Are these Furman strips worthy?
It’s all I could really afford.....mainly needed surge protection, but sound does seem a little smoother with it in place. Not obvious night/day difference.....could even be that pseudo effect y’all go on about.
It’s all I could really afford.....mainly needed surge protection, but sound does seem a little smoother with it in place. Not obvious night/day difference.....could even be that pseudo effect y’all go on about.
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Are these Furman strips worthy?
It’s all I could really afford.....mainly needed surge protection, but sound does seem a little smoother with it in place. Not obvious night/day difference.....could even be that pseudo effect y’all go on about.
if you look inside you won't find much. Typically the outlets are wired in parallel and 1 or 2 MOV's soldered across the line. The MOV's clamp at something like 600V so they won't be stressed by the UL tests (and not suppress much except the worst case surges). it may also have some line to line and line to ground caps. Thats an upgrade ofer the earlier Furman products.
The benefit of having all the power pass through a single point is not to be ignored. it reduces the differential chassis voltages that may arise if different paths are used for power. I suspect the common mode leakages in systems are the biggest quality aggressors. Isolation transformers are a good fix but not always enough. I personally do not like the classic input power filters on audio products because they introduce leakage to the chassis. The power transformer has enough leakage to be troublesome.
You're confusing power transformers (the topic of current discussion), running at 50/60Hz and their output (usually) going through full-wave (or sometimes half-wave) rectifiers, into large electrolytic capacitors for filtering out the 50/60/100/120Hz and harmonics to give a fairly constant DC source, often followed by voltage regulators to give near-absolute constant DC power, for powering audio electronic devices and systems ...Some people pointed to me on several occasions that transformers are less linear compared to resistors and capacitors, that's all.
So you are the level headed guy are you? I've met others with bad aversion to magnetics. Seems to me they consider those using signal transformers as 'dark side followers'. I don't care, I'd use whatever the setup needs to meet the requirement.
... with audio signal transformers, often used in microphone preamps and between audio equipment to eliminate ground loops or even to intentionally add a "transformer sound" to an audio signal. When used for passing audio, it's indeed noticeable and important that a transformer is "less linear" than a resistor or capacitor.
But power transformers have substantially MORE non-linearity than audio transformers, and no one cares because it doesn't make a difference because the output goes through this horribly awful distortion-inducing rectifier stage that (if everything works right) no one hears. The core type and windings are chosen using very different parameters.
I think anyone who cares about good audio hates these things. It's not just on audio products, it's everything with a ground prong. You can make your own equipment that has no (intentionally added extra) capacitance between the ground and either the hot or neutral, but something else plugged in surely has a filter and will pollute the ground connection anyway.
There’s a bunch inside including a toroidal transformer.
it actually sets off on a power blink which none of my other surge strips haveYouTube
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Perhaps a torroidal common-mode choke. Series inductors are common too. Some discussion about power filters: Power Conditioning & Power Cables
Also:https://www.soundpro.com/catalog/documents/ADP-1520B_brochure.pdf
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Its a.major upgrade from earlier Furman stuff. The circuitry looks like Panamax (same parent).
Daniel, I was confused as well with what Indra1 was getting at as well.
What I don't get is why put isolation transformers on the low level stuff and not on the high power stuff. Would seem to be only doing half the job, and if a job is worth doing etc.
I'll stick with batteries for the low level stuff...
What I don't get is why put isolation transformers on the low level stuff and not on the high power stuff. Would seem to be only doing half the job, and if a job is worth doing etc.
I'll stick with batteries for the low level stuff...
I can relate our approach which may or may not be applicable to your own situation. We install either Sola or Eaton high-current TVSS units pre-isolation transformer in order to limit peak voltage surges. We also use an isolated ground approach to limit ground differentials.
We ban any power strips like most Furmans with surge protection downstream from the isolation transformer in our studio installs. The most common form of surge protection involves MOVs which can range as much as several nF of capacitance each, and many have paralleled MOVs to increase surge amperage. This can couple noise from attached gear into the isolated ground system. In addition, the surge limit function is already addressed upstream so it is unnecessary.
In a home situation a surge limiter utilizing MOVs should be placed at the main power panel where all incoming utilities should be bonded. This way any noise it couples into the ground will be common to all ground and neutral connections in the system and not cause differential currents to flow between different chassis, cable TV, antenna coax, etc.
The Monster HTPS-7000 utilizes fused MOVs pre-isolation transformers as it should. If you examine the topology of the unit, you will have to credit Richard with for designing the most effective passive power conditioner which (used to be) commercially available for home use. It is certainly the most effective one I have used and have installed in small studios. The isolated outputs have both common and transverse mode filtering post-isolation which is highly effective. The only filters I have used which achieve similar results for whole studio power filtering cost over $2000 just for the filter section. The passive approach is of course different from the active sine regeneration units like the PS Audio which cost far more and afford stabilized voltage and frequency to boot, albeit at the cost of added complexity and perhaps reliability compared to a passive unit.
This subject is similar to the cable issue in that the better the equipment and system is designed, the less of an deleterious effect is seen from the use of poor power or cables. This is not just my opinion, it is my experience. Fully broadcast quality analog gear has shielded power transformers and often input and/or output transformers and will not cause ground loops or couple power line common-mode noise. Consumer and pro-sumer gear has to hit a much, much smaller price point (other than boutique gear) and use the cheapest power transformers and have no input or output transformers, and are usually susceptible to the pin 1 problem to boot. I am not saying transformers are the only way to keep inter-chassis noise currents from flowing, but that they do with many tens or hundreds of megohms of galvanic isolation. edit: And many dB of common-mode isolation.
As usual there is no such thing as a free lunch.
Cheers,
Howie
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While it would certainly be great to put AC isolation on the high-power loads like power amps like we do in our studio systems, in order to handle a 300W/chan amp the transformer would have to be rated at over a KW and be huge and $$$, making it not reasonable in a unit for home use.
The reason it is not absolutely necessary in an average home audio system is because the point of the power isolation is to separate AC power common-mode leakage paths from the audio paths and the iso-xfmr (if wound accurately) nulls out the AC common-mode currents. If the one power system point directly connected to the mains is the non-isolated high-power AC outlet where the amp is plugged in, then there is still no AC common-mode path paralleling the audio cabling between the low-power or amp equipment.
Cheers,
Howie
I was referring to electrostatic shielding between primary and secondary.
Cheers,
Howie
Huh......may have possibly figured out why my parasound Hint sounded ‘slow’
That forum thread mentioned when connecting to straight power vs a series filter conditioner that it seemed like the amp had a higher slew rate.
Something to try because I’ve never used the hint without the Furman.
Just got the hint back from being checked (authorized service center)yesterday so that tidbit of info comes in handy for sure. They found nothing wrong besides a known defective volume pot.
Thanks Mark
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Howie,
On my size systems, inside a rack even unbalanced is okay. Between racks in the same room and circuit panel, electronically balanced is used. Between rack rooms or different AC power panels audio isolation transformers are always used.
The consultants who design systems have given up on the issue and just specify digital audio for every possible interconnection and then have a duplicate system for back-up.
The master control room audio system whenever possible is an isolation transformer.
All power is 208 volt Y.
It is not unusual to have an amplifier room circuit breaker panel rated for 200 amps 3 phase Y 208 volts. Of course these must be motor rated breakers to handle the current surges!
Then there was the place with electronic load sensing breakers. The electricians installing them set the trip point wrong. Destroyed the breakers and caused a system failure.
On my size systems, inside a rack even unbalanced is okay. Between racks in the same room and circuit panel, electronically balanced is used. Between rack rooms or different AC power panels audio isolation transformers are always used.
The consultants who design systems have given up on the issue and just specify digital audio for every possible interconnection and then have a duplicate system for back-up.
The master control room audio system whenever possible is an isolation transformer.
All power is 208 volt Y.
It is not unusual to have an amplifier room circuit breaker panel rated for 200 amps 3 phase Y 208 volts. Of course these must be motor rated breakers to handle the current surges!
Then there was the place with electronic load sensing breakers. The electricians installing them set the trip point wrong. Destroyed the breakers and caused a system failure.
Well put. For any given suite consisting of a control and tracking rooms we distribute a single phase 120, but if more than one power source is used, digital transport or transformers are used. We had one install in a multiple suite studio complex where sets of Jensen JT11s which were deemed to be sonically superior to the digital link they replaced, so there another data point with several undefined variables such as digital link ground connections, bit depth, etc...
Especially for most broadcast studios these days AoIP (Audio over IP) is used and there is almost no analog transport. The balanced line-ins in a Wheatstone Wheatnet system for instance use XLR to RJ45 dongles...and everything else is Cat6 hither, thither and yon.
We still do a lot of analog recording studios, largely because of the lure of legacy...many even still have 2" tape machines! Some have multiple suites and tracking rooms...those studios get the most elaborate power systems.
Fun...
Howie
Howie -->
During development of the circuitry I made a change which improved CMR to well over 100dBv over a wide BW.
See change here and is what you get with -7000. My before and after data;
View attachment CMR trans 7000.pdf
THx-RNMarsh
During development of the circuitry I made a change which improved CMR to well over 100dBv over a wide BW.
See change here and is what you get with -7000. My before and after data;
View attachment CMR trans 7000.pdf
THx-RNMarsh
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