Yes, there are space enough in the chassis for a good PSU. It will be based on the DiyAudio Store standard PSU PCB and then probably an extra set of caps so it will be more like CRCRC than CRC. The magnetic "leak" should be less in a large transformer where you only use a small part of the core. At least it will stay cool and hopefully no mechanical noise.
I'm guessing this has been asked before, but I couldn't unearth it using the search function (I even searched for "graft" and "plumb") but is it possible to, um, graft or plumb the M2X input boards onto or into an existing M2? I'm thinking of the Norwood board that someone has lying around unused, because of the SMD aspect.
Is it possible? Sure. All you need to do is arrange some kind of mechanical support to hold the daughter card stationary, and then run four (4) wires between motherboard and daughter board: Output, Input, PosSupply, NegSupply. Naturally the shorter these wires are, the better. In M2X they are about 10-15mm long and that seems to work well.
Has someone already done this, and created a photo album showing exactly what they did from nine different angles? Not that I'm aware of. Check the Tea-Bag M2 Clone thread.
Has someone already done this, and created a photo album showing exactly what they did from nine different angles? Not that I'm aware of. Check the Tea-Bag M2 Clone thread.
Precisely the kind of handholding that I look for before I start a project! 😉
Thanks, Mark, I'll go to the swap meet section and post a WTB right now.
After some time now with the M2x broken in, four daughter boards (Norwood, Ishikawa, Mt View, & Tuscon) run through three sets of speakers, I am finally providing a review. The amp was run on Thiel CS2.3, Snell KII, and Triangle Comete speakers, no pre-amp and a variety of music sources, including records, and flac files via Hifi-Berry and iPhone. Here are my observations...
The Norwood produces tight bass, with a laid-back midrange and bright highs without any sharpness. Very lifelike live music with very good sound-staging and instrument separation.
The Tuscon is overall very balanced and relaxed. Instrument separation and soundstage was not as good as other cards. While there was nothing done wrong, it was the least engaging of all the options.
The Mt. View had the widest soundstage with very good instrument separation. Bass was tight and well defined. Live music was not as lifelike as the Norwood, but much better than the Tuscon. Midrange was very clear but took a back seat to open and bright highs which were sometimes too sharp for my ears.
The Ishikawa has excellent midrange and vocals with a big sense of space. Highs are bright and clean without being sharp. Bass is tight without any boomy nature. The soundstaging and separation is also excellent. Live recorded music seems to transport me to the source of recording.
For me the Tuscon is the least enjoyable, the Mt. View better but with a lack of life and too much sparkle came next. The Norwood took a close second, only edged out by the Ishikawa's super lifelike presentation and wide open soundstage.
I added the feet, baseplate and buttoned up the chassis tonight with the Ishikawa in place. I would like to thank everyone who helped with my build and journey.
The Norwood produces tight bass, with a laid-back midrange and bright highs without any sharpness. Very lifelike live music with very good sound-staging and instrument separation.
The Tuscon is overall very balanced and relaxed. Instrument separation and soundstage was not as good as other cards. While there was nothing done wrong, it was the least engaging of all the options.
The Mt. View had the widest soundstage with very good instrument separation. Bass was tight and well defined. Live music was not as lifelike as the Norwood, but much better than the Tuscon. Midrange was very clear but took a back seat to open and bright highs which were sometimes too sharp for my ears.
The Ishikawa has excellent midrange and vocals with a big sense of space. Highs are bright and clean without being sharp. Bass is tight without any boomy nature. The soundstaging and separation is also excellent. Live recorded music seems to transport me to the source of recording.
For me the Tuscon is the least enjoyable, the Mt. View better but with a lack of life and too much sparkle came next. The Norwood took a close second, only edged out by the Ishikawa's super lifelike presentation and wide open soundstage.
I added the feet, baseplate and buttoned up the chassis tonight with the Ishikawa in place. I would like to thank everyone who helped with my build and journey.
I appreciate very much your review. Thanks.
It's a bit anti-climatic that, after all the effort done here to provide alternatives to the 'unobtainable' Toshibas, they are still your choice... but it seems like a really insightful and thoughtful process, which I really appreciate.
Thanks!
Rafa.
It's a bit anti-climatic that, after all the effort done here to provide alternatives to the 'unobtainable' Toshibas, they are still your choice... but it seems like a really insightful and thoughtful process, which I really appreciate.
Thanks!
Rafa.
Sesquipedalio,
Thanks for sharing your listening impressions.
Have a question though - AFAIK the M2 is not a high gain amplifier (14dB?), so wouldn't a preamp with decent gain be a welcome addition in the system?
Thanks for sharing your listening impressions.
Have a question though - AFAIK the M2 is not a high gain amplifier (14dB?), so wouldn't a preamp with decent gain be a welcome addition in the system?
Thank you for confirming Jim.
My query was in response to Sesquipedalio's post where he mentions that no preamp was used when he did the listening tests.
- Zia
My query was in response to Sesquipedalio's post where he mentions that no preamp was used when he did the listening tests.
- Zia
Why not build and listen to the Austin input stage?
BTW some people reported a strong sonic preference when they compare [Tucson with OPA604(THT)] and [Tucson with OPA1611(SMD)]
BTW some people reported a strong sonic preference when they compare [Tucson with OPA604(THT)] and [Tucson with OPA1611(SMD)]
The M2 has 15 dB of gain. What gain preamp you need depends on your whole system. In my case, I have 103 dB+ horn speakers. I built a transformer coupled linestage with a 5.6:1 stepdown that provided only 6.7 dB of gain. This driving the M2 is perfect combo for my setup with the normal voltage inputs. I built another linestage (that used the same tube) but provided full mu of the tube or 19 dB of gain. It was too much gain for my system.
Milkduds,
You have a (very) high sensitivity speaker system! 🙂
Fully agree.
My question was addressed to Sesquipedalio, who in his post lists three speakers. The sensitivity according to Stereophile for his speakers are as follows:
Thiel CS2.3: 87dB/2.83V/1m
Snell KII: 90dB 1W/1m (anechoic)
Triangle Esprit Comete Ex: 90dB/W/m
Decent sensitivity, but not in very high; hence my assumption was that some preamp gain would help.
You have a (very) high sensitivity speaker system! 🙂
Fully agree.
My question was addressed to Sesquipedalio, who in his post lists three speakers. The sensitivity according to Stereophile for his speakers are as follows:
Thiel CS2.3: 87dB/2.83V/1m
Snell KII: 90dB 1W/1m (anechoic)
Triangle Esprit Comete Ex: 90dB/W/m
Decent sensitivity, but not in very high; hence my assumption was that some preamp gain would help.
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According to the manual, the M2 yields 1W@500mV in, and needs 3V in for rated power. So a few dB of preamp gain would be helpful for many of us.
Attachments
Thanks Mark! I had not downloaded the manual. Makes more sense now.
BTW, the 15 dB came from Nelson's table at the FW site.
BTW, the 15 dB came from Nelson's table at the FW site.
I guess the best way is to switch SWMBO into HWMBO. She has the kitchen for playground and even electronic tools....hoven, iron, vacuum cleaner...isn't enough ? 😛😛
That’s why the default 16.7dB of gain in the Melbourne front end can come in handy. You can of course, adjust the resistors to get whatever gain you like, such as 6dB etc.