Monoblocks - near speakers or not?

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PaulFolbrecht

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Monoblocks - near speakers or not?
« on: 8 Jun 2006, 10:15 pm »
Is it better to have long interconnects/short speaker cables or vice-versa?

I've always kept my monos on a rack with 1M interconnects.  Rationale is that it is better to have a short run where signal level is low - preamp to amp - than high - amp to speaker.

I realize that many ppl put the amps right next to the speaker but I don't see how this could be advantageous.

Well, complicating the issue for me is that my main system is also my HT system and there is a TV between (but BEHIND) the speakers.  My rack's off to the side, and I'd need espcially long interconnect to reach the left speaker (like 3M).

TheChairGuy

Monoblocks - near speakers or not?
« Reply #1 on: 8 Jun 2006, 11:08 pm »
I'm of the camp that low level signals should have to travel less far than high level signals. Low level signals have more (proportionally) to lose along the way.

There is no lower level signal than a phono cartridge output in audio - clearly, the shortest and least truncated transmission line pays off rich dividends there.

So, short IC's and longer speaker cables, in general,  for me.

WEEZ

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Monoblocks - near speakers or not?
« Reply #2 on: 8 Jun 2006, 11:16 pm »
To me, it would depend on your pre-amp. If the ouput impedence is high and/or it's output stage is low on current drive, I would stick with short interconnects and longer speaker wires. The thought being, that this scenario would minimize the capacitance the pre-amp would need to plow thru.

There are many opinions on this subject, and the above is not an absolute. Many users of tube amplifiers like short speaker wires to maintain a slightly higher damping factor.

You might try to borrow some varying lengths of IC's and speaker wires so you can try both options; or check with the maker of your amps for a recommendation.

IMHO, get the TV out of the system altogether. Whichever wire option you choose will sound better than having the TV in the mix. Just did that myself, recently, and believe me, despite the rage over home theater...if you value your music, separate your video stuff from your audio stuff. You will thank me when you do. Really. That damn TV is messing up your imaging.  :(

WEEZ

Bob Reynolds

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Monoblocks - near speakers or not?
« Reply #3 on: 8 Jun 2006, 11:24 pm »
I believe the rationale for longer interconnects and shorter speaker cable is based on the amount of current and thus the potential IR drop across the wire.

While it's true that line level signals are more prone to contamination as a percentage of the signal, that issue is managed with balanced interconnects made from shielded twisted pair cable.

-- Bob

_scotty_

Monoblocks - near speakers or not?
« Reply #4 on: 9 Jun 2006, 12:06 am »
I have had no problems with a custom pair of 19ft. long IC's from Reality Cable between my buffer and my amp which is between my speakers.
The buffer has a 27ohm output impedance and is not affected distortion issues from such a load. The cable appears to be on the  moderate side for
capacitance per foot and I have encountered no loss of highs with this setup.
The amplifier input is about 33kohms. I think your success with long cables
is a direct function how well your preamp can drive the cable run and the magnitude of the lowpass filter that may be created by the cable capacitance.
Scotty

PaulFolbrecht

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Monoblocks - near speakers or not?
« Reply #5 on: 10 Jun 2006, 04:25 am »
Weez -

1) I know nobody with ICs over 1M
2) There is no opposite wall (open-concept house) so I really don't think the TV is hurting much, if anything.  It's thin - LCoS - and almost 12" behind the speakers.

Bob - I don't have balanced equip, so can't run balanced ICs...

Not hearing much enthusiasm here for even tryings the long IC/short speaker cable route, so I think I'll forget it again.. for now.

Bob Reynolds

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Monoblocks - near speakers or not?
« Reply #6 on: 10 Jun 2006, 05:00 am »
Paul - depending on the speakers, shorter cable may not be of much sonic benefit anyway. E.g. monitors that are high-passed will never see any bass signal so they can use much smaller wire or longer cable with no degradation. Another approach to getting the same effect as short speaker cable is to use double runs. One set of cables with spades and one set with bananas will cut the resistance in half.

Just an FYI concerning unbalanced connections... You can use input and output audio transformers to convert unbalanced to balanced and then back again. One such inexpensive product is made by Rane, called the Balanced Buddy. Another more expensive option is made by Jensen. I use a Jensen output transformer to convert the single-ended outputs of my Arcam FMJ CD23T player to balanced.

-- Bob

JLM

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Monoblocks - near speakers or not?
« Reply #7 on: 10 Jun 2006, 09:52 am »
Convention, and the offerings of most cable manufacturers, suggest shorter interconnects and longer speaker cables.

I have monoblocks too in a nearfield set-up.  My Element cables come standard with 2 ft interconnects and 7 ft speaker cables.  I recall reading somewhere years ago that these are the ideal lengths (and the ideal ratios), but can't remember why.

NealH

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Monoblocks - near speakers or not?
« Reply #8 on: 10 Jun 2006, 02:36 pm »
Interconnects are easier to compensate for in regards to length.  Design and construction techniques such as balanced, twisted, shielded, materials, etc. all provide the capability to handle length while mitigating the typical issues associated with length (RF susceptibility, signal loss, reflections, response errors, etc).  

This is not so much the case with speaker wires.  The reactive effects of some wires due to their design, construction, placement and/or length has the potential to upset the power stage of an amplifier.  Amplifiers often incorporate feedback for better control of bandwidth, linearity, distortion, and a host of other parameters and, this can just as easily exacerbate stability issues as it can mitigate them.  Most mainstream amplifiers are, of course, very stable today when used with wire lengths typically found in stereo or home thearter playback.  So whether we are talking 2' or 10' is not likely to make a lot of difference.  

However, stability and amplifier performance should be a concern in stereo playback when some of the more uniquely, or radically, designed cables are connected to audiophile or esoteric amplifiers, such as the OTL variety.  These amplifiers most often compromise on the side of sonics when making their design decisions.  The potential issues here can be mitigated by making the speaker wires as short as possible.   Ideally, we don't want any wire between the high current output stage of the amplifier and, the speaker terminals.  

The growing XLR number resulting from lengthening speaker wires can also pose issues with the speaker crossover network which can affect the response characterisitics of the speaker.  In some speakers, due to the crossover, it doesn't take much added resistance to start impacting the response.  For instance, a 1 ohm resistor in series with the Magnepan speaker will give the impression of adding "bloom" to the midrange by  slightly altering the response.  This is also the case with many other speakers.  As a matter of fact, this is why Carver added the "tube" output feature to his amplifiers once upon a time.  The 1 ohm resistance was suppose to mimic the typical output resistance of a tube amp.  Of course the Carver approach only povided a static element while, in a tube amp the plate or output resistance is dynamic so the results will never be exactly the same.  While the ultimate resistance exibited by most of the speaker wires that we use will be quite a bit less than 1 ohm, the fact remains that it can alter the speaker response.  We all have our thresholds as to what difference we can tolerate.  

RF susceptibility is another reason that one needs short wires, especially with speaker wires.  Wires function very well as antennas and, the output stage of amplifiers can be vulnerable to this noise since manufactures often put as few filtering components in the power signal chain as they can get away with.  After all, from a sonic standpoint less is often better here.  Not the case when dealing with RF though.  

In a perfect world we want all our wires as short as possible - interconnect and speaker.  However, in our rather imperfect world when it can only be one, my vote goes to making the speaker wires as short as possible.

meilankev

Monoblocks - near speakers or not?
« Reply #9 on: 10 Jun 2006, 03:09 pm »
Paul,

I'm one of those who has my tube monoblocks sitting on the floor right next to the speaker they are driving.  If I instead had a single stereoblock, I would also sit it on the floor directly between the speakers.

My preamp (and all source equipment) sit as far back in the rear corner as possible, and I use a long run of balanced interconnects between the preamp and monoblocks (hidden behind the drywall).

If my preamp wasn't balanced, and I had to use unbalanced cables with RCA jacks, I might not have gone this way.  I don't know.

Good luck to you!!!
Kevin

PaulFolbrecht

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Monoblocks - near speakers or not?
« Reply #10 on: 10 Jun 2006, 03:55 pm »
I haven't looked into it, but I don't wanna think about what a LONG (3M), high-quality pair of balanced ICs cost...

Dan Banquer

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Monoblocks
« Reply #11 on: 10 Jun 2006, 06:22 pm »
The answer to your question is yes, and right behind the speakers if you have the room to do so.
BTW: Good quality interconnect cabble does not have to be expensive.
             d.b.

PaulFolbrecht

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Monoblocks - near speakers or not?
« Reply #12 on: 10 Jun 2006, 06:25 pm »
Ok, some more opinions, please:

1) Do long ICs have to be balanced?  How will 3M unbalanced perform?

2) SPECIFIC RECOMMENDATIONS on brands for longer ICs?  Low capacitance?  I have some rather expensive Wireworld Polaris 1M ICs... I'm not spending what they're asking for 3M.

andyr

Monoblocks - near speakers or not?
« Reply #13 on: 11 Jun 2006, 03:26 am »
Quote from: PaulFolbrecht
Ok, some more opinions, please:

1) Do long ICs have to be balanced?  How will 3M unbalanced perform?

2) SPECIFIC RECOMMENDATIONS on brands for longer ICs?  Low capacitance?  I have some rather expensive Wireworld Polaris 1M ICs... I'm not spending what they're asking for 3M.
Hi Paul,

I think you commented in an earlier post that you didn't know anybody using more than 3m ICs ... weeell, my shielded, unbalanced ICs are about 35' (11m) long due to the way I designed my "music room" (speakers up one end, flanking a window looking into the garden and LP storage cabinet and source components at the other end of a 27' long room).   :o

I have 3 monoblocks behind each of my Maggie IIIa speakers - the IC connects my preamp to each 3-way active crossover.

If you have a low output impedance preamp (<200 ohms) and a high input inpedance active Xover / power amp (my active Xovers are 100K ohms) AND the preamp is designed to drive long ICs (ie. cope with high capacitance), you won't have any problems with long unbalanced ICs.

However, the longer they are, I suggest the more reason to need them to be shielded - and the shielding process can introduce nasty artefacts into the sound, unless it's done properly (and no, not all commercial cables are "done as properly as they should be"!!).    :D

NB: I don't think a "passive preamp" will cope well with long ICs!

As I understand it, in terms of R, L & C for an IC between a "real preamp" and an active Xover/power amp:

*  R is irrelevant, as there is only a tiny current flowing (in fact VdH make some supposedly-excellent carbon ICs which have very high resistance!).

*  L impacts minimally, again because there is so little current flowing.

*  C is important as too high C:
a) might be a problem for the output stage of the preamp, and
b) will roll off the highs if your Zout/Zin ratio is not big enough.  In my case, the ratio is 500 ... so I have little problem.

Naturally, any length of cable can be considered to produce a degradation but I think with ICs, if the rest of the gear is matched properly you can do minimum damage.

Whereas with speaker cable,  basically, R should be neglegible and the lower L, the better ... so shorter is better for a speaker cable.  The only amps I have come across which this "rule" does NOT hold for is old Naim power amps which I understand were designed to have the "impedance load" of 10 ft of Naim speaker cable attached to their output stages.

Regards,

Andy

PaulFolbrecht

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Monoblocks - near speakers or not?
« Reply #14 on: 11 Jun 2006, 04:51 am »
Andy,

Thanks for that great post.  Output imp. of my current pre (PrimaLuna 3) is 3500 ohms, giving a ratio of about 30.

Would that be a problem with 3M ICs???

Bob Reynolds

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Monoblocks - near speakers or not?
« Reply #15 on: 11 Jun 2006, 06:18 am »
Quote from: PaulFolbrecht
Andy,

Thanks for that great post.  Output imp. of my current pre (PrimaLuna 3) is 3500 ohms, giving a ratio of about 30.

Would that be a problem with 3M ICs???


My understanding is that a good rule of thumb is a ratio >=10 for Amp(Zin) / Preamp(Zout) to avoid any cable issues. Of course, I guess it depends on the cable.

BTW, a 10ft pair of balanced ICs from BlueJeans Cable costs less than $65. This is based on Belden's 1800F cable which has a capacitance of 13pF/ft.

Russell Dawkins

Monoblocks - near speakers or not?
« Reply #16 on: 11 Jun 2006, 07:01 am »
Whereas I use mostly short (2-3') interconnects, mostly unbalanced, I do have one pair 12' long, also unbalanced and nothing fancy (cheap Monster) that I must use for phono in my studio. Circumstances dictate that it traverses a veritable rat's net of power cords, and goes fairly near numerous "wall wart" power supply lumps. Only when it gets laid directly across one of these lumps (which are notorious emitters of EMI) do I get the slightest trace of hum - otherwise, no hum at all.

I do try to follow the general rule of whenever you have to cross an AC line, do it at right angles. Never run a low level signal line parallel with a line carrying high levels of AC, including speaker wires.

I am re-doing my studio monitor set up and have elected to go with the long IC short speaker wire approach - I may even find a way to situate the amp immediately under the stand mounted speakers to keep the speaker wires down to 2 feet or so. The line level interconnects will be balanced, I think, and about 12' feet long.

Speaking for myself, I am not sure at all that balanced sounds better than unbalanced unless hum is actually an issue.

Speaking still further for myself I would go with the Blue Jeans option and put the money saved into speaker/amp/music. Blue Jeans is good enough for me, but then I have long ago had to come to grips with the fact that I couldn't afford the "good stuff" when it came to buying multiple 50' microphone cables.

My compromize is to have one 35' pair of $10 a foot Monster mic cable which I use whenever I can for the most critical part of whatever I'm recording.  It actually does sound nice, but I had to make it and it cost me $700 (big bux to me) back in '91. I must admit, though, that I still wonder what silver mic cables would sound like.

andyr

Monoblocks - near speakers or not?
« Reply #17 on: 11 Jun 2006, 09:17 am »
Quote from: Bob Reynolds
Quote from: PaulFolbrecht
Andy,

Thanks for that great post.  Output imp. of my current pre (PrimaLuna 3) is 3500 ohms, giving a ratio of about 30.

Would that be a problem with 3M ICs???


My understanding is that a good rule of thumb is a ratio >=10 for Amp(Zin) / Preamp(Zout) to avoid any cable issues. Of course, I guess it depends on the cable.

BTW, a 10ft pair of balanced ICs from BlueJeans Cable costs less than $65. This is based on Belden's 1800F cable which has a capacitance of 13pF/ft.
Hi Bob,

Yes the "rule of thumb" is a minimum of x 10.  I personally believe x 50 would be better and while "x 10" removes most of any problems to do with capacitance, it does not take away all of them.  x 50 is kindof a "safety factor".

Given my preamp is a hybrid, having a unity-gain tube output stage which still has an output impedance of <200 ohms, I cannot understand why tube designers produce preamps with a Zout of 3,500 ohms?   :?   It just produces the potential to cause matching problems.

Paul, if you go for a low C design - with a low C of around 13pF/ft like the one Bob suggested (although I think you don't need/can't have balanced ICs) - a 3m IC shouldn't give you any troubles.  That is, assuming the Prima Luna is able to drive it (I have no idea!  :)  ).

Regards,

Andy

PaulFolbrecht

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Monoblocks - near speakers or not?
« Reply #18 on: 11 Jun 2006, 02:09 pm »
As for drive, I have a hard time believe any active pre couldn't drive 10'!  Though the PL 3 is a low-gain unit (11.5dB).

Any recommendations on really short (1M) speaker cable that's great for the money?  I see BlueJeans does speaker cable too...

Kevin Haskins

Monoblocks - near speakers or not?
« Reply #19 on: 11 Jun 2006, 02:19 pm »
If you have an all balanced system I'd say long interconnects & short speaker cable.  

If your system is single-ended I'd stick with long speaker cables due to the propensity of unbalanced inputs to pick up hum as they get longer.

High-end speaker cable tends to cost more than interconnects due to the quantity of materials needed.   That might make the long interconnect short speaker cable situation cheaper also.  

My favorite long-run interconnect is Cardas G-Master Reference which cost about the same as the Cardas Crosslink so its a bargain in the high-end audio world.   I prefer the Canare twisted pair for the working man's budget.