I am trying to decide between the LM3886 Done Right and the Modulus-86. I am not a novice with electronics, but a bit with audio. But board assembly is not daunting to me I work as a Biomedical Engineer.
Looking at the specs, they both seem close in THD, both appear to have inaudible distortion, but the Done Right appears to roll off a bit in the high end compared to the Modulus-86
1. Is there a large subjective sound differance in the two?
I primarily listen to Classical and Jazz, with some classic rock and Irish folk music occasionally in the mix. I am undecided as to a preamp. Speakers will be some Voigt pipes with a single driver, i.e. Fostex FE206En, Audio Nirvana Classic 8 FERRITE, or Tang Band W8-1772 (undecided at this point).
2. Can either be powered by an external SMPS like: GST220A48-R7B MEAN WELL | Mouser ? In case the link is blocked is blocked, it is a Meanwell GST220A48-R7B 48V 220W external power supply.
3. Would this have sufficent amperage and voltage to drive the amp to about 25 watts into a 6 to 8 Ohm load? Would I need one for each channel, or would a singular supply suffice?
4. How closely does each channel's components, i.e. caps, resistors, chipamp have to be matched?
Thanks all.
Looking at the specs, they both seem close in THD, both appear to have inaudible distortion, but the Done Right appears to roll off a bit in the high end compared to the Modulus-86
1. Is there a large subjective sound differance in the two?
I primarily listen to Classical and Jazz, with some classic rock and Irish folk music occasionally in the mix. I am undecided as to a preamp. Speakers will be some Voigt pipes with a single driver, i.e. Fostex FE206En, Audio Nirvana Classic 8 FERRITE, or Tang Band W8-1772 (undecided at this point).
2. Can either be powered by an external SMPS like: GST220A48-R7B MEAN WELL | Mouser ? In case the link is blocked is blocked, it is a Meanwell GST220A48-R7B 48V 220W external power supply.
3. Would this have sufficent amperage and voltage to drive the amp to about 25 watts into a 6 to 8 Ohm load? Would I need one for each channel, or would a singular supply suffice?
4. How closely does each channel's components, i.e. caps, resistors, chipamp have to be matched?
Thanks all.
Both the amps you mention (and 99% of similar ones) need a split supply which means two voltage rails, a positive and a negative. Traditionally this is provided from a dual secondary transformer and bridge and caps.
SMPS is a possible option but the one in your link is a single output... I think there are some dual rail types on the market. Some also run two single types in series to generate a dual rail but that depends critically on the individual SMPS concerned and is not a route I recommend.
Component matching is a non issue given that all such projects use close tolerance parts. Don't even give that one a second thought.
SMPS is a possible option but the one in your link is a single output... I think there are some dual rail types on the market. Some also run two single types in series to generate a dual rail but that depends critically on the individual SMPS concerned and is not a route I recommend.
Component matching is a non issue given that all such projects use close tolerance parts. Don't even give that one a second thought.
I have heard a number of Tom’s amps and they were very good. The other i know not.
Neither amp is really suitable for the FE206, it wants a high output impedance amplifier. If you want inexpensive and SS then a set of bridged/balanced ACA. Way more power than needed, but the right Rout and is a very good (but different) sounding amp. The FE206 wants to be in a horn, a voigt horn almost universally needs to be an ML-Voigt. It might work, i’d have to have Scoot look. My usual recommendations are Dallas II, Kirishima, and Vulcan. A member recently posted his build process on his Kirishima.
I haven’t heard the 8” classic, the 10” was REALLY bad. W8-1772 is quite popular but i feel more coloured than i like and pricier than drivers i prefer. It would be happy with a good LM3886 chip amp.
Scott & i are currently working on an ML-TL for the W8-1772, it is often quit epossible to convert to an ML-Voigt. At first blush it looks like it would be 80” plus tall if not folded.
For the amps you are looking for i would look elsewhere speaker wise. Amps & speakers have to be considered a system. What are your speaker needs?
dave
Dave,
I heard some Voigt tube/transmission line speakers with the Tangband and they were wonderful.
Many years ago I had a set of PSB 50R speakers that were 2 way ported base reflex and a Carver receiver. They were a little weak on the bass, but the mids and high end were unreal for clarity. The system got lost in a move, and I fell out of HiFi interest due to time and $$.
I want something that is good with classical music and vocals. I had thought of using the amp camp amp, but classical tends to need a fair amount of dynamic headroom and I felt that might be disappointing. I also want a speaker with a small footprint, height isn't an issue.
Thanks
MikeW
I heard some Voigt tube/transmission line speakers with the Tangband and they were wonderful.
Many years ago I had a set of PSB 50R speakers that were 2 way ported base reflex and a Carver receiver. They were a little weak on the bass, but the mids and high end were unreal for clarity. The system got lost in a move, and I fell out of HiFi interest due to time and $$.
I want something that is good with classical music and vocals. I had thought of using the amp camp amp, but classical tends to need a fair amount of dynamic headroom and I felt that might be disappointing. I also want a speaker with a small footprint, height isn't an issue.
Thanks
MikeW
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Footprint of a Voigt can be narrow, but will be deep.
1st guess:
82” x 12.5” x 13” (h x w x d)
With driver height at 40” a retuning to shorten the box (an dthe driver) might be required.
dave
1st guess:
82” x 12.5” x 13” (h x w x d)
With driver height at 40” a retuning to shorten the box (an dthe driver) might be required.
dave
The The Spawn Family of Double Horns and Woden Design | Vulcan appear a bit large for my room. However that Dallas II looks interesting.
The THD+N of the LM3886DR approaches/exceeds audible towards the high end of the audible spectrum. It also rises with frequency. I believe (based on my own subjective experience) that this is what gives the LM3886 its "chipamp sound". Many like that, others find it a bit too harsh.
I find the Modulus-86 to sound much cleaner. All the harshness of the LM3886 is gone. Also, once you factor in the cost of the heat sinks, chassis, power supply, etc. the price difference between the LM3886DR and Modulus-86 is maybe 10% of your build budget. In my opinion, it's well worth it to spend 10% more and get 10-100x lower distortion.
I have yet to find a speaker that the Modulus-86 did not drive well. I've used a variety of speakers ranging from full-range to multi-way with/without active crossovers. Some of the speakers were of Dave's (Planet10) design.
That SMPS is not a good choice as it only provides a single +48 V supply. You need a split supply. I recommend ±28-±30V. The Connex SMPS300REh (±30 V version) would be ideal.
They don't. Just build it according to the instructions and you'll be fine.
Tom
As long as you get a high Rout amplifier to match the speaker.
A band aid would be added series resistance. Better IMO, to get a proper amp.
FE206 with 15 watts plays really quite loud… say 115 dB peaks (1m. 1 speaker), likely more, the horn helps bring the bass dynamics needed and helps with the issue of classical being so dense.
dave
A band aid would be added series resistance. Better IMO, to get a proper amp.
FE206 with 15 watts plays really quite loud… say 115 dB peaks (1m. 1 speaker), likely more, the horn helps bring the bass dynamics needed and helps with the issue of classical being so dense.
dave
Tom
Do you have a spectrum. The THD measure si have seen are meaningless (we have discussed that and disagree). Rout is also far to low to match the FE206. The big amp of yours was fantastic but Rout could have been a bit higher for the big A12pw MTMs in that demo.
Would work well with the TB.
dave
Do you have a spectrum. The THD measure si have seen are meaningless (we have discussed that and disagree). Rout is also far to low to match the FE206. The big amp of yours was fantastic but Rout could have been a bit higher for the big A12pw MTMs in that demo.
Would work well with the TB.
dave
Tom,
Thanks for the quick answers. Price wasn't the concern as much as building a good sounding and a quality amp. I checked out that Connex SMPS and it seems to be well built.
Are your preamps ideally setup for an external enclosure or to be integrated in the amplifier chassis? If I wanted to add a tone control do you have a solution? Or would a Schiit Loki be suitable?
BTW, very good, interesting and engaging interview.
Thanks
MikeW
Thanks for the quick answers. Price wasn't the concern as much as building a good sounding and a quality amp. I checked out that Connex SMPS and it seems to be well built.
Are your preamps ideally setup for an external enclosure or to be integrated in the amplifier chassis? If I wanted to add a tone control do you have a solution? Or would a Schiit Loki be suitable?
BTW, very good, interesting and engaging interview.
Thanks
MikeW
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When the THD is 118 dB down, does the spectrum matter? Inaudible is inaudible. Either way, see attached.
I'm not aware of any science that backs that up, so we will have to disagree on that. We were quite a few in the room who disagreed with you during that demo, by the way.
If the best sound quality is your top concern, build the Modulus-86 (or -186 if you need lower noise; -286, -686 for higher power).
I especially appreciate the bottom plate that Connex has added. The SMPS300REh is a further development of the SMPS300RE. The 300RE had one weak spot: The output diodes tended to overheat. That's fixed in the SMPS300REh. They also upped the ante and package the supplies individually, so they all arrive intact if you order more than one.
Either way is good, though, personally I would probably go for a separate chassis. I don't offer a tone control.
Tom
Attachments
FWIW, several years ago I had the opportunity to audition the LM3886DR and Tom’s personal Mod86 (4 channel for his LX Minis, IIRC) in my home system prior to one of the fests at Dave’s, and would heartily concur that the complexity and extra expense of the Modulus circuitry is worth every penny.
I ended up acquiring one of Tom’s limited release Mod286 kits, and after a several decades of building all sorts of scrap box DIY projects to fully parts supplied kits would definitely look at the pre-assembled Mod186 module.* Being retired with sufficient financial comfort, I can afford to be at least that lazy. Of course, fabricating a tidy chassis is often the most time consuming and costliest part of such a build.
Re the 686, for me it was a major disappointment to have to disconnect it from the Alpair MTMs. Indeed, if it wasn’t for their footprint, I could be quite happy with that combination in my main system. As can be imagined, there’s no dearth of permutations of speakers and amps at such events, and attempts to arrive at general consensus as to “best of show” are generally fruitless, but we can certainly reach our own conclusions.
*If I’m not careful, I may yet talk myself into completing the outboard powering of my 7.1 rig. While the room configuration doesn’t permit major upgrading of speakers from the current Alpair/Pluvia, amps would be a different story; and at my normal playing levels the height /rear surrounds should be more than happy with the power from a single 3886 per channel.
I ended up acquiring one of Tom’s limited release Mod286 kits, and after a several decades of building all sorts of scrap box DIY projects to fully parts supplied kits would definitely look at the pre-assembled Mod186 module.* Being retired with sufficient financial comfort, I can afford to be at least that lazy. Of course, fabricating a tidy chassis is often the most time consuming and costliest part of such a build.
Re the 686, for me it was a major disappointment to have to disconnect it from the Alpair MTMs. Indeed, if it wasn’t for their footprint, I could be quite happy with that combination in my main system. As can be imagined, there’s no dearth of permutations of speakers and amps at such events, and attempts to arrive at general consensus as to “best of show” are generally fruitless, but we can certainly reach our own conclusions.
*If I’m not careful, I may yet talk myself into completing the outboard powering of my 7.1 rig. While the room configuration doesn’t permit major upgrading of speakers from the current Alpair/Pluvia, amps would be a different story; and at my normal playing levels the height /rear surrounds should be more than happy with the power from a single 3886 per channel.
Chrisb,
For me speakers are the easy part. I have a fully oufitted wood shop and want to experiement with box design. What I am trying to do is build a reference amp, one that is not harsh yet accurate. From reading the specs on Tom's design, and the specs are impressive, I am going the Modulus-86 route.
I just pulled the trigger on the boards.
For me speakers are the easy part. I have a fully oufitted wood shop and want to experiement with box design. What I am trying to do is build a reference amp, one that is not harsh yet accurate. From reading the specs on Tom's design, and the specs are impressive, I am going the Modulus-86 route.
I just pulled the trigger on the boards.
So I see. Thank you very much. I really appreciate your support. I just packed up your boards. They'll be underway tomorrow.
Tom
Tom
You know way more about amplifiers than i. I know more about loudspeakers.
The FE206 was designed to be horn loaded and driven bt a high Rout amplifier (pharaphrased from the designer). It has a very low Q and if you use an amp like yours the bass will be very thin and they will sound very unbalanced.
dave
hey, if you are interested in 4 channel mod86 kit, I have all the parts sitting in my closet. Willing to sell it all. Send me a message. Just don't have time unfortunately to focus more attention on audio.
I had the pleasure to meet Tom and listen to his amp and the LXMinis at my house. It was fantastic. Even my daughters could tell the sound was very real, vivid. Don't hesitate to buy from Tom, straight up guy! And awesome support.
I had the pleasure to meet Tom and listen to his amp and the LXMinis at my house. It was fantastic. Even my daughters could tell the sound was very real, vivid. Don't hesitate to buy from Tom, straight up guy! And awesome support.
Perfect candidate for preamplifier bass tone control!
Loudspeaker with thin bass is loudspeaker enclosure design failure - don't blame the amplifier for that. There are plenty good designs of horns for drivers with low Q - but they must be big enough. If the horn designs are bad (or not big enough), they will have thin bass. An amplifier has nothing to do with that.
If you have incapable driver to start with, don't hunt a suitable amplifer. On the contrary: use good and capable driver mounted in the right enclosure - it will work fine with any decent amplifier with low distortion and low output impedance.
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Doesn’t work near as well. This speaker was designed for small SE tube amps so popular in Japan.
The popular one si know of also pefer an SE amp.
Neither of you guys should get FExx6, you won’t be able to appreciate what they do.
dave
I have heard Fostex FE206 in back loaded horn, driven by EL34 SE amplifier. Sorry, but I can not appreciate polishing the turd.