use a buffer pre (the Eastern Electric MiniMax BBA) between the 868L and the FirstWatt F4 to see how that works out.
I have been more tied up with work - teaching English - than expected, so now that I have a good five week stretch of holiday ahead of me, I will dust off the project and see if I can finish it before going back to work.
Another thought: will my EAR 868PL be able to swing enough volts and gain to use the F4 without the Buffer? Hmmm.
But really, I just need to place everything and wire them together as tidily as can be ssen in the F4 build guide. Then I will have to take the amp to someone who can help me test and adjust the power amp as I don't trust myself to do that properly.
But really, I just need to place everything and wire them together as tidily as can be ssen in the F4 build guide. Then I will have to take the amp to someone who can help me test and adjust the power amp as I don't trust myself to do that properly.
EAR 912 in the house
Alright. Lots have been going on here (yet not with the F4 FirstWatt build ...). I now have an EAR 912 in the house. I also bought a renovated Amcron / Crown D150 Series 2 power amp to tie me over since I am taking such long time getting on with my build of the F4 FirstWatt.
Next I am going to place a table in my study. On that, I will put my FirstWatt F4 build so I have eastý access to it on a daily basis. Until now I have had to put it away in a closet at the end of every build session. This way I can slowly get on with my build slowly but surely.
I will first try to finish the F4 build without the BA2 buffer in.
Alright. Lots have been going on here (yet not with the F4 FirstWatt build ...). I now have an EAR 912 in the house. I also bought a renovated Amcron / Crown D150 Series 2 power amp to tie me over since I am taking such long time getting on with my build of the F4 FirstWatt.
Next I am going to place a table in my study. On that, I will put my FirstWatt F4 build so I have eastý access to it on a daily basis. Until now I have had to put it away in a closet at the end of every build session. This way I can slowly get on with my build slowly but surely.
I will first try to finish the F4 build without the BA2 buffer in.
Last edited:
I just built a Preamp with Aksa specifically to be able to drive the F4 here:
AKSA's Lender Preamp with 40Vpp Output
It's really simple and sounds superb.
AKSA's Lender Preamp with 40Vpp Output
It's really simple and sounds superb.
So another few months went by. Today I started looking at wiring as that is basically my next step if I can do without the BA2 frontend.
I have the following (assembled)-not everything mounted
- an Amplino 88014 toroidal transformer - mounted
- an Avondale soft start module mounted on the back panel of the 4U enclosure
- a psu ready - mounted
- two mounted F4 boards ready
- wires galore (shielded and unshielded)
- 4U Deluxe enclosure with all components mounted
- One bridge barrier + 2 x bridge rectifiers: none of them mounted
I have changed set-up once again:
EAR 802 preamp
Partridge 977 SUT
EAR 516 (in the UK for service)
Thorens TD 147 Jubilee + TP 16 + Benz Micro Gullwing SLR
Line Magnetic 502 CA DAC with Mullards and Tungsol rectifier valves.
Quad ESL 57 (with One Thing bass panels)
I have the following (assembled)-not everything mounted
- an Amplino 88014 toroidal transformer - mounted
- an Avondale soft start module mounted on the back panel of the 4U enclosure
- a psu ready - mounted
- two mounted F4 boards ready
- wires galore (shielded and unshielded)
- 4U Deluxe enclosure with all components mounted
- One bridge barrier + 2 x bridge rectifiers: none of them mounted
I have changed set-up once again:
EAR 802 preamp
Partridge 977 SUT
EAR 516 (in the UK for service)
Thorens TD 147 Jubilee + TP 16 + Benz Micro Gullwing SLR
Line Magnetic 502 CA DAC with Mullards and Tungsol rectifier valves.
Quad ESL 57 (with One Thing bass panels)
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.