I'm wondering if there is a Pass amp that can be reasonably easily DIYed and used to drive Magnepan speakers (for comparison I've built a chip amp, a simple transistor SE amp and a few SE and PP tube amps - nothing really complex though). I am considering some Maggies (1.6, .7 or lower end) and understand they are generally considered power hungry and needy of current, but I don't understand the mechanisms involved. Note that my space is fairly big with roof rafters as ceiling (sloped and up to 15' high or so).
I have an NAD amp that blew one channel and the output board appears to be shot, so I may gut it and use the chassis and a few key items if appropriate (PS transformer, perhaps the PS board). I'm looking at DIY options and thought I'd ask here if there's a DIY Pass amp that would fit the bill. Anyone have any experience with Maggies and Pass amps? If not, any suggestions where to find an amp that might work well? While I understand tube amp basics, transistors amps are harder for me to grok, though I can build from a recipe.
I have an NAD amp that blew one channel and the output board appears to be shot, so I may gut it and use the chassis and a few key items if appropriate (PS transformer, perhaps the PS board). I'm looking at DIY options and thought I'd ask here if there's a DIY Pass amp that would fit the bill. Anyone have any experience with Maggies and Pass amps? If not, any suggestions where to find an amp that might work well? While I understand tube amp basics, transistors amps are harder for me to grok, though I can build from a recipe.
Wait. Shhh, do you smell that ?
I can hear the 'Greedy boys' forming a stampede to the bench already
Thanks, Nelson. I took a quick look and skim through your article and while it's well described, even for a novice like me, it would take me some time to fully digest and a lot more to build. I don't see any evidence of a pcb, making it that much harder. But if it's a good option, I imagine I could work my way through it. Intrigued by the idea of a fix though... I'm also thinking about tube amp solutions, but my sense is that might be trickier. Maybe a hybrid?
Btsd, that's interesting. I'm not convinced that those who talk about 400wpc requirements for Maggies know what they are talking about. Magnepan says the most important issue is current and design, e.g. doubling of power with halving of load impedance, and that makes sense to me. But while I can believe a 30wpc tube amp could drive Maggies, I'm surprised to hear the Aleph J (at 30wpc, correct?) does a good job. Wish we were closer and I could have a listen!
Someone recently approached me about an F6 (25w @ 8 ohm, 40w @ 4ohm) for 1.3s.
The Maggies are 4 ohm and rather flat in the ohm vs freq range. Maggies are 86 db efficient. It just so happens I picked up a pair of Sonus Faber Concertos (SB) that are 86 efficient and around 6 ohm nominal based on Martin Colloms testing in Stereophile.
In a small area it was enough output. The F6 ran hot with Concertos. Hotter than with my 8 ohm, 90 db efficient DIY speakers. It sounded fine, but I believe more power would have been better, drawing out more from the SB monitors. Eventually will try my F5T v2 (50w), but it's out on loan. I think the same would happen with the Maggies. More power might draw out more detail and control them better.
Just my observations. Take them for what they're worth to you.
Vince
The Maggies are 4 ohm and rather flat in the ohm vs freq range. Maggies are 86 db efficient. It just so happens I picked up a pair of Sonus Faber Concertos (SB) that are 86 efficient and around 6 ohm nominal based on Martin Colloms testing in Stereophile.
In a small area it was enough output. The F6 ran hot with Concertos. Hotter than with my 8 ohm, 90 db efficient DIY speakers. It sounded fine, but I believe more power would have been better, drawing out more from the SB monitors. Eventually will try my F5T v2 (50w), but it's out on loan. I think the same would happen with the Maggies. More power might draw out more detail and control them better.
Just my observations. Take them for what they're worth to you.
Vince
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I have been using a pair of 100W Aleph X monos to drive a pair of 3.6's. They do a very good job. I am in the process of building a pair of large BA-3 monos to replace them. I am looking forward to an improvement in my system.
I think the Pass DIY universe has a solution for almost any situation. It's just that sometimes one needs to scale things up or down a bit. With Maggie's it's generally up.
Graeme
I think the Pass DIY universe has a solution for almost any situation. It's just that sometimes one needs to scale things up or down a bit. With Maggie's it's generally up.
Graeme
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The Maggie's are a different type of speaker. Hard to pinpoint the amp because they will eat up as much power as you give them. I had a pair of MMGs and I tried them on 6 watt tube mono blocks and they sounded good. Not loud but a good level, I have a small room. I also ran them on SS 1000 watt mono blocks. They got louder but not as loud as you would think on 1000 watts. But there is something addictive on their sound, its just clean and crisp. My advice is to try them on as many different amps you can get or build.
Before seeking out the "perfect" amplifier for these; search "Gunned" Magnepans. The MMG in particular seems to occupy the sweet spot of resolution for planar designs.
Having already trod this road, I would not recommend it for those who prefer amplifiers to be as simple as possible, but no simpler.
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Having already trod this road, I would not recommend it for those who prefer amplifiers to be as simple as possible, but no simpler.
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So we'll make what's needed and make it a little bit more complicated? I think you're missing the point of the saying.
Just say- a low powered class A amp isn't enough, or even better, tell us what works since you've been down that road.
"Gunned" looks like a speaker mod. What's it do for the amp that's connected?
Just say- a low powered class A amp isn't enough, or even better, tell us what works since you've been down that road.
"Gunned" looks like a speaker mod. What's it do for the amp that's connected?
I admire Papa's designs, particularly those with fewer parts - where possible. These sort of amps sound best to me.
I do not think amps such as those mate well with insensitive loudspeakers, such as Magnepans.
The best I've heard driving Pans are like the AVA designs: huge power supplies, multiple output devices and every spare part available to populate the feedback loop.
I had the big Unison DM monoblocks driving mine, until changing course.
While it may be a matter of taste, I feel that fewer parts in the playback loop sounds best.
As simple as possible, but no simpler.
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A F5T v3 100w monos, despite being simple stages, have large power supplies and multiple output FET. They can provide large amounts of current. More than 38A peak. Should be enough, right?
You're looking at $1500 to $2000 in parts, depending on what you buy, including cases from the store. That's my estimate.
Get crackin', or define what it is that these speakers need. My guess it has more to do with amp> speaker cables> speaker being driven, not just amp/speaker combo.
When running my Concertos/F6 combo, Monster Cable bi-wire 12 ga. sounded horrible. My on-sale Radio Shack 16 ga. shielded speaker wire for $29 got rid of all the hardness all the way up the upper highs. Became listenable. Why is that? If I knew, I'd be rich, but I bet someone here knows why.
Where's the hang up? Really being able to deliver into 4 ohms or less?
Watts db
1 86
2 89
4 92
8 95
16 98
32 101
64 104
128 107
You're looking at $1500 to $2000 in parts, depending on what you buy, including cases from the store. That's my estimate.
Get crackin', or define what it is that these speakers need. My guess it has more to do with amp> speaker cables> speaker being driven, not just amp/speaker combo.
When running my Concertos/F6 combo, Monster Cable bi-wire 12 ga. sounded horrible. My on-sale Radio Shack 16 ga. shielded speaker wire for $29 got rid of all the hardness all the way up the upper highs. Became listenable. Why is that? If I knew, I'd be rich, but I bet someone here knows why.
Where's the hang up? Really being able to deliver into 4 ohms or less?
Watts db
1 86
2 89
4 92
8 95
16 98
32 101
64 104
128 107
I don't know why the hangup but I know pairing amp with Maggies is an issue more than most speakers. Wish I knew more about why the Maggies are a difficult load but it's more than their nominal impedance. One issue is, as I said earlier, the need to be able to double power when halving the load (double power output from 8ohm to 4ohm, and again from 4ohm to 2ohm). Not because the amp is likely to see 2 ohm loads much but because it has to do with how the current handling is done in the amp design. I'm over my head here, but it's more than straight power or even current directly. And that's why I posted in the first place. Looking for people with experience with what works, ideally in the Pass world but not necessarily. I'm intrigued by Nelson's designs but I also know there's a wealth of info and help available here.
I did look at the F5 Turbo v3 as it seems promising. I'd be very surprised if it were $1500 or more to build (and beyond my budget). It doesn't sound too complex if I used the PCBs, which I would in this case. Simple enough linear power supply instead of tube-regulated makes that part relatively easy. I have a few 60,000uF caps at 50 or 60v. Antek has nice yet affordable power transformers, or if I could use a single ps transformer into otherwise mono block amps, I could save even more (I have something suitable on-hand). Did I say I'm on a tight budget? I've succeeded with tubes - listening to a SE tube amp now that is GORGEOUS sounding and cost me <$200 to build. So I think I can succeed with a Pass design inexpensively.
I also looked at the Aleph J since there is a PCB available AND I've read a few reports that it's a good amp with Maggies.
I did look at the F5 Turbo v3 as it seems promising. I'd be very surprised if it were $1500 or more to build (and beyond my budget). It doesn't sound too complex if I used the PCBs, which I would in this case. Simple enough linear power supply instead of tube-regulated makes that part relatively easy. I have a few 60,000uF caps at 50 or 60v. Antek has nice yet affordable power transformers, or if I could use a single ps transformer into otherwise mono block amps, I could save even more (I have something suitable on-hand). Did I say I'm on a tight budget? I've succeeded with tubes - listening to a SE tube amp now that is GORGEOUS sounding and cost me <$200 to build. So I think I can succeed with a Pass design inexpensively.
I also looked at the Aleph J since there is a PCB available AND I've read a few reports that it's a good amp with Maggies.
How much current did these amps have, on tap? I suspect that what makes the Magnepan design "come alive" is a robust power supply that can support the large panel, quickly.
Magneplanar addressed this, some years ago.
It's not definitive (buy this - don't buy that) but it addresses the hidden cost of getting the most from Magneplanar products.
FYI - I tried first generation Class D amps and found them less musical than simple Ultralinear designs of lesser output.
The larger Threshold amps would work, but will likely have age related problems that need repair. I'm not convinced it's worth all the trouble - when Quad ESLs, or more efficient designs are commonly available.
Again, it may come down to taste, but I dislike loudspeakers that are finicky, demanding or high maintenance.
"The most common question is about the amount of recommended power for Magneplanars, but, first, it is important to understand the role of current and the power supply. High current and the capability of the power supply is a good indicator of the QUALITY of the amplifier. The amount of power you will need is a matter of QUANTITY. High current and total power are two separate issues.*
The power supply is "what separates the men from the boys." A receiver is very efficient and cost-effective way to get is all in one package, but there are "issues". Unfortunately, consumers want all the "bells and whistles" without understanding the importance of power supply. Many manufacturers offer the "bells and whistles", but, compromise the power supply to be price competitive. There are a few manufacturers that are the exception."
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