Spectral 260 amp preamp and cable compatibility

[Mobiusman]

My simple system upgrade that began as looking at Audiogon as a way to avoid studying for a board certification exam last December has hopefully come to an end because it is time to get back to life and quite simply I am running out of funds for this project. Having said that, I am thrilled with the end results and listening to more music than ever (literally).

As is all too often the case being an audiophile in upgrade mode, there are things one learns about their personal being that are probably more important than upgrade equipment, and this experience is no exception. So before I share the specifics of what I have found, here are my personal growth points from this project. 1) I am quite a knowledgable audiophile, but I know less about Spectral amp interactions than Keith Johnson, the man who gave birth to one of the most amazing amps currently in production; 2) While I love the sound of tubes, I do not want to deal with the problems and maintenance of output tubes at this point in my life; 3) I think that my favorite sound comes from a system driven by a tube preamp and solid state amp (only certain combinations); 4) audio is less important than listening to music; 5) life is beautiful if you find a partner who loves listening to music as much as you do and she/he has no input on your audio budget.

As those of you who have read some of my previous posts, especially "My Experiences Building a Total Shunyata Zitron System", I have recently been trying to create a system that has a "quality" that I hear all to rarely at a upper mid-fi price point, because post-divorce, post-Sandy house loss, post near death car accident, I just do not want to go back where I used to be with audio. Well I kind of achieved my goal, except at a $100k price point (retail, thankfully). What I learned in this quest is that I have been missing a huge piece of the puzzle, namely the role of the power side of the equation and with Spectral amps, they need networks to protect and enable on the signal on both the incoming and outgoing sides. I also learned there is something to building power and signal cable systems, rather than my former approach to tune by mixed product colorations.

My problem is that I think that by and large the cable/power world is heavily inhabited by charlatans. However, one needs to be sure not to throw out the baby with the bath water, in that there are some truly talented people out there who are honest, despite the absurd prices they charge for their products compared to what they cost to design and manufacture.

Two companies that I have come to understand much better than I did previously are Shunyata and MIT. My experiences with Shunyata came out of a demo at CES 2012 and how nice and available key people in the company have been. With Shunyata, I believe it is important to think of them pre and post Zitron because from what I can tell having no direct pre-Zitron experience is that their new products run rings around their pre-Zitron products.

Put simply their products are incredible and offer some of the best relative value in the high end cable and power distribution world. They worked incredibly well, especially their power cords and Triton, for me until my most recent component change, a Spectral 260 amp. I love Spectral products because they are so darn revealing and fast, but can also be a bit too analytical for me if the entire signal system is Spectral, so I have tried mixing them with tube products, both preamp and power amp. The system I have recently built shows that Keith Johnson knows what he is talking about when he writes in the Spectral 260 manual "that while it is "desirable" to use all Spectral gear in the signal path, it is "essential/mandatory" to use networked cables (MIT) to get the best that their amps have to offer.

When I dropped the Spectral into my total Zitron system that I had loved previously, nothing blew up as many on this site have suggested. In retrospect the Spectral merely shut down when it experienced weird electronic scenarios, like an impedance of .6 ohms at 20k in my speakers. However, what forced my learning first hand about MIT was that some of the absolutely astounding sound of Spectral products that I have known for years to be their signature never developed. In fact the sound got worse as the amp broke in and became accustomed to the cables and vice versa. It was harsh, completely unlike the Shunyata Zitron signature prior to the Spectral, which was super smooth, detailed and inviting.

My audio partner in crime and best friend Marty from this site brought some MIT upper middle of the range products to try while he awaits his Spectral 400 amps. I do not believe that either of us was ready for what we heard with their progressive insertion, especially directly out of the box and completely unbroken in. The sound went from what Marty called "completely unlistenable" (this is the point where anyone who knows Marty should stop and have a good laugh), to what quite honestly sounded substantially better than his $60k tubed SOTA amps .

So with a gentle 4 letter expletive, I knew one more step would be required to bring this project to its end (please). It was time to buy some MIT products for the signal side of my system. Unlike Shunyata Zitron products which offer huge value for the money and sound great, MIT products, at least with Spectral, sound better, but forget about the huge value for the money part. They are super expensive!!!!.

So the part you Spectral fans were hoping was at the beginning of this post----- Here's what I have found with the BAT VK-32 SE tubed preamp feeding the Spectral 260. It is a good thing that it does not sound any better because it would start stealing feelings from what I feel for my lovely lady friend, who happens to love the sound as well. I have no desire to try putting a Spectral preamp in front of this because I have heard that combination with better speakers than mine and vastly prefer my sound.

I did as Dr. Johnson suggested and went from balanced Shunyata Zitron Pythons to single ended MIT MA-X interconnects at a retail price of $10k/pair for a meter. Fortunately my system only required two pairs of those from DAC to preamp and preamp to amp. Sorry, I just cannot afford to buy another long pair to feed my twin JL F113 subs. Besides I have yet to hear a better cable for subs than Belden 8214, balanced in my case with Neutrik terminations, although their break-in is painful until they hit their stride around 2 weeks. The MA-X have been in my system for about 10 days running with signal 24/7 and just continue to get better every day after the initial dramatic roller coaster ride during the first 48 hours. At this point and since the 48 hour mark, with the Spectral 260 as team captain, it is an insult to even compare them to the Shunyata's, although I would not be surprised if this is not the case with non-Spectral products. They certainly cost more ($20,000 versus $4,000 compared to the Shunyata's thus far)

Until 60 hours ago. The MA-X IC's were running with the Shunyata Zitron Anaconda speaker wire (excellent as long as you do not have a Spectral amp). The sound was totally listenable for all but possibly Marty, but there was a problem with regard to what I suspect was impedance matching between the Spectral 260 and my Martin Logan .6 ohm impedance at 20k which I believe was the reason I could shut the amp down at only reasonably loud levels. 60 hours ago another MIT sibling arrived, the Oracle HD 60 speaker wire with a network at each end. Using the MIT sense of financial reality, these were a bargain at merely $7000 compared to the Shunyata Zitron Anaconda speaker wire at $4000, but the MIT's were 12' compared to just more than 6' with the Anaconda's, almost a wash if you are foolish enough to categorize them using a cost per foot basis. Within 12 hours, the Anaconda's were rapidly getting progressively lost in the MIT dust. The sound was clearly the best I have ever had, and vastly better than what I typically hear in 95% of the high end CES demos. Oh yeah, the system plays much, more than 6 db, louder since the introduction of the HD 60 speaker wire. I guess all of those 68 Zobel networks in the network box really do make the ML impedance load less ugly, making the Spectral's protection circuitry much happier and my neighbors much less happy.

36 hours ago, hopefully the last of the MIT sibs arrived, the Oracle MA digital cable (S/PDIF) to go between my transport and Meitner DAC. This cable is quite interesting, especially for all of you who think bits are just bits. This little cable cost $4000 compared to the Shunyata Zitron Python at $750, it replaced. Although far from broken in, already the same variable sound stage control with 5 settings that is also present on the MA-X interconnects, and could be present on my speaker wire for a mere $5000 more, or $6000 per channel) makes a slightly less than dramatic difference. While this cable does not see Spectral idiosyncrasies just like the MA-X between the Meitner and my preamp, the overall sound difference is already scary good.

So in summary: 1) Spectral and MIT need each other to even sound good; 2) Spectral and MIT sound incredible together, but then the amp was designed specifically to be at its best with the MIT networks in front of and back of it; 3) think carefully if you like to play loud and have a speaker with a weird impedance curve; 4) the Spectral works just fine with a stable tubed preamp of proper output impedance, and in my opinion sounds more life like than a comparable total solid state system; 5) while Spectral products are priced incredibly cheap for what they provide, MIT is not, but yet is essential to realize the potential of the Spectral products. So in my relatively simple system, the real cost of inserting the Spectral 260 was $41,000, not the $10,000 price for the amp; 6) I would do this again in a minute, but hope to be done for years to come, although I might look into the Spectral Reference 300 amp when it arrives later this year to get more output; 7) consider Shunyata Zitron products as a total system if you do not have a Spectral product in the signal path; 8) I am sticking with the Shunyata power products because I love them and because I will start to resent my system if the MIT power products sound better because I do not want to spend more money at this point; and most important, 9) I am incredibly lucky to be able to afford this amazing system AND to have an absolutely amazing woman in my life who appreciates sharing this experience since she did not have to pay for it.

So as is always the case with audio, what I have written is totally subjective. I live about 90 minutes from midtown NYC on the water, cook quite well, have a wonderful boat with a full JL sound system moored behind my house. If you want to hear this thing and you still have retained most of your humanity and not just into audio as a way to compete and dissipate your aggression, give a call and maybe we can arrange a get together.

 

[Frank750]

Russ, very thoughtful and entertaining write up!
Glad you are happy with the results.

 

[marty]

I think Russ' description of his recent observations and assessment is pretty much spot on. As a post, he deserves kudos for combining the elements of entertainment, objective and subjective information, and psychiatric insight. The latter is generally in short supply on this site, so when its offered for free, who can complain!

My own experience parallels Russ' in some meaningful ways. I too have been a tube guy for a few decades. I too have owned early generation Spectral gear and moved on. I too have always considered networked cables anathema, and their originators better marketeers than engineers. But fortunately, I like to think that I am open to new learnings, as long as the learnings are data driven. I am a career scientist, and will therefore always try to evaluate changes in my system one variable at a time. That is potentially not feasible when it comes to Spectral/MIT since, as everyone knows, these are designed as a "system" by Keith Johnson whereby his electronics are meant to be paired specifically with MIT cables for the reasons cited by Russ and well documented elsewhere.

I'll be brief as I don't have the time for a prolonged discourse now. But like Russ, I have become a firm believer in the benefits of Shunyata AC conditioning. I had been using MIT Z network conditioning, but the Shunyata gear/cables offers a clear improvement. (Triton/Talos/Zitron cables). Next up, I have to say that as far as signal and speaker cables, the combination of MIT cables with Spectral amps in uncontested. However, like Russ, I'm not willing to take the dive into an all Spectral system and prefer to use my magnificent VTL 7.5 II preamp. Yup, gotta have tube sound (call it coloration, I don't care) somewhere. That combo works for me. It should be mentioned that like the Spectral preamp, the VTL has a very low output impedance, and in theory, is as good a match electronically for the Spectral amp as the Spectral pre-amp. Tube preamps such as ARC and BAT are higher output impedance units, but Russ certainly has had success with a BAT, and I have always suspected that ARC/Spectral would be an equally excellent pairing. Fortunatly, the MIT interconnects have adjustable impedance switching and can theoretically accommodate virtually any preamp out there.

Russ and I discussed why some of us old lions have impressions of MIT and Spectral that are less favorable than they might be based on current listening. No need to go into those reasons, except to say these impressions were generally formed with older iterations of both lines in less than optimal circumstances. The only thing I might suggest is that there is no substitute for doing listening the right way- in YOUR system at your own pace. If you do, I think you'll see why the accolades are abundant. That Robert Harley likes this stuff doesn't interest me in the slightest. That Bruce Brisson happens to be an outstanding marketeer doesn't interest me either. That Rick Fryer and Keith Johnson are the pictures you see in the dictionary when you look up the word "weirdos" is also insignificant to me. But the fact that the latest Spectral and MIT gear makes fabulous music is indeed something that I have been surprised to learn recently, and because of it, moved me from a sideline observer to an owner of that gear.

 

[ack]

Great write-ups! Figuring out Spectral is very similar to smoking: you are working with one of the best doctors in the business and he tells you exactly what to do. Yet you have your own opinions; until one day... Your experiences and approach is pretty much "by the book". Just keep in mind a couple of things, repeated on the net over and over: the amps feature no filtering, input or output; and think of what that means wrt oscillation and eventual distortion, and eventually (w/o MIT) destruction.

 

[mep]

From what little I know about Spectral gear, I believe they use extremely high-bandwidth circuits in order to achieve speed in their circuits. This requires going into the megahertz bandwidth for Spectral in order to get the speed they want. However, their amps and preamps don't want to see a megahertz bandwidth signal being fed to them which is why MIT designed cables especially for them to filter out those signals in case they are present so their gear doesn't go into oscillation and end up destroying themselves.

 

[KeithR]

Why not buy DMA400s at 28k/pair and cheaper cables? Wouldnt monoblock advantages subsume cabling ones?

 

[Mobiusman]

Keith,

I do not think that you can compensate for a design parameter (MIT networks) by moving up the product line. In fact I suspect that a 400 is even more network sensitive than the 260. Monoblocks typically provide better power supplies for each channel and better isolation. Since they are typically more expensive than stereo models, they typically have better circuitry, although similar. I think the key point I was trying to make with the Spectral is that the MIT networks are part, an essential part of the overall Spectral design. Fortunately I was able to find great deals on the MIT and spent $14,500 instead of $31,000, bringing the total to $24,500, instead of at least a total of $38,000 for 400's and lesser cables. Plus I am quite sure that the sound would be inferior.

 

[mmatuva]

Keith,

I do not think that you can compensate for a design parameter (MIT networks) by moving up the product line. In fact I suspect that a 400 is even more network sensitive than the 260. Monoblocks typically provide better power supplies for each channel and better isolation. Since they are typically more expensive than stereo models, they typically have better circuitry, although similar. I think the key point I was trying to make with the Spectral is that the MIT networks are part, an essential part of the overall Spectral design. Fortunately I was able to find great deals on the MIT and spent $14,500 instead of $31,000, bringing the total to $24,500, instead of at least a total of $38,000 for 400's and lesser cables. Plus I am quite sure that the sound would be inferior.

Russ - congrats on the search and a very successful outcome. I'm a recent Spectral convert too from end-to-end (I bought the 360 monos because I liked the monos in my room architecture and to drive my speakers, but the 260 was equally spectacular when I heard it). I have not had a chance to hear the 400s but the other factor in play here on the pricing (as I understand it), is that the 400s require dealer setup and installation at the buyer's expense. That's all fine and manageable if you are in Boston, SF, LA, Delaware, or somewhere close, but if not, factoring in the additional cost of bringing the dealer to your place, putting them up, paying some hourly charge, etc. is significant and takes the price well above the advertised retail price. At these pricing levels, maybe that incremental expense is just round off error, but it is disappointing. Maybe Spectral has or will back off of that (I hope so), but that was the word I heard from my dealer (and confirmed by others here with other dealers), who has been great throughout the process.

And, I think you are completely right on the cabling--I would not economize on the cabling with the Spectral system. Doesn't mean it has to be the stratospheric pricing at the top of the line (which I either cannot afford or at least have a hard time justifying), but I would bite the bullet and buy very good cables with such a system as you have. I'm sure the same holds true with the top of the line amp, probably more so as you suggest.

Thanks for a great write up and congrats!

 

[Steve Williams]

Russ - congrats on the search and a very successful outcome. I'm a recent Spectral convert too from end-to-end (I bought the 360 monos because I liked the monos in my room architecture and to drive my speakers, but the 260 was equally spectacular when I heard it). I have not had a chance to hear the 400s but the other factor in play here on the pricing (as I understand it), is that the 400s require dealer setup and installation at the buyer's expense. That's all fine and manageable if you are in Boston, SF, LA, Delaware, or somewhere close, but if not, factoring in the additional cost of bringing the dealer to your place, putting them up, paying some hourly charge, etc. is significant and takes the price well above the advertised retail price. At these pricing levels, maybe that incremental expense is just round off error, but it is disappointing. Maybe Spectral has or will back off of that (I hope so), but that was the word I heard from my dealer (and confirmed by others here with other dealers), who has been great throughout the process.

And, I think you are completely right on the cabling--I would not economize on the cabling with the Spectral system. Doesn't mean it has to be the stratospheric pricing at the top of the line (which I either cannot afford or at least have a hard time justifying), but I would bite the bullet and buy very good cables with such a system as you have. I'm sure the same holds true with the top of the line amp, probably more so as you suggest.

Thanks for a great write up and congrats!

I could never understand the manufacturer's mandate that an amp be set up by the dealer. What's the rocket science to attaching an IC to the amp and plugging it in. When I had my ARC Ref 600 Mk lll's I sold them to buy their replacement 610T only to get the same orders from ARC.

As much as I wanted the amp, I canceled the order and went in a different direction and bought my Lamm ML 2.1 and now the ML3 which were plug 'n play (just like the 610T)

 

[Mobiusman]

Russ - congrats on the search and a very successful outcome. I'm a recent Spectral convert too from end-to-end (I bought the 360 monos because I liked the monos in my room architecture and to drive my speakers, but the 260 was equally spectacular when I heard it). I have not had a chance to hear the 400s but the other factor in play here on the pricing (as I understand it), is that the 400s require dealer setup and installation at the buyer's expense. That's all fine and manageable if you are in Boston, SF, LA, Delaware, or somewhere close, but if not, factoring in the additional cost of bringing the dealer to your place, putting them up, paying some hourly charge, etc. is significant and takes the price well above the advertised retail price. At these pricing levels, maybe that incremental expense is just round off error, but it is disappointing. Maybe Spectral has or will back off of that (I hope so), but that was the word I heard from my dealer (and confirmed by others here with other dealers), who has been great throughout the process.

And, I think you are completely right on the cabling--I would not economize on the cabling with the Spectral system. Doesn't mean it has to be the stratospheric pricing at the top of the line (which I either cannot afford or at least have a hard time justifying), but I would bite the bullet and buy very good cables with such a system as you have. I'm sure the same holds true with the top of the line amp, probably more so as you suggest.

Thanks for a great write up and congrats!

Thanks for the very kind comments and congratulations on your recent acquisitions. One of the problems with Spectral stems from a well known maxim in the psychiatric circles (I am a psychiatrist as if you could not tell)--- brilliance and craziness are frequently next door neighbors. Unfortunately one of the ways brilliant less than centered people function is that they form rigid black white guidelines because they need them to function on a daily basis. Spectral is certainly an example of this and they have mandated this approach as a requirement to be one of their cherished dealers.

While I learned that MIT networks are essential to mine the incredible potential, and I mean incredible, for those of you who do not have first-hand experience with these absolutely remarkable products, some of the Spectral mandates are little more than mandates that do not have engineering or sonic black/white merits. If you are in the NYC/NJ area, stop by and hear what my system sounds like with an "enemy" tubed preamp. It is just amazing and as I said, in my opinion superior to the Spectral gospel. As I write this, I realize that what I am trying to say is trust your own ears and what you like.

I cannot for the life of me understand why the dealer needs to set up 400's because these products do not sound good for close to 10 days AND there are no adjustments that can be made by dealers or customers. I think it is to insure that the associated equipment, especially cables are done according to the gospel from Sunnyvale and a way to give the dealers a bit more profit when they are limited to 1 pair of 400's/month. Besides most of us who shop in the upper realms of a category have long left the price/value proposition out of the equation.

Most important, I listen more than I ever have and enjoy it more, which is why I got into this in the first place and then somehow insidiously lost my way as I learned to be discontent when something allegedly better came along. One of my main reasons for going to CES in addition to seeing what's new, is to remind myself how full of crap most of the companies and dealers in this space have become. Sadly politics has now become more important than ethics. Bullshit and reputation rule and most rooms at CES make you scratch your head and ask what are they thinking.

One of the most important moments for me in audio was sitting in Harry Pearson's main listening room talking with him about what happened to the Absolute Sound and the industry in general. The man genuinely cares about music and is inherently politically naive, (a compliment BTW Harry). Now we have leading magazines that only say nice things and many times directly in return for advertising revenue. I no longer subscribe to Stereophile and read Absolute Sound only about 1/2 of the time.

 

[edorr]

Speaking of Spectral heresy. The 360 poweramps are on my watchlist, and if I can ever get my hands on a reasonably priced used pair, I would certainly consider buying them. However, I have transparent reference cabling and have been wondering if these can be calibrated for the spectral amps. I asked Transparent, and they said - sure, we have many Spectral owners using our cables. Any thoughts / comments on this? I can't imagine the filtering in the network boxes on the Transparents is that much different than the on the MITs.

 

[Mobiusman]

Karen Sumner used to distribute MIT cables and then, the story goes, stole the idea and sufficiently modified it to stay clear of a suit. I know that there are fundamental differences between the two and that Spectral uses MIT's as part of their design. I would call Spectral.

I do not know specifically, but allegedly the 360 series 2 is quite an improvement from the series 1 with regard to sound and sadly price. From what I can tell, the 260 is substantially better than both, but there is no discount and the price is $10k, certainly less than a series 2 and probably more than a series 1.

 

[edorr]

Karen Sumner used to distribute MIT cables and then, the story goes, stole the idea and sufficiently modified it to stay clear of a suit. I know that there are fundamental differences between the two and that Spectral uses MIT's as part of their design. I would call Spectral.

Given the history between transparent and MIT, and the relationship between spectral and MIT, the chances of getting a straight answer to that question from Spectral are slim. I don't blame them .... I think my best bet would be to find someone that is actually using spectral with transparent cabling and has compared this with MIT cabling himself. Transparent may be able to track someone down among their client base.is

I do not know specifically, but allegedly the 360 series 2 is quite an improvement from the series 1 with regard to sound and sadly price. From what I can tell, the 260 is substantially better than both, but there is no discount and the price is $10k, certainly less than a series 2 and probably more than a series 1.

The fact that used current model spectral gear fetches about 80% of retail speaks volumes about its value. What makes you think the 260 is better than the 360 mkII. The latter is twice the prices.

 

[Mobiusman]

Given the history between transparent and MIT, and the relationship between spectral and MIT, the chances of getting a straight answer to that question from Spectral are slim. I don't blame them .... I think my best bet would be to find someone that is actually using spectral with transparent cabling and has compared this with MIT cabling himself. Transparent may be able to track someone down among their client base.is



The fact that used current model spectral gear fetches about 80% of retail speaks volumes about its value. What makes you think the 260 is better than the 360 mkII. The latter is twice the prices.

Out of the mouth of Spectral111111 I do not want to offer names but let's just say an old acquaintance at Spectral had an offline conversation and validated that the 260 is truly one of the best products they have ever built, probably the best on the amp front prior to the 400's and that the main difference between the 400 and 260 sonically is in the base. Clearly the 400 is more powerful, but using the wrong speaker wire, as I discovered, will more than negate the extra power not to mention the sound.

 

[edorr]

Out of the mouth of Spectral111111 I do not want to offer names but let's just say an old acquaintance at Spectral had an offline conversation and validated that the 260 is truly one of the best products they have ever built, probably the best on the amp front prior to the 400's and that the main difference between the 400 and 260 sonically is in the base. Clearly the 400 is more powerful, but using the wrong speaker wire, as I discovered, will more than negate the extra power not to mention the sound.

It would strike me as highly peculiar if out of two current model ampliers from the same manufacturer the $10K stereo amp is better than the $20K monoblocks, but it is certainly conceivable. Even at $10K, the 260 would be a screaming bargain. They sell used for around $8,000 and it is certainly very tempting to pick one up if it shows up used for that price.

I would have to be sure they work well with (recalibrated) Transparent cabling, because getting MIT cables is not in the cards....

How much heat does this amp generate? It would have to move into a rack with a few inches ventilation space above it?

 

[Mobiusman]

The amount of heat is directly related to the output demand. I would not call it a hot amp, but is certainly hotter than a Bryston 4B SST2 being pushed hard. I have about 1 1/2" above mine. Be careful because the operation temp is clearly part of the protection algorithm.

 

[marty]

I could never understand the manufacturer's mandate that an amp be set up by the dealer. What's the rocket science to attaching an IC to the amp and plugging it in. When I had my ARC Ref 600 Mk lll's I sold them to buy their replacement 610T only to get the same orders from ARC.

As much as I wanted the amp, I canceled the order and went in a different direction and bought my Lamm ML 2.1 and now the ML3 which were plug 'n play (just like the 610T)

Steve,
I don't think you've got that quite right. The Lamms are a true "plug and play" design. The ARC 610 were a "plug and maybe play design"! Both my 610s blew up the first week I owned them. Never again, dear ol' ARC. Preamps? Sure. Amps? You gotta be kidding For really high powered tube amps, think VTL. As perverse as it sounds, blowing a tube in the Siegfrieds was a pleasure. Replace the tube and push a couple of buttons and you're up and running again in under 2 minutes.
Marty

 

[Steve Williams]

I remember your incident all too well. Still makes no sense for dealer set up.

 

[KeithR]

I remember your incident all too well. Still makes no sense for dealer set up.

since Spectral gear is not discounted (as I recall), I'm not sure how this isn't included in the retail price anyways.

 

[Elliot G.]

Speaking of Spectral heresy. The 360 poweramps are on my watchlist, and if I can ever get my hands on a reasonably priced used pair, I would certainly consider buying them. However, I have transparent reference cabling and have been wondering if these can be calibrated for the spectral amps. I asked Transparent, and they said - sure, we have many Spectral owners using our cables. Any thoughts / comments on this? I can't imagine the filtering in the network boxes on the Transparent s is that much different than the on the MIT's.

Gentlemen, There are many differences in the way the cables are made with these two companies. They both do believe in using networks however that is where the similarities end. There are reasons to use networks on wires since all cables operate as filters. How this is done is different with Transparent and MIT. I can't speak for what Spectral is doing these days since I have not been a dealer for quite a while and I had my issues with the way they try to control everything that a dealer does.
Transparent does not use multigage wires which MIT does. Transparent calibrates the cable by length and by component which is not the case with MIT.
I know there are a few more differences however I am not technical enough to explain them they both make quality products and like many things in audio they are certainly system dependent.
Edorr be careful what you do the Spectral folks can be less than tolerant of the non believers, a word to the wise.
In my own experience there is significant differences in these two companies particularly when using tube gear. I dont care for the MIT at all and I think the transparent works really well.