Hello Meper,
nice to hear from you! Hope all is fine?
To your question: the 'Ishikawa' - board is very good and musical. For my taste perhaps sometimes a 'smoother'.
In my opinion, this can be very good with loudspeakers, which do a lot in the higher frequencies. Some members here use horn-speakers.
Most of my speakers are on the 'neutral' side. One pair of speakers slightly reserved in the highs. Nothing is missing.
If I change to my actively driven 2-way speakers (with air - motion - transformer), this can significantly change. The spl-curve of the AMTs goes
up above 8 kHz.
But these are the loudspeakers - not the input-boards of the M2X.
The newer boards like 'Cedarburg' and 'Milpitas' are in my opinion 'other animals'. I see also 'Norwood' in this range.
And I am not afraid of decoupling - caps. Use good ones.
If I remember right, then you use open-baffle-speakers? I would give the 'Ishikawa' - board for sure a try. Perhaps it will be 'audio - nirvana' in your setup?
And you know - the good old Toshiba- JFets are stll excellent devices.
And yes, I made an 'input - board - switcher' in my M2X. But I never switch during amplifier is in 'on' - status.
There are similarities between the 'Iron Pre' from ZenMod and the M2X with Ishikawa. Inputstage - transformer - outputstage.
Iron Pre is extremely detailed and 'clear' in the highs - in my setup.
I have 'Cinemags' in my Iron Pre - perhaps also influencing that -very personal- impression.
I think you will be forced to solder an 'Ishikawa' - board and try it in your setup?
If you haven't tried one of the OPAmp - based boards from Mark Johnson - you should give them/ one a try...
And as always: it depends on the whole chain - how it sounds. Every chain - link has its influence.
Cheers
Dirk
nice to hear from you! Hope all is fine?
To your question: the 'Ishikawa' - board is very good and musical. For my taste perhaps sometimes a 'smoother'.
In my opinion, this can be very good with loudspeakers, which do a lot in the higher frequencies. Some members here use horn-speakers.
Most of my speakers are on the 'neutral' side. One pair of speakers slightly reserved in the highs. Nothing is missing.
If I change to my actively driven 2-way speakers (with air - motion - transformer), this can significantly change. The spl-curve of the AMTs goes
up above 8 kHz.
But these are the loudspeakers - not the input-boards of the M2X.
The newer boards like 'Cedarburg' and 'Milpitas' are in my opinion 'other animals'. I see also 'Norwood' in this range.
And I am not afraid of decoupling - caps. Use good ones.
If I remember right, then you use open-baffle-speakers? I would give the 'Ishikawa' - board for sure a try. Perhaps it will be 'audio - nirvana' in your setup?
And you know - the good old Toshiba- JFets are stll excellent devices.
And yes, I made an 'input - board - switcher' in my M2X. But I never switch during amplifier is in 'on' - status.
There are similarities between the 'Iron Pre' from ZenMod and the M2X with Ishikawa. Inputstage - transformer - outputstage.
Iron Pre is extremely detailed and 'clear' in the highs - in my setup.
I have 'Cinemags' in my Iron Pre - perhaps also influencing that -very personal- impression.
I think you will be forced to solder an 'Ishikawa' - board and try it in your setup?
If you haven't tried one of the OPAmp - based boards from Mark Johnson - you should give them/ one a try...
And as always: it depends on the whole chain - how it sounds. Every chain - link has its influence.
Cheers
Dirk
Hi Dirk
All fine!
Thank you for the description!
Ishikawa is nice.
My M2X mono blocks have Cedarburg installed at the moment.
My current setup is Iron Pre SE + Lazy Bush mono blocks. DAC used in preamp mode (digital vol. control) so Iron Pre is implemented without pot. This would be quite similar to M2X just driven my DAC (DAC -> buffer -> step-up trafo -> source follower).
I have future plans for the M2X mono blocks. I have got a "rail set" to upgrade chassis from self threading screws to M3 screws.
Next project will be to build the Iron Pre BAL (without pot) as mono blocks and place them close to Lazy Bush followers using short RCA cables (longer XLR cables from DAC).
Trying M2X mono blocks in the future using just DAC as preamp I wonder how difficult it would be to modify a M2X input board to use DAC XLR out. Many M2X input boards use opamps as input and those are by nature differential. A unity gain differential buffer input board should not be that hard to implement for M2X?
I place my mono blocks close to speakers to have short speaker cables. Then I can save using Nordost Valhalla speaker cables! ....I can use 30 cm banana plug lab test cables instead! you can buy quite good speakers instead 4-5m set of Valhalla......
/Max
All fine!
Thank you for the description!
Ishikawa is nice.
My M2X mono blocks have Cedarburg installed at the moment.
My current setup is Iron Pre SE + Lazy Bush mono blocks. DAC used in preamp mode (digital vol. control) so Iron Pre is implemented without pot. This would be quite similar to M2X just driven my DAC (DAC -> buffer -> step-up trafo -> source follower).
I have future plans for the M2X mono blocks. I have got a "rail set" to upgrade chassis from self threading screws to M3 screws.
Next project will be to build the Iron Pre BAL (without pot) as mono blocks and place them close to Lazy Bush followers using short RCA cables (longer XLR cables from DAC).
Trying M2X mono blocks in the future using just DAC as preamp I wonder how difficult it would be to modify a M2X input board to use DAC XLR out. Many M2X input boards use opamps as input and those are by nature differential. A unity gain differential buffer input board should not be that hard to implement for M2X?
I place my mono blocks close to speakers to have short speaker cables. Then I can save using Nordost Valhalla speaker cables! ....I can use 30 cm banana plug lab test cables instead! you can buy quite good speakers instead 4-5m set of Valhalla......
/Max
You and your circuit designer will need to confront the disappointing reality that M2x motherboards and daughterboards, communicate to each over using FOUR electrical connections (bolts in fact).
They are: (1) Supply_Neg ; (2) Input_single_ended ; (3) Supply_Pos ; (4) Output_single_ended
Perhaps you can dream up some sort of clever multiplexing or Phantom Power (like "Power Over Ethernet") schemes, . . . ? Because, at first glance, it seems that you might also need (?5?) Input_other_half ; and perhaps (??6??) Output_other_half.
However, a devastatingly brilliant idea may occur to you and your team, which allows you to achieve everything you want using only four bolt holes. Good wishes for great success!
They are: (1) Supply_Neg ; (2) Input_single_ended ; (3) Supply_Pos ; (4) Output_single_ended
Perhaps you can dream up some sort of clever multiplexing or Phantom Power (like "Power Over Ethernet") schemes, . . . ? Because, at first glance, it seems that you might also need (?5?) Input_other_half ; and perhaps (??6??) Output_other_half.
However, a devastatingly brilliant idea may occur to you and your team, which allows you to achieve everything you want using only four bolt holes. Good wishes for great success!
In-, in+ from XLR directly to input board diff amp and not using input at main amp board?
Gnd could still be connected from XLR to Gnd at main amp board?
I must admit not much thinking.......just a "wild shot"........from my and my "team"
Probably Gnd needed at input board also to be able to make proper Rin........I guess.......
Not impossible to implement? .......or "mission impossible"?
Gnd could still be connected from XLR to Gnd at main amp board?
I must admit not much thinking.......just a "wild shot"........from my and my "team"
Probably Gnd needed at input board also to be able to make proper Rin........I guess.......
Not impossible to implement? .......or "mission impossible"?
Maybe the DIY FE 2022 can be used if mounted externally (e.g. at the M2X back panel). FE 2022 can be implemented as a unity gain buffer and has diff. input (in-, in+). If R5 is set to 0 ohm then it may be able to drive the Edcor?
Then on M2X main amp board a wire has to go from in to out at the bolts.
Then on M2X main amp board a wire has to go from in to out at the bolts.
@amandarae Is it really as easy as you've instructed here? I am closing in on M2X build completion starting with Ishikawa. I had contemplated deleting RV1 thinking I didn't have the equipment to properly calibrate, but your post here indicates just two DVM's required to set RV1 (or one if you patiently iterate). Thanks folks in advance for your insight.
What does it mean? I have a balance version, still in the box unopened and I have no access to it at this time so I do not know what's inside. Thanks!
instead of the 😉My M2x amp boards are nearly complete. DIY store UPS done. Antek 4218 with steel shield due to arrive this week.
Prevailing on you all here for advice on which case to order for a single stereo amp with PS in the case.
I'd like to balance goals of (1) reasonable size footprint (2) quiet (3) dissipation (4) pre-drilled and tapped UMS heatsinks.
Thanks!
Prevailing on you all here for advice on which case to order for a single stereo amp with PS in the case.
I'd like to balance goals of (1) reasonable size footprint (2) quiet (3) dissipation (4) pre-drilled and tapped UMS heatsinks.
Thanks!
My M2x was the first amp I built where I drilled and tapped the heatsinks myself. It actually wasn't difficult, once I realized the best method for me was to draw a drilling template on paper, tape that paper to the heatsink, then use a center punch to make a "divot" at the exact center of each hole. Now I can use the divots to position the drill bit precisely. Easy!
M2x amp boards, Ishikawa daughter boards and power supply are complete. Edcor autoformers fulfilled in ten days from website order using lowest cost shipping. Antek 4218 with steel shield arrived USPS in five days. Recognition due to Audiobear, his Milpitas boards are stellar and I have the all the bits ready to build those. I have a Simpson A24 bracket on the way to mount the Antek (a non-sequitur, I met the founder Barclay Simpson ~ 1986 a super nice person).
Another fine member here is provisioning an unused chassis, once that lands it shouldn't be long til I can compare to the Aleph J.
Thank you all for your support and informative posts. Check out "Soldier Field"
Another fine member here is provisioning an unused chassis, once that lands it shouldn't be long til I can compare to the Aleph J.
Thank you all for your support and informative posts. Check out "Soldier Field"
@Mark Johnson Thanks for the credit for mailing you a board but I like to think of them as Mark Johnson's boards. He provided the file. All I did was attach it to an order on-line. So we all need to thank Mark for making it not only easy to get one but for designing Milpitas in the first place. Edit: your boards look great!
I'm just starting to put mine together today. Should be testing/listening tomorrow.
I'm just starting to put mine together today. Should be testing/listening tomorrow.