Maybe I wrote it too bad 😀 I intend to use the F3 only for fullrange in SLOBS. Caps bank with 15mF will not be used on that setup (I'll place another pair of opt sockets on rear panel). I'm building a modified ACN in order to use another amp for the woofer section.
OK, yes, very similar approach. I also have a set of F3 boards from the recent GB and will likely use them as you describe.
At the moment I have one of Lester's chip amps available for bass duties with the SLOB but also have PCBs and some parts for a number of other candidate amps.
I saw that Aliexpress has some interesting chokes now for the Choke Loaded Mah:
--> A choke coil for Class A transistor power amplifier DC filtering, 8A 9mH 0.1Ω common mode choke coil Z11 material EI96 x 50|Transformers| - AliExpress
And it is great for your daily exercise of taking amplifiers out of the cabinet and placing them back, being about 3 kg each.
--> A choke coil for Class A transistor power amplifier DC filtering, 8A 9mH 0.1Ω common mode choke coil Z11 material EI96 x 50|Transformers| - AliExpress
Z11 iron has good audio properties, being thin laminated.
And it is great for your daily exercise of taking amplifiers out of the cabinet and placing them back, being about 3 kg each.
I had a quick look. Shipping to Canada costs as much as the choke itself so total cost would be the same as a Hammond 193V provided additional costs such as brokerage fees and taxes are not added.
The inductance quoted is much lower than the Hammond although the current capacity is higher and dc resistance is much lower.
However, the quoted numbers are confusing to me. The series versus parallel connection inductances do not make sense. The choke apparently has two windings and they are parallel connected, with the label on the choke specifying 8A 7mH 0.1 Ohm.
In the Product Details, the choke is described as having two windings of 4A 9mH, and that they can be connected in series for 4A 80mH and 0.1 Ohm.
My guess is the choke is probably good for 7mH in parallel as shown on the label and 28mH in series.
The inductance quoted is much lower than the Hammond although the current capacity is higher and dc resistance is much lower.
However, the quoted numbers are confusing to me. The series versus parallel connection inductances do not make sense. The choke apparently has two windings and they are parallel connected, with the label on the choke specifying 8A 7mH 0.1 Ohm.
In the Product Details, the choke is described as having two windings of 4A 9mH, and that they can be connected in series for 4A 80mH and 0.1 Ohm.
My guess is the choke is probably good for 7mH in parallel as shown on the label and 28mH in series.
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Yes, I had a look at those Chinese chokes earlier and found myself questioning the overall VFM...
Anyway, I've been working on my build of Ben's Follower today - started bolting bits together - I would have made more progress but have had to order some new bolts as I have forgotten where I put those I previously ordered - I seem to be having these episodes more frequently nowadays! 😉
Of course, the original bolts will be on the work bench tomorrow morning.
Anyway, I've been working on my build of Ben's Follower today - started bolting bits together - I would have made more progress but have had to order some new bolts as I have forgotten where I put those I previously ordered - I seem to be having these episodes more frequently nowadays! 😉
Of course, the original bolts will be on the work bench tomorrow morning.
That would be too easy. If it was me, they would show up only after I received the new order.
Ah math class 101. You are right, 2^2*7=28 , , , and getting 80 would imply a series inductance of 20.
The replacement bolts arrived today, (and yes, I found the originals on my office desk!) so I set to with some assembly.
I have decided to use the SLB Cap Mx supplies, that were originally destined for a MoFo build, so I installed and checked out the first one to see if it contained any magic smoke. Load resistor is pulling less than 100mA but it checked out fine. I'm measuring 42VDC on the output but that'll obviously drop under a proper load.
The transformer sits snugly into the U channel section that forms the bottom of the chassis so all AC will be confined to the lower back part of the chassis.
I have decided to use the SLB Cap Mx supplies, that were originally destined for a MoFo build, so I installed and checked out the first one to see if it contained any magic smoke. Load resistor is pulling less than 100mA but it checked out fine. I'm measuring 42VDC on the output but that'll obviously drop under a proper load.
The transformer sits snugly into the U channel section that forms the bottom of the chassis so all AC will be confined to the lower back part of the chassis.
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I then installed the top of the chassis ready for preparing to mate up the rest of the chassis. I think it should look rather nice with the red and a nice hardwood front panel.
Hi Ray,
The chassis is looking great, really like the red, was that anodized or powered coating? The new chassis layout looks good too.
Did you finish the Sissy v3?
Jon
The chassis is looking great, really like the red, was that anodized or powered coating? The new chassis layout looks good too.
Did you finish the Sissy v3?
Jon
Hi Jon. The red is anodised. I'm building the SissySIT in parallel, switching between the projects as parts and inclination permit...
Is it stereo? Dual mono? Heat sink on each side of the case?
The choke right above the SITs may get quite hot.
The red is nice. 🙂
The choke right above the SITs may get quite hot.
The red is nice. 🙂
It's stereo Ben, there's another heatsink to bolt onto the open side and a second choke that mounts to the right of the one in the picture. I did wonder about having the chokes close to the SITs - I want to make the black channel section a complete follower module that could be exchanged if the need arises soI'll have to see how the heat goes - with large heatsinks and lots of vertical ventilation I'm hoping the temperatures are 'reasonable'.
I don't see where they claim "choke loaded"?
It looks to me like a common-mode choke for power noise reduction. Although I also wonder if the seller really knows what it is. (And language differences: 'red bull'??)
A common-mode choke "could" work if generously gapped. Normally we wire them so the DC currents in the two windings null, but that can't work as a choke-load.
You are quite right: these chokes are designed for power supply de-rippling.
The term Red Bull is because the origin of the advertisement is in Chinese and the translation is not very advanced (So, China becomes 'porcelain' here in my countrywell, because china tableware is made of that material.) The 'bull' probably is a type of core stacking, like EI.
You are perfectly right -- but it might be possible to use it in a SuSy configuration like here: SuSyLu Where Are You?
A bit more inductance would be nice, though.
I've been thinking on this and I'm looking at perhaps relocating the chokes to the rear panel. Hmmm!