10F/8424 & RS225-8 FAST / WAW Ref Monitor

Founder of XSA-Labs
Joined 2012
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It depends on how loud you listen. These are 82.4dB sensitive at 2.83v and 1m. I like to have at least 40w rms - but that’s just me. If you like the sound of tube amps, consider a tube preamp driving a low distortion SS amp. It will do whatever the tube asks it to do, including, sound like a tube :)

If 85dB is loud enough for you, then that’s 2w, leaving you with 9dB of headroom for peaks.
 
Founder of XSA-Labs
Joined 2012
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I cleaned up the amp display area in my lab using a shelf. Now all active amps can be accessed and connected in an instant. I have a Furman 8 tap linear multi-tap AVR toroidal power conditioner on the bottom rack. I also got a couple of mew amps to evaluate. My first tube amp, a Line Magnetic 211ia. I was very pleasantly surprised to learn that it can drive the big TLs just fine (32w into 8ohm ultra linear mode).
955664d1622265345-bench-tonight-obt-bbfb706b-de11-41ce-a404-4b4413108d89-jpeg


The tube amp also has a nice trick when you dim the lights too:
955665d1622265347-bench-tonight-obt-dd349a01-639a-4d42-8aa5-7a1e52951377-jpeg


This is my very first transformer output coupled tube amp. I must say, it’s very pleasant and I can see then allure folks have with tube gear. It is very different then SS amps. The good news is that the impedance of the 10F/RS225 TLs appears to be very compatible with an EL84 push pull amp.
 
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X,

Kudos on your new rack / shelf setup - it's very functional and survives your continuous R&D efforts well.

Whatever can be gleaned from the video, their is plenty of low frequency output with the LuFo amplifier in your system, and the bass sounds well articulated. Of course, the full extent of the playback quality is difficult to discern over a YouTube video, and I suspect that the actual listening experience will be much more pleasurable. :)

Again, great work and a big thanks to JPS64 for getting a superb PCB design done for the DIY community. Look forward to folks starting to build this amp.

I myself have this amp on my shortlist of builds... but we only have MOTs made for 230V AC line voltage, and these have a far higher DC resistance vs what you get with 110V mains line MOTs. So will have to wait and consider the best course of action (custom chokes or other options). In the meantime will be enjoying the developments and impressions from the community.
 
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Hi,

i'd love to have your listenning room XRK with so much amp to compare and listen !

for now, i'm in painting and it take a long time:(

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i just received the last part of the crossover and i'll do them this week!

i hope they will sing in 10 days !

ps: the rockville are nearlly finished too !
 
My first tube amp, a Line Magnetic 211ia. I was very pleasantly surprised to learn that it can drive the big TLs just fine (32w into 8ohm ultra linear mode).
This is my very first transformer output coupled tube amp. I must say, it’s very pleasant
well on tube world is a lot of power as tube have soft clipping , pentode IDHT in push pull with feedback ,must try SE DHT triode no fb like 300b or 211 ....;)
as PP 2A3 dht triode no fb or nice 6v6 in triode mode
 
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Ok, a question for the collected woodworkers on this thread...

How many of you used simple butt joints on the wood and how many did rabbets/dadoes for the joining surfaces? Have any of the butt joints had issues, or is that method (butt joints, glued and clamped) proven sufficiently strong to hold it together? I have done these kinds of joints in all kinds of wood for shelving and other projects, so doing it isn't a problem, I'm just not sure how helpful it would be (and I know it will be a bit of a pain to execute).

I'm trying to layout all the panels and determine how many 60" square sheets of the Baltic (13 ply in this case) will be required, but it will be different depending on the joinery I use.

In short, is the fancy joinery necessary or even worth the effort? Please post your opinions, observations and thoughts. And, as always, thanks for the insight!
 
Simple butt joints are way strong enough if your wood is precisely cut and you use modern glue -- lots of PVA or a more judicious amout of urethane. I use a plate jointer with biscuits to hold alignment, and that stops most sliding problems. Harbor Freight sells one cheap that works well as long as you don't try to do anything fancy. Fancier joints from miters on up look very nice and may be stronger, but well done butt joints are strong enough. Caulk the joins internally for a belt-and-suspenders approach to sealing.

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Hi All,
I'm keen to build the TL version of this design but have 3 questions on the physical build - my first TL build.

1/ Don't see any baffle edge roundover on peoples cabinets - is there a reason for this ?

2/ Haven't noticed any corner bracing along outside panel internal edges - would the area of the bracing be sufficient to throw out the required pipe cross section calcs ? (don't have a feeling for the design sensitivity to this)

3/ Have read that cabinet stuffing is fairly critical on TL boxes. Is there any detail posted on the recommended stuffing approach for this design ? (I'd normally use auto panel deadener, egg crate foam & poly fibre - but unsure of where & how much in a TL box)

Thx in advance.