Music First Audio Passive Magnetic Preamplifiers?

I want to know if anybody tried and compared this rare preamplifiers.
I´m really interest on this brand but I couldn't find anything here in Audiogon.
I will apreciate your opinions.
Hi Elduende14, I think you are asking about the Music First passive preamp which is transformer based, not magnetic. This type of passive is called a TVC for transformer volume control, instead of using resisters.

Yes, I have heard it, however it is insanely priced and does not sonicly out perform the pieces of John Chapman's Bent Audio. His current passive uses autotransformers, offers many more features, is beautifully built, sounds great and is very fairly priced. You also get a 30 day audition period to make your decision. John's also a great guy to deal with.

Take a look at my review here on the GON regarding the details of the Bent Audio Tap passive TVC preamp, which apply to his current model.
Unfortunately, John no longer makes the Tap X autoformer preamps, but you can get his modified Slagleformer for DIY.
Dracule1, are you sure John has stopped building the Tap X preamp? Only a cuople of months ago a friend called him to discuss the Tap X and he was still building them then. His website still offers it as a current model. Please share more about this matter, thanks.
I recall John posting something on his forum about taking a break from manufacturing the Tap-X autoformer units. However, he did offer to build a balanced one for me, so maybe he's back to doing them in small runs or one-offs.

To me one of the best passive preamps out there is the Lightspeed Attenuator. There is one here for sale that came up today.

I never heard the Music First units, but I had a passive preamp using S&B transformers that I liked. These are the transformers used in the Music First line. However, as mentioned the Music First units are over priced.
Teajay, my understanding is that since he is OEM for Bent modidfied Slagleformers, he doesn't want to "compete" with manufacturers he provides parts for. His Tap X is a relative bargain compared to those building preamps using his parts. I think he has his hands full doing OEM work. But I guess you really need to ask John. He may have changed his mind.
Music First is definately the MOST overpriced passive preamp out there. And it doesn't have functionality of the Bent Tap X.
More overpriced than the Audio Consulting Silver Rocks?

No, the Silver Rock is more overpriced, but I think it sounds much better than the MF. Also, I have compared the Silver Rock to the Lightspeed Attenuator I mentioned and for roughly a tenth of the price the Lightspeed is a steal.
I'm using a MF copper version in my system, it is much better of my old Audible Illusions M3 in every aspect: much more details, excellent image, very well balanced sound.
I use it with a VK-55 power amp and Hyperion HPS 968 speakers.
I bought it used (excellent conditions) at 1600 Eur; it is very well built and UK people that make it are very kind and supportive.
They're both way over priced. Can't justify buying something that's been marked up like that.
Nigi25, I bought the Hyperion 938s when theyfirst came out in '94. Hope your enjoying the 968s with tubes. Hyps are some of the best speakers under $10k.
Hello Dracule1, I love the HPS968 with VK-55, I'm waiting for a Bladelius Gondul Mle CD player, it is one of the best CD players available and it includes a preamp board, so I'll go directly to the power amp from the CD player.
I second Clio9's recommendation of the Lightspeed Attenuator which is a real steal new ($450), not sure what the one up for sale cost. I have used the following passives Placette RVC (and "Active"), BENT TAP-X autoformers, Goldpoint, Music Reference PiaB, and K&K TVC with S&B mkIII transformers. The Lightspeed is as good as any passive I have used in my system and it just possible I might keep this as one of my preamps till it stops working 50 years from now. Single-ended, and one input only (part of the reason it sounds so good?). Saying that, all of these passives will sound very good to excellent with sensitive amps, short ICs, and 100kohm amp input impedance.
Pubul57, could you compare the TAP-X to your Lightspeed preamp? What are the strengths and weaknesses of the two? Thanks.

I got a hold of a Bent TAP-X and planning to get an LDR preamp of my own later.
I think they are very similar in mids and highs, where I find the LS amazing is in the quality of bass and dynamics - not that the BENT is a slouch, but I wasn't expecting it from a resistor based passive which needs more careful system matching than the TVC. If the quality of the attenuator is of extreme importance, not sure how you can get better than no contact (light) control of resistive values and related attenuation of a signal. Clio9 is far more articulate than I and has done more A/B listening to passive, my listening has been sequential so my comments are more impressions based on memory. Clio9 has done much more heads up comparisons. I can only say I love the Lightspeed in my system and I never quite felt that way with previous passives - though I certainly though they were very, very good and exceptional value compared with actives of anywhere similar quality. I would like to hear a LS attenuation control within my active tube preamps (Joule and Atma-sphere) - it would interesting hear this purist of attenuators to control volume within an active environment.
What the Lightspeed showed me that no other resistor designed passive showed me was that a transformer designed passive (Pubul57 bought the K&K from me) can actually compress the sound a bit, especially in the highs. To me this is not problematic and actually contributes to a slightly warmer and pleasing sound. However, it means that a TVC is not necessarily the last word in transparency and neutrality.

Now autoformers are not transformers since they have just a single winding. However, there is some debate among people I trust who make transformers for a living as to whether the Slagle designs are actually autoformers. I won't get into specifics on that discussion here. However, in my comparison of the Lightspeed and Slagle AVC I own, the AVC acted and sounded like my old K&K S&B, just more transparent and neutral, but not as transparent and neutral as the Lightspeed.

The Lightspeed is the king of the hill of passives IMO. If you have a system that matches up well with it you will be extremely surprised at how good it sounds.
I was at the Lone Star Audio Fest and heard a LDR preamp. I was surprised how smooth, transparent, and natural it sounded compared to a tubed preamp. There is a Serbian company that makes a fully functional remote controlled LDR preamp called Myth. It costs around $1700, and I almost bought it. However, factor in $300 for shipping and cost of shipping both ways if something goes wrong is just too much hassle.
Yes the "Myth" this is a blatant rip-off of my Lightspeed Attenuator design, how can one charge $1700 + $300 shipping for just a bit more glitz and a remote is beyond me. I have been asked many times to do a remote model and I figured it to still be under $1K, some people reel back at my $450 shipped price tag, so it will probably never eventuate.

Cheers George
The Myth product has been around and used to use to be referred to as the Myth Lightspeed preamplifier in it's marketing. George Stantschleff pressured them to stop using the reference to Lightspeed and I can validate, having looked into the product myself, that the Myth is as George says, a remote controlled multi-input Lightspeed.

Anyone really interested in the history and variants on the Lightspeed (including a Nelson Pass design) should muddle through the lengthy thread over at You might even be inspired to build one yourself.
George, you have been working on this for a few decades, any ideas cooking on how to make the Lightspeed better yet, or is there nowhere to go at this point? Isn't your idea patentable?
Reading through the thread I believe he tried to patent or had a patent. However, it's perfectly clear he was the first to come up with this design since copied by others including Melos and Datzeel.
DIY is no threat, since that community is going to reverse engineer this stuff anyway, for electonic dopes like me, I am more than happy to pay George, have him make a profit on what is simply an amazing sounding piece of gear, and a SOTA, single input preamplifier that can compete with any preamplifier in the world with careful system matching between source, pre, cables, and amp. Not for everyone, but in the right system about as good as it gets IMHO.
Sorry George, didn't realize it was a multi-input remote controlled copy of your preamp. I think many would consider buying a multi-input remote controlled version of your Lightspeed preamp. I understand your preamp was "advertized" to the DIY crowd who tend to spend less on audio gear than the typical audiophile. John at Bent Audio had a pretty successful run of his remote controlled multi-input/output TVC/AVC preamp, and he was charging $1600 to $3000.
I first did the Lightspeed Attenuator back in 1975 but the LDR's were horrendous to keep calibrated I thought about patenting it but with zero reliability what was the use, it still sounded to everyone as the most transparent/dynamic pre they ever heard. I shelved the idea till I hoped LDR's became more reliable.
Melos then tried it in the 90's their kilo's $$$buck SHA-Gold reference all these failed also probably what sent them broke. Also Haffler had a stab at it around the same time. And now Dartzeel don't get me started on that one.
It wasn't till the early 2000's that I finally found reliable LDR's that would stay matched. This is the story why now I cannot patent the idea I should have done it back in 1975. But I can stop others from trying to patent it for them selves.
As for making it sound better, simply, no, what I make is a good as it gets, extra inputs sound worse because of the switching, remotes do nothing for the sound, my philosophy with it is KISS and keep it affordable.I have even run it off pure battery power, we say there is a very slight difference but no one can tell what the difference is, even golden ears Sam Tellig
I first did the Lightspeed Attenuator back in 1975 but the LDR's were horrendous to keep calibrated I thought about patenting it but with zero reliability what was the use, it still sounded to everyone as the most transparent/dynamic pre they ever heard. I shelved the idea till I hoped LDR's became more reliable.
Melos then tried it in the 90's their kilo's $$$buck SHA-Gold reference all these failed also probably what sent them broke. Also Haffler had a stab at it around the same time. And now Dartzeel don't get me started on that one.
It wasn't till the early 2000's that I finally found reliable LDR's that would stay matched. This is the story why now I cannot patent the idea I should have done it back in 1975. But I can stop others from trying to patent it for them selves.
As for making it sound better, simply, no, what I make is a good as it gets, extra inputs sound worse because of the switching contacts, remotes do nothing for the sound, my philosophy with it is KISS and keep it affordable.I have even run it off pure battery power, we say there is a very slight difference but no one can tell what the difference is, even golden ears Sam Tellig
What about the Lighter Note preamp? Do you consider it to be a blatant rip off also? Seems like it has a different power supply than the Light Speed.
The Lighter Note is a circuit parts only kit, you still have do all the chassis, rca and ancillaries etc yourself. Uriah did ask me if he could sell matched "pairs" of ldr's on DIYAudio for members and I said yes to that, I do go one further and do matched "quads sets" in the production Lightspeed Attenuator, it gives a better logarithmic feel to the volume control but is exponentially harder and costlier to match up. As for the powersupply it makes no difference, as a battery, as you know is the best form of dc power one can do for the led's and it is no better that the double regulated power supply I give the production Lightspeed Attenuator.

Cheers George
George, is there any improvement to be had with the chassis and shielding and/or vibration control in a way that might make any audible difference (not just "pride of ownership" bling?
Hi Paul, your Lightspeed Attenuator chassis is fully shielded alloy, it gets it's RF sink earth via the interconnects. Vibration doesn't come into it as there is nothing to get vibrated as it's passive, even the active led's are immune as they are gas element, no filaments. The feet I attach are soft silicon/sorbethane compound anyway just in case. Glad to see you love as much as others do. It would also be unsuccessful to be transplanted within pre's or poweramp environments as the temperature is too erratic within these chassis for the Lightspeed components to behave stably, I even physically couple all the ldr's together after precise matching and then pot them in hard wax to keep everything stable in the your production one.
Cheers George
A simple one at
It also listed in the manufacturers listings on Audiogon

Cheers George
Also if you PM me your email address I'll send you a PDF broucher.
Cheers George
I've just come across this thread and see that the Myth preamp was mentioned by Dracule1 and others. I have this preamp and I'm extremely happy with it. In my system it provides great detail and transparency, which I got from a transformer passive pre that I had before, but the Myth also has a sense of weight and realism that the TVC lacked. I find the bass well extended and articulate, the mid very clear, and the treble possibly not as sparkling as some equipment but still characterful and balanced.
It has the big advantage of five inputs, because I don't want to have to get up, switch everything off, change cables, and switch it all back on again every time I change from vinyl to CD.
But the biggest advantage of the Myth over other LDR preamps is that it has a buffer that gives it an output impedance of less than 3 ohms, which is necessary to match the input impedance of my power amps.
I haven't heard a Music First or the Bent TAP-X, but some of those who have made comparisons reckon that the Myth is better than the former, and in some respects beats the latter. So with its facilities and useability in my system it's definitely worth the price.
Since the use of LDRs for attenuation is in the public domain I don't understand the hostility towards the Myth that's expressed in some quarters, and I notice that the term "Lightspeed" is used by a cable manufacturer and a mains conditioner, so that doesn't appear to be anybody's copyright.

I've heard the copper and silver versions of the MFA. They sound great but, yes, very overpriced. You have so many more options if passive is what you want. I had the Bent Autoformer preamp and absolutely loved it. Much cheaper than MFA. Others to consider: Placette and Django. Also I understand the Dodd is very special (which is battery powered, I think).
I own the MFA copper classic and the MFA Reference. They are worth every penny IF you value sound. I have directly compared it to the latest Tube Research Labs $35k preamplifier and the classic walked away from that unit. I have also c impeded it to the $20k (latest version) Concert fidelity Pre ( which at this point is to my ears the finest active line stage I have heard) and while the Concert Fidelity was better than the Classic; the classic certainly was not embarrassed. The classic lost out also to the $24k audio research anniversary unit but again..., it was not an embarrassment. The latest Allnic with the upgraded transformers was no contest at all and that unit was $12k.

Value is in m opinion not just the sum of the parts, but also the intellectual property that went into a thing and also..., can I get that same sound and build quality somewhere else.

Now the Ref is just iin another league altogether and if you haven't heard it or been able to do real head to head comparisons in the same system at the same timel.., I would suggest you know not what you are talking about.

I have searched a long time for reference pieces and for me these two units are amongst the best I have heard.

I would rank as follows
Concert fidelity (latest) = MFA Reference 20k and 16k respectively
Audio Research Anniversary $24k
Karan reference mkII ~$21k
MFA Classic copper ~$2.9k
Oh yeah, my classic does NOT have the mk II transformers. I'm sending it back to MFA for the upgraded xformers and the remote option. Im also having a custom bypass switch installed so I can do comparisons more easily between different digital volume controls i.e. Pure music, Audiophileo....etc.
The MFA is said to sound very much like the BENT Audio passive when it used the S&B transformers, I thought the Slagle autoformer version - the BENT TAP-X - sounded even better if you can believe it, and better yet the Lightspeed Attenuator. Given the equipment you have been listening too, I know you could easily try the LSA - not full featured or anything, but for sound? I've not heard a better passive.
I built a passive for my bench testing of audio equipment Ive built (amplifiers and such) using shallco and roderstein mkII resistors. I had a buddy visit my uncle who was using my passive and he commented that it sounded exactly like the LSA. He owns the LSA but I have never heard the LSA with my own ears so i can't second his opinion. I can say that I would rather listen to my classic or Ref MFA units than the resistive passive I built :)

Honestly I'm not knocking the LSA but i probably will not go out of my way to audition it either. I love the fact that the MFA units will inherently convert a S.E. signal to a balanced signal as well.

Perhaps my uncles buddy will bring his LSA by one day in which case illl haul the classic over :)
Yes, I think that the type of quality one can approach with the classic at ~3k is astounding with the copy classic...I'm not a fan of silver wiring so much :) though I have heard some silver sound quite good.

I'm sure the Bent Audio gear is extremely good as well but I have not been privy to it. I also once had the Bat Rex, absolutely no contest for the classic.

Audiofun, what does your system consist of? Was the shootout performed in your system or someone else's? Was it blinded in any way?

I am curious to hear more about the "current generation" TRL reference pre-amp you heard since most of those units are overseas. A majority of the references stateside are 10-15 years old (and older....).

There have been recent shootouts between the recent generation TRL Dude (mid-level TRL unit) and the Concert Fidelity and AR anniversary addition by people I know in high resolution systems with state of the art conditioning, etc, and the results were the exact opposite of your findings.

After spending the past weekend at Axpona, it reconfirmed that audio is a wickedly subjective hobby and seems to be steered by system and brain chemistry more than anything else. I guess that is part of what makes it entertaining and fun....
Hi Agear, one of my best audiophile friends thought he was set if not for life, at least for a very long time with the TRL reference preamp, I believe it was the latest generation, until he auditioned the Concert Fidelity in his system, and sold off the TRL piece as fast as he could.

This only proves that their is no "BEST" of anything in our crazy/fun hobby. It comes down to personal taste and system synergy.
I agree that Music First is way overpriced...
By the way Music First just sells Billingtons made transformer, you can buy them directly for much less money :
Agear, none of the tests were blind. I do not understand the point of your statement that most "current gen" TRL gear is overseas, this "current gen" TRL gear is in Chicago:) As a former owner of both the GT 200 mono blocks and the GTP 2 preamp (TRL) I'm very familiar with this gear. 

The Pre was the (if I recall correctly) GT4 but I will check with my uncle tomorrow (and I assure you the Pre and the 300 watt TRL monoblocks are right here in the good old USA :) The comparison was performed at my Uncles place with me having taken my MFA units to his house as we often do shootouts at his place do to his dedicated listening room, plus the fact that I'm younger and it is much easier for me to haul gear :)

Hi Teajay, it's my uncle you are speaking of :) 

Oh, the preamp and amps mentioned (TRL) were made to order in the last year and a half I believe. Th GT4 unit is far above the TRL DUDE.

Everything eventually gets surpassed and while I thought my TRL gear was the best gear ever 10 years ago, I have owned and now own amps and preamps that flat out surpass that line of gear, however, YMMV :)
N37000, if those are still available, that is an AWESOME price and I would suggest people jump all over it :). I have sent a question to MFA concerning your' points, however, I think MFA is the finished product line entity if you will of S&B. I also am pretty sure they stopped selling their transformers to other parties.

I will update this thread with the answers I receive from MFA but thanks for the info :)
I believe S&B stopped selling the transformers for DIY and OEM purposes a while back, which prompted John Chapman of Bent Audio to switch to the Slagle autoformers for his magnetic passive preamps.
Clio09 i believe you are correct air oall points. Here is the response I received from Harry at MFA/S&B in response to N37000's post;

Thank you for your message.
Yes, the S&B TVCU is still available. This uses a more basic transformer than the TX102 used in the MFA Classic Preamplifier, but it's performance is still very good. We also offer this with the TX102 transformer upgrade at £1100.00 GBP.
We do not supply our TX102 transformers to any other other companies and we have not done so for at least five years. Therefore, either this person is mistaken or the transformers are not genuine.
I hope this helps.
Many thanks and very best regards
Agear it is pretty cool that we ran nearly the same comparisons with some fairly esoteric gear. What variant of the Concert Fidelity were you listening to and where did you perform the testing with the 3 units ARC Anniversary, Concert Fidelity and TRL? 

What we heard with these units vs the GTP4 did not leave much room for interpretation. It (GTP4) simply fell by the wayside, so i find it all the more iteresting that you say the mid level preamp was better than the CF and the ARC. 

Interestingly enough, if memory serves, i liked my former GTP2 (when paul used 3 paralleled 6sn7 tubes per channel) more than the GTP4 which I am pretty sure is using the 6AS7 tubes.

I found that Pre (GTP4) to be a bit soft and lacking in weight and force. Interestingly I noted a lack of transient or leading edge snap with the GTP4. I say interesting because it lends creedance to something written by Bruce Rozenblit of Transcendent Audio fame in which he described his NOT choosing that particular tube (6AS7) for his OTL amps for that very reason. He stated that with the 6AS7 he found it lacked the ability to produce the leading edge transient satisfactorily quote, "Tests were run with the 6AS7 and it was found to be unable to produce the sharp transient attack required for the best performance". 

Now having written this, I have not heard the ~5k Dude and i have no idea what tube compliment it uses. Perhaps it is better than the GTP4.., but for roughly $30k less it probably should not be :)

Best regards
I have the Bent Tap X, and it is one of the most transparent passive I have heard with flexibility no other passive can match. It was about $2000 USD for the 6 input version. It still doesn't beat going directly from my DAC to amp, but gets it pretty close. Too bad it is now out of production.