I have for some years followed the restoration of the Boardwalk Hall organ in Atlantic city. I think about 20.000 pipes out of the 33.000 is now playing. The problem is to make a recording and play-back. It has a 18m pipe (1500 kg) which resonates at 8 Hz. It can only be felt. So you need to be there. It could be fun some day. The electrical engines that produces the air pressure is quite amazing. Everything in this organ is amazing. It goes very deep 🙂 .....but recording I have heard so far sounds "muddy". I guess it is a challenge to make a recording from such an instrument. But a good test for Norwood 🙂
Very cool. I like Victor Wooten. He is fun to watch. The Oregan video is really neat.
I have a question for the people who have tried the M2 and the F6. Is the bass comparable between the two?
I have a question for the people who have tried the M2 and the F6. Is the bass comparable between the two?
'no bass' <- I mean that it is 'not bassy' than other boards.
It can't be possible 'NO' bass.
Anyway, I'll try again.
It can't be possible 'NO' bass.
Anyway, I'll try again.
My F6 has a more extended and articulate bass response than my M2x. Both have the Austin input stage. My F6 uses FQH44N10 Mosfets and the M2x uses IRFP240 and IRFP9140 Mosfets.
Because of the modifications I’ve made to the F6, it is certainly possible that others may have different impressions of the two amps. I built my F6 specifically to drive my old Vandersteen 2C speakers. I recently replaced the 2Cs with 3A Signatures, so the comparison will be performed again. The M2x is currently doing a very fine job.
Because of the modifications I’ve made to the F6, it is certainly possible that others may have different impressions of the two amps. I built my F6 specifically to drive my old Vandersteen 2C speakers. I recently replaced the 2Cs with 3A Signatures, so the comparison will be performed again. The M2x is currently doing a very fine job.
Yes. I remember you mentioning your F6. It has higher voltage rails as well doesn't it?
I'd be interested in the results of your redoing the experiment with the 3A. I had a pair of 2CI's that I powered with a f6. It did pretty darn well considering. However, I will say that the 2ci's are some of the most difficult speakers that I have powered with that amp.
Those 3a's are supposed to be wonderful speakers. I hope that you are enjoying them 🙂
I'd be interested in the results of your redoing the experiment with the 3A. I had a pair of 2CI's that I powered with a f6. It did pretty darn well considering. However, I will say that the 2ci's are some of the most difficult speakers that I have powered with that amp.
Those 3a's are supposed to be wonderful speakers. I hope that you are enjoying them 🙂
Yes, my F6 has a dual-mono supply which delivers +/- 26V. It is currently on my work bench as I re-check the bias current. The M2x was also recently rebuilt with a dual-mono supply that delivers +/- 20V.
The 3As are a joy to listen to. They have me sitting through whole albums, demanding my full attention to the music.
The 3As are a joy to listen to. They have me sitting through whole albums, demanding my full attention to the music.
Yes, the M2x originally had a shared supply (single 400VA toroid) at 18V. The rebuilt supply has dual 200VA toroids with synchronous rectifiers, and just hits 20V.
The rebuild was very worthwhile.
The rebuild was very worthwhile.
Interesting. So What I am understanding is that you have 20vdc rails. That is much lower than the original. What are you trying to gain with the lower voltage?
The original FirstWatt M2 (father of the M2x) that was sold to paying customers, had +23VDC and -23VDC supply rails.
The actual first M2x ever built (now found in the rack of my AV room) has approx plus/minus 22VDC rails, thanks to an Antek AS-4218 toroidal transformer and Fairchild FFPF30UP20S very-soft recovery rectifiers. Works great with UMS spec heatsinks, 4U/300.
The actual first M2x ever built (now found in the rack of my AV room) has approx plus/minus 22VDC rails, thanks to an Antek AS-4218 toroidal transformer and Fairchild FFPF30UP20S very-soft recovery rectifiers. Works great with UMS spec heatsinks, 4U/300.
I was wrong before. The number I was remembering was the 400VA transformer secondary voltage. My M2x is currently running at 24V. The new power transformers are 250VA Triads that run a little hotter through the LT4320 based rectifiers.
My F6 is using a pair of dual rail SLB CapMx boards. The power transformers are Antek 300VA with 22V secondaries. Rail voltage is a little over 26V, and I have a set of Kemet 24,000 uF capacitors on the outputs of the SLB boards.
My F6 is using a pair of dual rail SLB CapMx boards. The power transformers are Antek 300VA with 22V secondaries. Rail voltage is a little over 26V, and I have a set of Kemet 24,000 uF capacitors on the outputs of the SLB boards.
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Hi All,
Possibly a little OT - if so, please let me know.
In complete contrast to the beautiful work in photos above, here's the temporary rat's nest I have just finished to try the Cedarburg cards as a buffer preamp, in the style of the B1. Works just fine; I'm listening to it now and it sounds pretty good at first hear, so to speak.
Pretty much everything except for the parts on the buffers themselves is recycled from my junk box or from old abandoned boards. PSU is a 24V EI with centertap, followed by a CRC (pay no attention to the extra resistors) and then a version of juma's "Easy-Peasy" Cx, built with whatever I could find lying around and not really adhering to the original values. Gives about +/-20.5V, which I could tweak up a little easily enough if I wanted to, I guess. Wiring is obviously not done with any attention to detail, just hooked up to see if things work OK, which they definitely do.
Next thing to try is output transformers, in the style of ZM's Iron Pre. I have a pair of Edcor XS440 I got cheap that should be entertaining. That may really be getting too OT, though, so perhaps I should post that in a different thread.
Possibly a little OT - if so, please let me know.
In complete contrast to the beautiful work in photos above, here's the temporary rat's nest I have just finished to try the Cedarburg cards as a buffer preamp, in the style of the B1. Works just fine; I'm listening to it now and it sounds pretty good at first hear, so to speak.
Pretty much everything except for the parts on the buffers themselves is recycled from my junk box or from old abandoned boards. PSU is a 24V EI with centertap, followed by a CRC (pay no attention to the extra resistors) and then a version of juma's "Easy-Peasy" Cx, built with whatever I could find lying around and not really adhering to the original values. Gives about +/-20.5V, which I could tweak up a little easily enough if I wanted to, I guess. Wiring is obviously not done with any attention to detail, just hooked up to see if things work OK, which they definitely do.
Next thing to try is output transformers, in the style of ZM's Iron Pre. I have a pair of Edcor XS440 I got cheap that should be entertaining. That may really be getting too OT, though, so perhaps I should post that in a different thread.
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I'll post anything that's interesting enough... Hope this meets the bar: a plot from REW for the right channel (I didn't measure the left). Input as close as I could get to 1V, volume set around where I would usually expect to have it in use. Not too shabby, I'd say, considering the minimal effort put into the PSU and wiring...
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As requested, here are a couple of photos of the next stage in my experiment. I've hooked up the Edcor XS4400 wired as an eight step AVC on the output of the Cedarburg boards. Again, a lot of this stuff is from my junk box (pile?) including the short ribbon connectors I used to wire the rotary switch. These turned out to be rubbish inside, although the poor soldering is at least in part due to my impatience. They work, though. I've kept the volume pots on the input for the time being, following a conversation with Zen Mod on this question in this other thread. I'll try to keep posts about the AVC in the other thread, not to go off topic too badly here.
Great fun, and it sounds good. Although admittedly it looks like a dog's breakfast...
Great fun, and it sounds good. Although admittedly it looks like a dog's breakfast...
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I have to say I’ve misunderstood about bass of Norwood.
Norwood has a full amount of bass but thick or heavy bass.
As I mentioned, the soundstage is narrow then all energy is center-vertically stacked. I fill some big and thick mass in the center somewhere and some thick curtain in front of me.
My system is a near field PC(desk)-fi and speakers are toed in.
I tried to make the speakers a little bit more straight and then …
a little wider soundstage, the big and thick center mass becomes smaller and the curtain also becomes thinner.
And I tried to change the output of DAC from raw output (just I/V conversion. 1.4Vrms 625 ohms) to buffered output with OPA1678 (2Vrms 10 ohms) and then the center mass and curtain have disappeared …. GONE!!
…..and the characteristics of Norwood are also GONE!!
I don’t know why.and what makes this happen.
I’m in a complicated, complex and confusing situation now.
I want to go back to IPS6 in a short time.
A simple and fast thing to try…
Attach the speaker cables reversed. Red to black at the amplifier. Reverse the speaker phase.
Report back with your sound impressions
Attach the speaker cables reversed. Red to black at the amplifier. Reverse the speaker phase.
Report back with your sound impressions
I checked all connections from dac, preamp, poweramp to speakers.
Each RED to RED and BLACK to BLACK.
....and tried the connection as 6L6 metioned.
speaker RED to amp BLACK and speaker BLACK to amp RED.
.... and the center mass gone, wide soundstage, sound becomes natural.
... and all sounds of songs are similar.
What is problem? Is the raw output from DAC is not proper? or something?
Each RED to RED and BLACK to BLACK.
....and tried the connection as 6L6 metioned.
speaker RED to amp BLACK and speaker BLACK to amp RED.
.... and the center mass gone, wide soundstage, sound becomes natural.
... and all sounds of songs are similar.
What is problem? Is the raw output from DAC is not proper? or something?
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There is nothing wrong.
At some point, something in your system is inverting absolute phase, and you’ve put it back to ‘normal’.
Inverting phase at the speakers is the easiest and simplest place to try changing it.
The fix is merely to try both connections with the speakers and listen to them in the way that sounds best to you.
😎
At some point, something in your system is inverting absolute phase, and you’ve put it back to ‘normal’.
Inverting phase at the speakers is the easiest and simplest place to try changing it.
The fix is merely to try both connections with the speakers and listen to them in the way that sounds best to you.
😎