You asked for a 2A3 monoblocks kit like this a few months ago, and we have delivered!
https://bottlehead.com/product/mon-amour-2a3-monoblock-amps-kit/
https://bottlehead.com/product/mon-amour-2a3-monoblock-amps-kit/
MonAmour, our new premium 2A3 monoblocks kit
- Thread starter Doc B
- Start date
Yes indeed, they are. The meters should give a pretty good indication of when the 300Bs are worn out, as well as confirm the current switch setting.Gerry E. said:
Karl5150
New member
Looking (drooling) at the in-depth info on the product page I see that even at the lower operating point the MonAmours put out an additional watt/channel (22%) over the StereomourII. Is this due to the use of the up-spec PCs and OTs, or are there other circuit changes that also play into the improved output?
(Voice in my head: "Back away from the order button, you already have more BH amps than sources.")
Karl
(Voice in my head: "Back away from the order button, you already have more BH amps than sources.")
Karl
It's a combination of a different operating point and the different iron that provide a bit more power compared to the Stereomour at the 50mA operating point. At 60mA, we are fully taking advantage of that beefy iron.
My order is in. I thought the Kaiju might be the last amplifier I'd need to to build, but I enjoy building the kits and have to do it just to see how it sounds with the Zu Soul Supremes. I don't have space for another system, so I may seriously think about selling the Kaiju to let someone else enjoy it once the MonAmours are built
There will be some fun modifications available for this kit that just aren't doable with the Stereomour or the Kaiju. I have to order some bits and pieces that I don't have sitting around to evaluate these changes, but the flexibility offered by the simpler DC filament supply opens up some interesting choices.
It really depends on what you're looking for. The Kaiju eeks out a tiny bit more power, though certainly nothing you're going to notice. It's also a little bit quieter, but we have used noisier amplifiers on headphones before and not noticed that issue either, so that's not exactly a point in either favor.
The Kaiju is a bit less expensive but comes with lower quality parts. You could certainly upgrade those later on your own, and there is (barely) space to fit them in the amp. With the Kaiju, you will be married to the 300B output tube, which I don't think is a problem myself. I would say the Kaiju is a little easier to build overall. The form factor may also be more convenient for many, as it is a proper width to just take up one shelf on a stereo rack. The MonAmours are surprisingly large in comparison.
The MonAmours are a bit more expensive (we'll ignore the introductory sale thing) but offer film cathode bypass caps, some nicer coupling caps, and some nice cosmetic touches. The very deep low bass will be slightly better defined based on the altered operating point allowing us to use the full winding on the choke, but the Kaiju is already fantastic in this department. You will get the convenience of being able to use 2A3s right off the bat and the 2A3-40, which is really a 300B with its filament connected differently so it will run on 2.5V. I have been running the first pair for a few weeks now, and going from a Sovtek 2A3 to a JJ 2A3-40 and using the switch to adjust the current really does alter the amp from a 2A3 amp to a 300B amp sonically. There is also certainly the potential to modify the MonAmour to take 300Bs, and I hope to use the amp we built for the manual photo shoot on Sunday to perform these experiments.
I could definitely be happy with either amp, and I'm certainly satisfied having both around. My collection of 2A3s is far larger than my collection of 300Bs though, and some of those old stock 2A3s sound pretty nice. I also admit that I really like shrouds and meters. If cosmetics aren't much of a consideration and you're only ever going to run 300Bs, I'd stick with the Kaiju.
The Kaiju is a bit less expensive but comes with lower quality parts. You could certainly upgrade those later on your own, and there is (barely) space to fit them in the amp. With the Kaiju, you will be married to the 300B output tube, which I don't think is a problem myself. I would say the Kaiju is a little easier to build overall. The form factor may also be more convenient for many, as it is a proper width to just take up one shelf on a stereo rack. The MonAmours are surprisingly large in comparison.
The MonAmours are a bit more expensive (we'll ignore the introductory sale thing) but offer film cathode bypass caps, some nicer coupling caps, and some nice cosmetic touches. The very deep low bass will be slightly better defined based on the altered operating point allowing us to use the full winding on the choke, but the Kaiju is already fantastic in this department. You will get the convenience of being able to use 2A3s right off the bat and the 2A3-40, which is really a 300B with its filament connected differently so it will run on 2.5V. I have been running the first pair for a few weeks now, and going from a Sovtek 2A3 to a JJ 2A3-40 and using the switch to adjust the current really does alter the amp from a 2A3 amp to a 300B amp sonically. There is also certainly the potential to modify the MonAmour to take 300Bs, and I hope to use the amp we built for the manual photo shoot on Sunday to perform these experiments.
I could definitely be happy with either amp, and I'm certainly satisfied having both around. My collection of 2A3s is far larger than my collection of 300Bs though, and some of those old stock 2A3s sound pretty nice. I also admit that I really like shrouds and meters. If cosmetics aren't much of a consideration and you're only ever going to run 300Bs, I'd stick with the Kaiju.
We provide tubes with the kit, which are generally American old stock 5670s and Sovtek 2A3s.
-PB
-PB
Awesome!triode said:
We shot the photos for the manual on the 10th, and the manual writing process usually takes some weeks, so it will be a little while longer before the manual is ready.
Microphonics are visible on an oscilloscope, but not something I've been able to hear with any of the 5670 driven amps we have put out.
Hi Paul
I notice that the parafeed caps is big (12uF !!) compare to usual 3-5uF.
If I want to substitute this, would 10uF sufficient? or should I go for 15uF? 12uF is rather hard to get.
Also what is the interstage coupling cap value?
I guess the 400V would be minimum rating for both coupling caps?
I'm in the mood for Christmas shopping here and already thinking of upgrade caps !!
Thank you very much
I notice that the parafeed caps is big (12uF !!) compare to usual 3-5uF.
If I want to substitute this, would 10uF sufficient? or should I go for 15uF? 12uF is rather hard to get.
Also what is the interstage coupling cap value?
I guess the 400V would be minimum rating for both coupling caps?
I'm in the mood for Christmas shopping here and already thinking of upgrade caps !!
Thank you very much
Paul Joppa
Moderator
The calculated value is 13.3uF, so 15uF is closer - but 10uF will work. The difference is unlikely to be audible, and if it is, it will be more a function of the speaker than the cap per se.
I do not recommend a voltage rating less than 600v for either cap. Interstage is 0.10uF.
I do not recommend a voltage rating less than 600v for either cap. Interstage is 0.10uF.
