[eddiewalker]

I don't have the money for a Millett Max, by any means, but I would love to try some "tube sound" through my MS2i's. I'm looking at the "SOHA" hybrid that floats mostly around Headwize. At under $100 estimated, it sounds like a good shot. Does anyone have any experience with the design, particularly with Grados?

 

[FallenAngel]

I don't think it'll really be any cheaper than the Millet Max with similar quality components. You would still be looking at shipping for 2 or 3 suppliers and I'm expecting both to run in the area of $160-$200 after shipping fees.

Of course, if you go with cheaper parts, you can probably manage to knock $30-$40 off that price, but I always think that if you build an amplifier that you will keep for months (in my case) or maybe even a year or more, the slightly higher initial investment will pay off in the end.

It's things like that which keep my wallet very unhappy with this site.

 

[Ech0]

You might want to look at Glass Jar Audio's website if you haven't already. I recently bought a level 1 SOHA kit from jeff and was happy with it. I made a couple of modest upgrades, but, that was all. There are a few things you need in addition to the kit. Someone else posted what they were here in the forums I think (or @ Headwize?). Edit: here it is-- http://www.head-fi.org/forums/showth...light=soha+kit

Here's the address:

http://glassjaraudio.com/categoryNav...g?categoryId=3

Ech0

 

[heatmizer]

Have to agree with the max is a bit better sounding with equivalent parts than the soha. The soha by no means sounds bad is really a nice sounding amp. Jeff's soha kit is top notch and with his couple upgrades is quite nice

 

[tomb]

Quote:

Originally Posted by heatmizer /img/forum/go_quote.gif Have to agree with the max is a bit better sounding with equivalent parts than the soha. The soha by no means sounds bad is really a nice sounding amp. Jeff's soha kit is top notch and with his couple upgrades is quite nice

That's a pretty big understatement, but rather than disparage another design, PM me if you want comparison details.

That said, I love the SOHA and have 4 boards populated in various stages of casework, with another 4 boards that I fully intend to populate sometime, too. The SOHA is a very, very fun amp. It can be built into a very compact package if you offload the transformer into a walwart enclosure (see some of Batman's posts in the orig. Headwize thread, or Amb's CKKIII build).

Tube rolling is an absolute blast and every 12AU7 variant you put in there has a different - but interesting - effect on sound quality. Opamps have an effect, too - but once I put an OPA2107 in there, I stopped rolling opamps. The same can be pretty much said for the GE 5963, but it's still a lot of fun to try other tubes.

One of the original design parameters was to keep the cost under $50, even with the toroid transformer. So, it can be an economical build if you don't go crazy on the caps and stay away from the Telefunkens and the 7316's.

 

[headphonejunkie]

My SOHA is just as good as my millett with diamond buffer bd and when the jisbos bds are avialable it will sound even better. I would go with the soha then upgrade it later.Plus you could try some telefunkens later or bugle boys if you reallly wanted. You can't do that with the millett max.

 

[mb3k]

There's some interesting drama on Headwize and these forums from the original design to the PCB - lengthy threads.
The Millett Hybrid (Max) and SOHA are both fun to make amps with tons of support (tomb, the documentation on the Max is outstanding).
There are many 12AU7 brands for the SOHA which may lure you to the amp...

 

[tomb]

Quote:

Originally Posted by headphonejunkie /img/forum/go_quote.gif My SOHA is just as good as my millett with diamond buffer bd and when the jisbos bds are avialable it will sound even better. I would go with the soha then upgrade it later.Plus you could try some telefunkens later or bugle boys if you reallly wanted. You can't do that with the millett max.

Again, I didn't intend to disparage the design. We completely agree with the potential of the SOHA, especially in the quality of the tube. Although, tube experts sometimes refer to the 12AU7 as "junk". I'd hate to see what they'd say about the Millett's car tubes: I don't think I want to know.

In any event, the SOHA is simply not as far along in the evolutionary cycle as the Millett. Whereas the MAX may represent as far as the Millett can achieve. If the Jisbos work out well, then maybe the SOHA can grow just as the Millett has.

 

[headphonejunkie]

When it comes to comparisons I think there are some differences that are not that big. In order to really tell the differences you would need an A/B test and then I am not sure there would be that big of a difference.I guess it depends on what you want.I think the soha is a entry point for higher level amps.It gives you the taste of what higher end tubes can give you. Look at Mcintosh amps they used the 12au7 tubes a lot.

 

[dsavitsk]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif Although, tube experts sometimes refer to the 12AU7 as "junk". I'd hate to see what they'd say about the Millett's car tubes: I don't think I want to know.

The reason people disparage the 12au7 is the same reason you guys like it. It has a lot of even order harmonic distortion giving it that vintage "tubey" stereotyped sound. When these were developed and used in amps in the 50's, designers would apply lots of feedback to tame down the distortion. Older, and newer tubes (that is, 1930's tubes and 1960's high Gm tubes) don't have this same level of distortion. Thus they don't need all the feedback, and thus to many of us sound better. For instance, you'll hear 6sn7 circuits described as sounding clearer than 12au7 circuits, even though they are electrically not that different.

 

[headphonejunkie]

I have read that the 12ax7 is even considered worse. I personally do not hear anything wrong when listening but I do not have any high end amps to compare it to. Though, I only spent a $150 not thousands.

 

[diego]

Do you guys consider that a soha would be a good first DIY project? I was thinking about it because I can get a kit for it but, are there any other kits that are easier to build?

Thanks in advance for your recommendations,
Diego

 

[Ech0]

I'm going to answer from the standpoint that I am fairly new to diy electronic projects, although, not a stranger to diy. My progression was this: CMOY >> CMOY (modded) >> SOHA. I had the least problems with construction of the SOHA due to purchasing the kit. But, I couldn't have built it successfully without doing the CMOY projects first. I'm certain of this. So...depends a bit on your background, but, I'd say there is a better "first choice".

I really like the SOHA and am assembling the parts for a Millet Hybrid Max board now. Caution: this hobby can be addictive and hazardous to you wallet.

 

[heatmizer]

The soha is easy to build.

 

[diego]

Thanks for the advice. This would be my second project but the first one was also a kit and many years ago. So, I think I'll start again with the soha.

Regards,
Diego