Thanks, all! Before I read your helpful suggestions, I decided to live on the edge and try the dip switch settings on the M5-HP cover (as opposed to the Vandy web site). Using the 20k ohm setting, my bass has been restored to levels very similar to what I had prior to the amp upgrade. Now, shortly before the amp upgrade, I installed new cables between my DAC and pre. While they were overall a big improvement, the bass levels seem a bit reduced. So, follow-up question: If I want to goose the bass a little bit, am I better off monkeying around with the 10k ohm settings on the M5-HP or just dialing back the efficiency knob on the 2Wqs a bit? I would hate to fool around with the Q setting - I love the tight bass I get with the current settings.
@audioconnection Johnny - when you say to connect the voltmeter to the "amp's" speaker posts, are you referring to the main amplifier or the plate amps on the 2Wqs? Thanks! |
@hifiman5 - Yup, I know, I live La Vida Loca. But the Vandy web site does specifically say "when using the M5-HP with 2W series subwoofers, the sticker on the chassis should be ignored. Set the switches according to the applicable chart below." Unless what is meant is the V2W, I don't understand this. Why would "2W series" exclude the 2Wq? |
@mr_m@hifiman5 Ah, that makes sense. The 5 series speakers cross over at 100Hz. So, I guess for now, I am living in sin. |
@mr_m - Yup, I’ve heard. But every time I’ve interacted with him, both by phone and in person (about half a dozen times), he has been nothing but pleasant and patient.
I left the screws off the chassis of the M5-HPs, so when I have the time, I will play around with the 10k setting for 80Hz. |
@audioconnection I am starting to lose it. Tried 80Hz settings recommended, 1 up and 1 down, and I get no sound out of 2Wqs. Upped efficiency control to 85 dB, no difference. Burned a CD of Vandertones, but my amp did NOT like being touched by multimeter pins.... triggered protection circuit repeatedly.
I set the M5-HPs back to the 20k settings and will try letting them and the amp burn in for a while.
FYI, I took the M5=HPs and 2Wqs out of the chain altogether and got much better low end from my speakers run full range. I really miss what the 2Wqs used to do. :-/
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@hifiman5 - it is possible, but what a coincidence that they both seemed fine when I pulled the main amp for the upgrade, and are both dead three months later upon the amp's return. Also, even though I got better bass out the mains run full range, the level of bass was still way down from what AI have heard these speakers do when run full range in the past, before the amp upgrade.
But if all else fails, and after the amp has run in some more, I will have to try new batteries. But with the soldering, that's a real PITA. |
@audioconnection - I started with the preamp volume set to zero, and the protection circuit still engaged, before I had a chance to increase the volume. I am one of those few who RTFM.
I began to think that there was something wrong with the M5-HPs, and they would have to go in for service (lithium batteries installed in 2012, so probably not two dead batteries at the same time). I retained the in-line 10K filters I had used prior to acquiring the M5-HPs for such a situation. I put them in and got more bass out of the 2Wqs than with the M5-HPs set to 10K. That is puzzling.
I raised the bass level on my preamp (those rarely used tone controls do come in handy!), and got sufficient, if not ideal in quality, bass output. I was able to determine that the 2Wqs are indeed working and generating sound. I got similar results with multiple source components.
What this means is that, I think, the new amp is not putting out much bass. Hopefully this is a burn-in issue, but I will confirm with the amp’s builder today. Of course, this does not explain why the in-line filters offered so much more bass output than the M5-HPs set to 10k.
If I am wrong about the amp, I will give you a call, Johnny. Thanks for all the assistance. Ditto everyone else here. |
@mr_m - Oops, I think you are correct. Brain fade, there. I will dial the level control back up tonight. Could be at least a contributing factor. |
@audioconnection - Well, the amp was modded by the original manufacturer, so I will have a conversation with him about the input stage. Once I have this conversation with the manufacturer, I will re-evaluate and look into battery replacement. Thanks! |
@gdnrbob - In 2012 I had Lithium batteries installed. Date in Sharpie for replacement is 2022. Batteries have expiration date of 2020, so I was hoping they would last past 2018.
@mr_m - I am sure of nothing. This would be the first time I replace batteries since I bought the M5-HPs. @tomic601 - (Atomic! I get it!) I tend to agree with you. Here is a sequence of changes in my system:
I was really digging the sound of my system, including the 2Wqs, when I upgraded cables connecting my DAC to my pre. This was in June of 2017, IIRC. The cables were a definite improvement, although I did notice a slight reduction in overal bass output. I chalked it up to cable differences and resolved to increase the output of 2Wqs as soon as I had some time (the controls are not that accessible, and I mass load the 2Wqs, so it is a bit of a project to move everything around). Before I had gotten to adjusting the levels of the 2Wqs, my amp croaked on me. After speaking with the designer/builder of the amp, I decided to send it in for repairs and upgrades. The upgrades included almost all new interior parts (circuit board, transformer, wiring, etc.). This took three months (don't ask), so for three months, the 2Wqs and M5-HPs sat unpowered and disconnected.
When the amp finally came back last week, I connected everything, and adjusted the M5-HPs to 20k (single ended) to reflect the change in input impedance of the upgraded amp from 10k to 22k (Johnny's concerns notwithstanding, I doubt my amp builder would get the input impedance wrong; he is a bit of a wiz at these things). While the upgraded amp has much to offer over the amp as it was before, the bass is just MIA. I know some additional burn-in time might be needed, but this is extreme absence of bass below ~150Hz. If I max out the bass control on my preamp, I get an acceptable level of bass, but it lacks punch and extension. Doing that did, at least, allow me to determine that the 2Wqs are functioning, as I could feel very slight cab vibrations.
OTOH, since the old in-line filters and my speakers run full range have marginally better bass (but still nowhere near acceptable), I do suspect the M5-HPs as well.
I am scheduled for a call with the amp builder tonight, who suggests that the amp may not be properly biased for my system. Not sure how this could affect the bass output. Once I have the amp squeared away, I will focus on the M5-HP battery replacements. |
Ok - Progress!
Last night I spoke to Richard V. It was very worthwhile, as he explained a number of things to me about the M5-HPs. In particular, he told me that a dead battery will not result in diminished bass output, and that the the problem did indeed seem to be the amp and the input resistance. It was a great call, and took place before I spoke to the amp's builder. Richard felt, as I did, that it was just too coincidental that both the M5-HPs would have their batteries die or fail at the very same time, and at the same time I put the amp back in the system.
Prior to my call with the amp's builder, I snapped a few pics of the inside of the amp and sent them to him. Well, that was the problem: The amp was knocked around a bit by UPS, and stuff had come loose (I had very little idea what I was looking at, but the pics showed everything). Specifically, the transistor bridge was no longer connected to the heat sinks. These of course overheated, and caused a chain-reaction of other issues. So, the amp is going back to have the damage repaired and everything reattached properly.
So, there is light at the end of the tunnel. Diagnosis is 90% of the battle. Now, who do I speak to at UPS to get compensated? ;-) |
@gdnrbob - It won't cost me anything. The amp's builder is covering shipping and the repairs. He is a stand up guy. If I had to pay for the shipping and additional repairs, you might have a point, although, based on what I heard with the broken amp, I have pretty high expectations for the repaired one. The only thing I might pay for is to have it double boxed this time. |
@tomic601 - Turns out, RV was on vacation the week everything went wrong. I had called Vandersteen Audio and got accurate answers to the questions I asked, but it wasn't the same as getting the complete story from The Man Himself. |
@gdnrbob - (why doesn't your handle ever show up when I type @?) The box was intact, but could have been tossed about a bit without destroying the box, and there is no strapping or heavy corner guards. That's why I offered to pay the difference for double boxing. The amp is en route. I will report back when it is returned to me. If all goes well, I think a full review of the upgrade is in order. |
BOOyah! Progress! After many months of head-scratching and curse-muttering, I can finally see (hear?) some light at the end of the tunnel.
Last night, John Rutan of Audio Connection stopped by, and he worked methodically through my lack of bass issue. In the end, it looks like it might actually be the M5-HP crossovers themselves. He installed the X-2 temporary crossover and, using the 33K jumper setting, my bass was back! All of it! So, as per John, the next step is to send off my M5-HPs to Hanford for a thorough checkup. Perhaps, John suggested, the caps in the M5-HPs have failed. Since I purchased these M5-HPs used in 2012, I have no idea how old they actually are. There also is some confusion over the jumper settings for the M5-HPs when used with the 2W series subs, as the settings were apparently revised, most likely after my M5-HPs were produced. So, we shall see. I hope to ship the M5-HPs out tomorrow. But at least I got the system up and running again with the X-2 John was kind enough to lend me. |
After speaking with Ray at Vandersteen and John Rutan, my impression is that there have been only minor running changes to the M5-HP over the years. Mostly things like wire connections and dressing, and I think there may have been a revision of the recommended dip-switch settings when using the M5-HPs with the 2W series subwoofers. Other than that, I can't say. |
Sorry I never posted the outcome here. I thought I had. Anyway, the issue was that my M5-HPs, which I bought used, were custom units with 10 rather than 8 dip switches (I should change my rating on the Audiogon seller, who never mentioned this to me). Using the sticker on the case of the crossover was indeed the correct way to use these with my 2Wqs.
That's the good news. For about a year, I was really enjoying the system. Then, earlier this month, catastrophic failure. The amp died on me, complete with sparking flashes and un-welcomed smells. As I decided after the last repair/upgrade, I am done with this amp (and it's builder). I need something I can actually lift on my own. It weighs 64 lbs., I need something under 40 lbs. And good sound would be nice, too.
The big problem is that I am not working, and my budget is really limited.
Many owners of Ohm speakers, like me, report excellent results using high powered class D amps. I know someone who builds these amps, and he has offered me a powerful stereo class D amp for a reasonable price. I have actually heard the monoblock version of the same amp in my system and liked it very much. I know a few owners of these amps and the general impression is excellent.
The problem is compatibility with the M5-HP. I spoke to RV, and he was emphatic that class D amps would be a bad match for the M5-HPs. Something about the actual input impedance being different than the published spec. He advised avoiding class D, but said if I went that way, to check the impedance myself with the meter and Vandertones. Note that when I had the monoblock version in my system few years back, I do not recall any issues with the M5-HPs set at the spec'd input impedance of those amps.
So, I guess what I'd like to know is, do any of you use the M5-HPs with a class D amp, or know someone who does? How has that worked out? I am in a real bind here, so I'd appreciate your thoughts. I am hesitant to buy used, and most amps I can afford, even used, are too heavy for me. Thanks!
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@mr_m - Thanks, that was helpful. Since my pre is tubed, our systems have a bit in common. I think I am going ahead with the amp. Hopefully, it will all work together. |
So, I am breaking in a Class D amp. I have no issues whatsoever with the amp and the M5-HP crossovers. The amp is spec’d at 10K ohms input impedance, and I have set the M5-HPs to 5K ohms, with excellent results. The amp itself is going through some changes as it breaks in, but I am optimistic, as I once had the mono block version of this stereo amp in my system for a few weeks and enjoyed it. I will say, though, that it and my class A/B SS amp sound very different from one another. Each has/had its strengths and weaknesses. With my limited budget, I have to accept that there will be some compromises. But overall, I am happy with it. And I can carry it under one arm!!!! |
