Official Wyred 4 Sound Amp Thread - Page 49

I have been told this is not generally a good idea, as it runs the current "through" the first speaker (and all its drivers, internal wiring, and crossover) to get to the second speaker.

Most Home Audio speakers are not designed for this, and they will not sound as good.

While series wiring is common knowledge it is more associated with the wiring of drivers in a multiple driver single speaker, not multiple speaker applications where quality sound is the goal.

Pro speakers used in speaker banks and speakers of that type "are" designed for using multiple speakers.

So I would check with your speaker manufacturer before wiring your speakers that way.

Even this little paragraph says it is not often a good idea SERIES

Unless there some issue in the crossover I can't see it being a problem but I guess the speaker company should know.

It's not a crossover issue, it's an implementation issue.

Besides, 2 centers in a home envirement is a bad idea anyway.

I understand you want the drivers in sync and thats why I reference the crossover. In large screen applications don't you often have multiple LCRs?

I might suggest you research exactly what is occurring when multiple driver Home Audio speakers are wired to each other in a series.

Unless they were specifically designed for that type of wiring it is a bad idea.

This type of wiring schematic is more applicable to MultiRoom Applications, Multi-driver or Dual Voice Coil subwoofers, and Car Audio, not 2 channel and HT type apps.

Can you recommend where? You make it sound like you've read something to support it.



How would that be any different? All power amps are comfortable at certain impedance, if the amplifier is within that impedance it does not care!! Volume controls for multiroom applications typically have impedance matching built in, car audio amps and subs are usually matched by power output and impedance. (In example voice coils and there impedance) Larger theaters run multiple surrounds off the same channels, in-wall sub amplifiers(multiple subs).

If your not running the amp wide open to get the volume your looking for I don't see the issue, if someone else knows better please inform me.

The link I posted above has this simple info:

How do you run speakers in series?

It is not suggested that you run speakers in series. No two speakers will be exactly identical, even if they are the same model from the same manufacturer. This means that they will act slightly different from each other when presented with the same input signal. When wired in series, these differences will cause distortion in the form of back EMF.
You can however run both coils of a DVC speaker in series. The cone movement for both coils will be identical, and will not cause distortion problems.
===================================================

As well also in that post I mentioned that some PRO speakers are often designed to be run in multiple speaker apps.

All you need to do is a good Google search and you will see that it is NOT generally considered a good idea if you're interested in high fidelity with common Home Speakers.

I am currently using the excellent BIC Venturi speakers. I am planning to replace them. I doubt they can handle anything exotic.

How would a Parasound Halo A51 and Sunfire TGA-7401 compare to a Wyred for Sound MC5x500? They are all roughly in the same price range.

I read a review where they stated that the SX-1000 (does it use the same modules as the MC5x500?) was far smoother sounding than the Parasound Halo A23. I thought Parasound amps were considered smooth sounding but in the review it was considered harsh and bright by the review.

You can view the SX-1000 vs. A23 comparision here: http://www.hometheaterhifi.com/power-amplifiers/power-amplifiers-reviews/wyred4sound-sx-1000-monoblock-amplifier/page-3-the-wyred4sound-sx-1000-monoblock-power-amplifier-in-use.html

Something wrong or is this true?

By the way, I have Klipsch speakers so I want something smooth sounding.

The SX-1000 uses the ICEPower ASP-1000 boards that are modified by W4S for better sound than the stock boards.

CORRECTION:
The MCNx500's DOES USE the ASP-1000 boards. W4S uses different naming conventions (8Ohm versus 4Ohm ratings) for their Multi-Channel amps and their Mono/Stereo amps.

FWIW, here is the B&O datasheet for the ASP-1000 boards (before modifications by W4S).

http://www.icepower.bang-olufsen.com/files/solutions/icepower1000aspdata.pdf
Edited by emailtim - 6/19/12 at 10:31am

Thanks but any comments/opinions on how the MC5x500 compares to the Parasound Halo A51 and the Sunfire TGA-7401?

Sorry, I have no experience with the Parasound or Sunfire.

CORRECTION:

I just checked the W4S website and stand corrected (got the model numbers mixed up) the MC5x500 uses the same ASP-1000 amp as the ST-1000 (570wpc into 8Ohms and 1140wpc into 4Ohms). I don't know why they named their multi-channel amps using the 8 Ohm rating and their mono-blocks and stereo amps using the 4 Ohm rating (seems a little inconsistent).

I do have several of the W4S ICEPower ASP-1000 based amps and are very pleased with them (MC7x500, ST-1000 and STI-1000).

I use them to drive Magnepans @ 84dB sensitivity which is a lot tougher load than your Klipsch.

What mode Klipsch do you have? I had the Chorus II's (101dB) and Academy for many years.

I also have other higher priced amps like Mark Levinson and Jeffrey Rowland. The W4S ASP-1000 based amps are very close performers to the Mark Levinson #336 costing 5X more.

HTH
Edited by emailtim - 6/19/12 at 10:44am

Thanks for the update. I have the Klipsch RF-7 mains, RC-7 center, RS-7 surrounds. I've read that these speakers love power (despite their high sensitivity) so I am planning on getting a very powerful amp for them. Currently running them off of an old (bought new) Harman Kardon AVR 8000/8500.

If anyone else can chime in for the Parasound Halo A51 and Sunfire TGA-7401 vs. the MC5x500 that would be great.

I have run all 3 kinda...

About 6 yrs ago I ran the PS Audio amp which is sorta like a first gen W4S since they were both built by Cullen Circuits on the Bang Olufsen Ice modules.

That said I preferred the Parasound Halo but primarily for 2 channel. The PSA/W4S was next then the Sunfire.

The Halo ran hot!

As far as HT they were all close. Check the impedance curve on the RF 7s. Typically ice amps don't like low impedance loads.

If I am not mistaken, the minimum load on a RF-7 is 2.8 ohms at certain frequencies. Since the minimum load on a MC5x500 is 2 ohms, should I be fine?

I quizzed W4S about usage with low impedance speakers like electrostatics. They said no problem and many do use them. Said as the impedance is constantly changing with frequency that it is no issue. I know several Martin Logan owners using ICE amps with no problems and that really like them.

Kain,

The 2.8 ohm at what frequency is the question. Probably rather low so it will depend on were you have the LFE crossover set.

It will also depend on the levels you listen to for current draw.

For most home use I think you will be fine.

I was wondering if anyone with a STP had a problems with speaker levels after running Audyssey. I'm getting a difference of 6,5-7.0 between left and right speakers. Left side higher. I pulled out the STP and did another correction and both sides were within .5. I have swapped amps, wires and still no changes with it in line. Even had it checked at W4s. Any help or suggestions would help.

Kim

Some Facts,

I have the STP in the system with the 5508. Also that the issue is when using the HT Bypass feature that I see the speaker setting differences after running Audyssey with the 5508.

Thanks, Kim

Nope, no such issue here.

Just curious - have you run Audyssey without the STP, then reinsert it and play some test tones or something to see if the actual sound is lower one speaker to the other?

I thought of that earlier. I'll give it a shot now and check out some test tones.

Thanks, Kim

I just put the STP in line with HT Bypass and check the levels in the 5508. The left speaker was a 65 on the meter and the right speaker at 72. All others are fine.

I have been trying to figure this out for the last 2 months after sending it in for repair and W4S can't produce the same issues.

What now!

Thanks, Kim

Well, I had to switch the amps around again just to be sure and had the same issue.

Sleep on it tonight.

Thanks. Kim

If Wyred's service people are competent, then the problem is on your end (they have a good rep I thought.)

Have you tried reversing the cables between STP and 5508 (left to right to eliminate a bad cable?)

Reversed the cables and no difference. I agree about Wyred's service. I really want it to be on my end, so I can eliminate the issue. Wyred tested it when they had it and said the HT Bypass was balanced. No issues.

I wanted to comment on the problem Kim is having with his STP. I have been to Kim's house a number of times to listen to music in his very nice HT/Audio room. A few months back we noticed the the speaker levels were not balanced when listening to the STP with a 2CH SACD. I was sitting dead center and the vocals of the disc we were listening to were not centered as they should be, they were way off. Kim broke out his SPL meter and sure enough the levels playing this specific disc were off 6-7dB. Of course we checked the balance setting of the STP first and it was dead center. After that we spent an hour reversing cables, amps and so on only to see the issue was with the STP.

Kim sent the STP to W4S and they found something wrong with it but I do not recall what it was. The other issue I noticed with the STP before it was sent to W4S was there were loud pops at times when the volume was changed. This was also corrected when it was serviced the first time I believe. Then Kim noticed the issue when running Audyssey and sent it to W4S again. W4S checked it out and sent it back to Kim stating there was no issue. Now Kim has it back and it is doing the same thing.

In my opinion there is something wrong with the HT Bypass feature on Kim's STP. If the STP is in Kim's system and the R front and L front speaker trim levels are set to 0 (with the 5508) the levels are off 6.5-7dB when a SPL meter is used. To get the SPL readings Kim is using the test tones from the 5508. In other words the R front speaker is 6.5-7dB higher than the L front speaker. If the STP is removed from the system and the speaker levels are checked (same settings with the 5508 unchanged) they are dead on with no difference using the SPL meter. So unless both Kim and I are missing something it has to be an issue with the STP. I would believe W4S's tech staff are very good as well but I wonder how they are checking the HT Bypass feature? I feel Kim has been very patient through out this issue much more than I would ever be.

Bill

That was my thought - I always imagine tech guys as poking and probing and reading meters. They need to just insert it into a working system.

Dealing with service people is a social engineering exercise ... you have to be confident that there really is a problem, and that you have identified it 100%, and it needs to get fixed, now.

Well after numerous challenges removing cables, exchanging AVRs everything is back to normal. I have no clue what the problem was but I am definitely convinced that the STP-se is working 100%.
I'll let it be and just listen to good tunes.

Thanks to everyone,
Kim

Ahh, life is good