oneplustwo Aleph X build thread

[oneplustwo]

On the aleph vs f5 question, I don't really have enough to go off on. I've never done an AB comparison and I don't have a balanced source at the moment to take advantage of the balanced nature of the aleph x. (Getting an emotiva xda2 next time they go on sale... Sold my xda1.)

I will say that I do love the f5 dcb1 combo. The extra power of the aleph x is nice but I never really missed it before. Sound quality wise, it's a tough call without doing a real controlled comparison. And I am no authority on these things. In my mind, I build because I like to build. And if the sound is good, then I don't worry about the differences so much.

[Eric]

Interesting that you say you've "lost" your .1 system after moving to DIY. I was looking to make a small, but high quality, 2.1 system for either home or office. I'm debating between an F5 and ACA front ended by a DCB1 driving a set of DIY speakers and a 10" sub. From what I have read, others report the DCB1 has plenty of drive for dual outputs to an amp and a sub amp. I will run the two main speakers full range (they will probably be smallish bookshelf type) and get a good plate amp for a 10-12" driver. I'm aiming for a sealed sub with a small footprint.

[oneplustwo]

Confirmed with my Fluke 45 that AC ripple is about the same on both channels... about 17mV. I then measured with my new Agilent U1252A handheld DMM (thanks grenert!) and got only 0.5mV. Confused, I whipped out my new to me Tektronix 2465 scope (thanks again to grenert) to see what was going on and saw about 50mV peak to peak which I believe measures to 17mV RMS (Amplitude/sqrt(2)). So I guess bench top DMMs are truly better! And this Agilent DMM is no slouch.

Can someone verify my thinking here?

[oneplustwo]

Sounds like a good plan. I'm thinking about building my F4 for the office with a couple small TABAQ speakers. No need for a sub in the office!

I was going to buy a sub amp, but I was thinking about going cheap and using my chip amp as a sub amp. Just needed a way to get the crossover between it and the mains... thus the DCX2496 on the way to me from djdeals.com. I hope. They seem a little on the sketch side. We'll see.

Anyway, I figured this would also give me flexibility to try bi amping or some other sort of configuration in the future.

Originally Posted by Eric

Interesting that you say you've "lost" your .1 system after moving to DIY. I was looking to make a small, but high quality, 2.1 system for either home or office. I'm debating between an F5 and ACA front ended by a DCB1 driving a set of DIY speakers and a 10" sub. From what I have read, others report the DCB1 has plenty of drive for dual outputs to an amp and a sub amp. I will run the two main speakers full range (they will probably be smallish bookshelf type) and get a good plate amp for a 10-12" driver. I'm aiming for a sealed sub with a small footprint.

[Eric]

Originally Posted by oneplustwo

Confirmed with my Fluke 45 that AC ripple is about the same on both channels... about 17mV. I then measured with my new Agilent U1252A handheld DMM (thanks grenert!) and got only 0.5mV. Confused, I whipped out my new to me Tektronix 2465 scope (thanks again to grenert) to see what was going on and saw about 50mV peak to peak which I believe measures to 17mV RMS (Amplitude/sqrt(2)). So I guess bench top DMMs are truly better! And this Agilent DMM is no slouch.

Can someone verify my thinking here?

This sounds about right to me. The "typical" small, handheld DMM doesn't really provide the whole picture - many of them are great, but lack an RMS read. In my CRC, I can measure about 200mV on the first C, I drop about 1.7V across 0R2, and then I measure about 5mV on the last C. I'm running ~22v rails at about 8A bias. The funny thing is that bias changes (lowers) as the amp warms up.

Those 100w monoblocks get large and heavy in a hurry, huh? But they sure do sound nice!

[oneplustwo]

Yes, very heavy. I still have yet to weigh them, but I'm pretty sure they're close to 50lbs each. Maybe that will be my exercise tonight.

[Eric]

Originally Posted by oneplustwo

Maybe that will be my exercise tonight.

Ha- you're funny. A true DIYer is an obsessive compulsive tweaker. Such activities clearly extend beyond a single evening. Thus, you have several weeks of exercise before you (unless your work area isn't the middle of the living room floor after the kids are in bed).

Be careful, or we'll have to revoke your DIY license...

[oneplustwo]

I'm considering upgrading to jfet front end but I'm not sure I'm up to the task. Instead, I think I'll work on the 10 other projects in various states of completion. Anyone care to vote for F4 or penultimate Zen 4? They're next up. I also need a small speaker project to go with the F4. Was thinking tabaq or some other single driver design. Open to suggestions.

[Eric]

Upgrading the Aleph-X front end is my next project. I've just ordered some JFETs from Spencer and am waiting for them to arrive. Between these and others that I've picked up and matched on my own, I have enough for my Aleph-X amps, an F5 build, and a few DCB1 boards that I have. William and Graeme have been very helpful in helping me understand the process of replacing the 9610s with JFETs. As I begin the actual work, I'll update this section of my web page. Given all of the other things going on in life, this is likely to take another few weeks to months...

[6L6]

ZV4 or F4? Wow - those are two designs I really like... It's hard to choose!

The F4 can use your F5 PSU, so it's likely easier to make...

The ZV4 is an older design that hasn't had much attention in a long time -- It could probably use the love!