Input cables for Spectral preamps?

[twitch]

David, my reference was made in somewhat of a comparison to a situation years ago when a certain snowmobile manufacturer was insisting that 'their' brand of oil to be used in order to maintain the engine warranty even though other brands had oil that met spec. Simply put, when that happens the manufacturer becomes obligated to provide the oil !

Thus my reference to the Spectral / MIT cable thing.

 

[acousticsguru]

David, my reference was made in somewhat of a comparison to a situation years ago when a certain snowmobile manufacturer was insisting that 'their' brand of oil to be used in order to maintain the engine warranty even though other brands had oil that met spec. Simply put, when that happens the manufacturer becomes obligated to provide the oil !

Thus my reference to the Spectral / MIT cable thing.

First of all, "oil" for an engine sounds much like a snake-oil argument and hardly a technical inevitability, secondly, MIT is not "their" but an independent brand, and thirdly, Spectral do provide their "Spectral"-branded MIT cables which theoretically speaking they could include along with their product for a price (if you take them by their word, it's as if that were fact anyhow - they do not make believe their products to be cheaper than they are misinforming the customer, on the contrary, all you ever hear is one must use the appropriate cable to prevent damage), if forced to do so, the only difference would be that we customers would additionally suffer from it in no longer being able to upgrade within the MIT (e.g. Oracle) line of cables. A "set price" might keep some customers from buying their product (but only customers who willingly ignore what they're being told all along), but the technical necessity for power amps can't be argued.

But, to reiterate, Spectral isn't MIT, and it does appear they're conscious of pricing (e.g. Oracle Matrix 50 was one of three interconnects designed along with the second-to-latest and latest generation of Spectral amps and approved by Spectral, even so, they chose the more moderately priced HD 36 and HD 23 as UL-350III and UL-230III). I have little doubt that if they owned MIT, the cables would be priced more moderately to suit the pricing of their electronics (having said that, the latter have gone up noticeably in price for the latest generation, at least here in Europe, hardly an effect of the exchange rate).

Personally, being a Spectral customer myself, I've always thought of electronics plus cabling as a "set price" for exactly this reason. What I do like about it is one doesn't misspend money trying to mix and match cables as with most other brands (been there, done that) - it effectively saves money to know what one needs (and really wants, as they're designed together) to get to achieve the intended result versus having to try and find out by trial and error.

Greetings from Switzerland, David.

 

[twitch]

OK, so tell me......what is the 'appropriate cable' ? specs ?

 

[acousticsguru]

OK, so tell me......what is the 'appropriate cable' ? specs ?

I'm not a cable designer. Read this?

http://www.mbl.de/wp-content/uploads/2014/10/Wiring-high-bandwidths-amplifiers_EN.pdf

Greetings from Switzerland, David.

 

[Speedskater]

In that paper, points 1 & 2 are important, while point 3 is incorrect.

 

[acousticsguru]

In that paper, points 1 & 2 are important, while point 3 is incorrect.

Could you go into more detail? I've invariably been told that running low frequency cables in parallel with power cables, digital cables and/or loudspeaker cables is a no-go.

Greetings from Switzerland, David.

 

[AL1973]

Now wondering, of course, who does this (i.e. use something else on their Spectral preamp's input side), and what are your findings? Experiences?

Greetings from Switzerland, David.

Me!
I remember 2C3D where Spectral-Avalon-MIT-ASC cooperated...could be this the reason?
Use only MIT on Spectral is like a "urban legend", you can use most of cables in commerce. I had in the past, Spectral DMC 12 + DMA 90, DMC 15 + DMA 150S2 now against other "urban legend".... AGI 511 + DMA 150S2. I used MIT, Cardas, Audioquest, NBS and many others cables, no one gived to me any problem. Now i use DIY Cable made by mayself with surplus MIL cables. Both Speakers Cable and Signal Cable of course.

 

[acousticsguru]

Me!
I remember 2C3D where Spectral-Avalon-MIT-ASC cooperated...could be this the reason?
Use only MIT on Spectral is like a "urban legend", you can use most of cables in commerce. I had in the past, Spectral DMC 12 + DMA 90, DMC 15 + DMA 150S2 now against other "urban legend".... AGI 511 + DMA 150S2. I used MIT, Cardas, Audioquest, NBS and many others cables, no one gived to me any problem. Now i use DIY Cable made by mayself with surplus MIL cables. Both Speakers Cable and Signal Cable of course.

One can use whatever interconnect one likes, but be careful using non-MIT (or Spectral-branded) loudspeaker cables, in particular low inductance, as these may drive a Spectral power amp into oscillation. Not an urban legend, speaking from personal experience (frying a Spectral power amp using Kimber speaker cables - sounded silly-fast, but not worth the experiment…). My question was whether someone achieves good synergy using non-MIT interconnects with MIT loudspeaker cables. Normally, in non-Spectral systems, the tendency is (r at least used to be) to compensate, as low-capacitance interconnects are being used with low-inductance loudspeaker cables. In my experience that whole family of interconnects aren't an ideal match in a Spectral setup, of course all of this changes as soon as a Spectral preamp is used with a power amp by another brand.

Greetings from Switzerland, David.

 

[AL1973]

One can use whatever interconnect one likes, but be careful using non-MIT (or Spectral-branded) loudspeaker cables, in particular low inductance, as these may drive a Spectral power amp into oscillation. Not an urban legend, speaking from personal experience (frying a Spectral power amp using Kimber speaker cables - sounded silly-fast, but not worth the experiment…). My question was whether someone achieves good synergy using non-MIT interconnects with MIT loudspeaker cables. Normally, in non-Spectral systems, the tendency is (r at least used to be) to compensate, as low-capacitance interconnects are being used with low-inductance loudspeaker cables. In my experience that whole family of interconnects aren't an ideal match in a Spectral setup, of course all of this changes as soon as a Spectral preamp is used with a power amp by another brand.

Greetings from Switzerland, David.

Sorry David,
but I answered to your question. I use other cable, not MIT and I'm very satisfied on it. Your experience using Kimber cables, I know that if twisting wires (reduces inductance, increases capacitance) but you need very long cable to have a significant influence.
Of course your experience is yours!
What I don't understand is why you talk about speaker cable and in the last sentences about signal cables?
Anyway my esperience, i have a Spectral DMA150 S2 + AGI 511. Signal cable is 5mt. long DIY MIL Spec. Copper/Silver plated 2micron teflon isulation.
Speaker cable, 2 mt. long, is DIY Mil Spec. Copper/Silver plated 2micron teflon isulation, double wire NOT twisted, AWG 10. Speaker is Avalon Eclipse.
No problem in 3 years.

 

[acousticsguru]

Sorry David,
but I answered to your question. I use other cable, not MIT and I'm very satisfied on it. Your experience using Kimber cables, I know that if twisting wires (reduces inductance, increases capacitance) but you need very long cable to have a significant influence.
Of course your experience is yours!
What I don't understand is why you talk about speaker cable and in the last sentences about signal cables?
Anyway my esperience, i have a Spectral DMA150 S2 + AGI 511. Signal cable is 5mt. long DIY MIL Spec. Copper/Silver plated 2micron teflon isulation.
Speaker cable, 2 mt. long, is DIY Mil Spec. Copper/Silver plated 2micron teflon isulation, double wire NOT twisted, AWG 10. Speaker is Avalon Eclipse.
No problem in 3 years.

The Spectral requirement (as per warranty) is to use MIT (or Spectral-branded MIT) loudspeaker cables to keep power amplifiers from oscillation (I can only emphasize that this isn't hearsay or urban legend, but happened to me personally). As to the cable length, according to the information I got when the amp had to be repaired, that doesn't appear to be the problem at all, but the absence of a choke (or low-pass filter) to block radio frequencies (also, MIT cables appear to be designed to keep energy from reflecting back into the amp). My question at the time was about what alternative brand interconnects audiophiles use in their Spectral setups since there is no requirement there. In the meantime, I have never heard a combination of different brand interconnect with MIT loudspeaker cable sound as good as using a full loom.

Greetings from Switzerland, David.

 

[AL1973]

The Spectral requirement (as per warranty) is to use MIT (or Spectral-branded MIT) loudspeaker cables to keep power amplifiers from oscillation (I can only emphasize that this isn't hearsay or urban legend, but happened to me personally). As to the cable length, according to the information I got when the amp had to be repaired, that doesn't appear to be the problem at all, but the absence of a choke (or low-pass filter) to block radio frequencies (also, MIT cables appear to be designed to keep energy from reflecting back into the amp). My question at the time was about what alternative brand interconnects audiophiles use in their Spectral setups since there is no requirement there. In the meantime, I have never heard a combination of different brand interconnect with MIT loudspeaker cable sound as good as using a full loom.

Greetings from Switzerland, David.

Of course David, in Spectral Manual you can find the section "choice of cables" where if you read carefully they don't write exactly "if you don't use MIT/Spectral cables you are out of warranty". They suggest to use it and they say "use improper cables" will not be covered under factory worrenty.
Anyway, you can use Trasparent that use similar MIT network in speaker cable.
In Italy there is Acustica Applicata that sell Avalon, powered by Spectral, and often to advertise their product they use De Antoni cable. De Antoni are made in aluminum without any network inside.
Below my Spectral without MIT/Sectral/Trasparent Cables and without Spectral preamp! I listen only vinyl and AGI 511 as got one of the best phono preamp at honest cost.