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    eye opening experince with sp 14


    mike drinkwater

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    Join date : 2012-01-27

    eye opening experince with sp 14

    Post by mike drinkwater on Sun Sep 23, 2012 3:08 pm

    About 6 months ago i purchased a sp 14. From the moment I received it it had a bad volume control. Roy was not too helpful which peeved me off no end considering the price. He almost made it seem like it was my fault. The best he could do was send me a few photos and suggest I buy a goldpoint control. He then had the nerve to tell me about 20% of his volume controls were defective. Great! Anyway i purchased a gold point passive pre amp for 300 dollars and was shocked to find out how much superior the sound is. The highs are much more defined. Channel separation is much better and the transients are amazing. The bottom line is there is a lot of snake oil on the internet and buyer beware. I'm running my goldpoint into a 15 watts per side mcalister tube amp and it sounds amazing. On a positive note, I sold my sp 14 for 500 dollars and disclosed the fact the volume control was defective.

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    Re: eye opening experince with sp 14

    Post by WntrMute2 on Tue Sep 25, 2012 6:15 am

    That's too bad. Roy has always seemed to stand by his products. No one wins when customer service is poor.

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    Re: eye opening experince with sp 14

    Post by PeterCapo on Tue Sep 25, 2012 1:57 pm

    Sorry to hear about that.

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    Re: eye opening experince with sp 14

    Post by tubes4hifi on Tue Sep 25, 2012 3:12 pm

    I would have purchased your SP14 for $1000 and simply replaced the volume control if it was bad.
    Interesting that I asked you 8 months ago if you wanted to replace it if resoldering the connections didn't fix it,
    but I never heard from you at all until a week ago.
    I asked you twice how much you wanted to sell it for and you ignored my emails, so I can't help someone that doesn't want help!

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    Re: eye opening experince with sp 14

    Post by mantha3 on Tue Sep 25, 2012 5:30 pm

    I remember a year ago reading threads of individuals who has hum issues building the then premier preamp. This was the same amp sold today only non Octal...

    These threads went on for months and I didn't see much help provided. 12 pages of threads with two different people who spent countless hours dealing with hum. I even chimed in with "How is it going? I was thinking of buying one of these preamps and checking in" One person got thru the Fall Winter and then put it in the attic... I never did hear that person come back around. The other sold his on this forum. I went another direction. I remember "Hum seems at an acceptable level.

    I went another direction too.


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    Re: eye opening experince with sp 14

    Post by turbotoy on Tue Sep 25, 2012 7:57 pm

    Sorry to hear about your experience.

    That said, I feel I need to offer my story, which was very different in some ways. I built Roy's SP12/PH12 almost a year ago. I made several amateur mistakes along the way, and in the end learned a heck of a lot about how the circuits function. I battled some issues that were totally my doing, and it felt great when I finally got the amp up and running to its full potential. Along the way Roy responded to my many emails, and usually did so within two hours; probably some of the best service I've ever gotten.

    There is one big "however" here... I too had/have the cheap volume attenuator, and it was scratchy right from the start. Roy suggested touching up all the solder joints, and that may have helped some. If the control is cycled full rotation back and forth about 20 times it will be quiet for a while, and then get noisy again within a few days. That leads me to believe the wipers/contacts are made of poor material that is oxidizing.

    So, my personal opinion (based on only my one experience) is that the cheap volume and balance attenuators aren't even close to the same quality as the rest of the components in Roy's preamps and don't belong anywhere near them. My next purchase will be a Goldpoint attenuator and I'll bypass the balance controls as I haven't found them necessary for my application. The balance attenuators also feel horrible. In contrast, the cheap input selector switch operates absolutely flawlessly and feels great.

    As far as sound goes, I've compared passive to the SP12 and you won't pry the SP12 out of my system at the moment (and I realize that is highly subjective).

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    Re: eye opening experince with sp 14

    Post by baddog1946 on Wed Sep 26, 2012 9:30 am

    Seems like every electronic device is born first as an idea then becomes a work in progress and finally achieves the regard it deserves. Even Einstein modified his theories.
    Look at the ST-120, the M125's and not the least the wonderful circuit in its many forms Roy came up with over 23 years ago we still all use today. from the day they were introduced all have undergone a lot of changes and improvements.

    Given the fact that VTA products are some of the best quality for the price products on the market I think that the SP14 is a good example of the work in progress theory and the fact it can be tweaked with good results lends itself to our hobby very well. Are we not the DIY guys??

    As far as communication goes it too is always a work in progress. I found Roy and Bob to be both helpful and willing to listen during all my projects and I think you will find that they realize good service is a vital part of the way they earn their living. Too bad things got out of hand in that department. Shit happens! I hope both sides of the equation can reach an understanding.

    I also welcome the critical balance that both negative and positive feedback can contribute to this forum. Censorship is a loser every time. Even if we don't agree we are obliged to protect right to be heard from the opposing opinions point of view.

    In the end forum members pointed out a simple solution that a better pot works fine and we will probably see it in the kits in the near future. Thinking in terms of solutions is always more productive and educational. Have a good day


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    Re: eye opening experince with sp 14

    Post by RockyAM on Wed Sep 26, 2012 9:44 am

    I was sorry to hear that the original poster had problems with his preamp. It appears that from Tubes4hifi's (Roy's) post that he offered to replace the defective pot months ago yet never heard back from you. Personally I have dealt with both Roy and Bob and have had nothing but excellent service from both. Emails are quickly answered and the information offered is right on the mark. RockyAM


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    Re: eye opening experince with sp 14

    Post by GP49 on Wed Sep 26, 2012 10:35 am

    I just couldn't help noticing that only one day before the original post on this forum complaining about a poor quality part and a rude supplier, a message on another Dynaco discussion forum was posted...with, if anything, an even more personal attack on a supplier of Dynaco aftermarket parts and circuitry for poor quality and rudeness.

    The message was posted as a REPLY to a previously-existing thread but has nothing to do with that thread. Its author says he can't identify himself ("I cannot sign my name to this warning"). The linked E-mail address may be a fake, anyway (they are PUBLIC on that board, unlike here).

    It gives one pause...what's REALLY going on here? Is it a coincidence that both posts, separated by only a day, involve preamps? Or did one inspire the other, one or both totally legitimate?

    In case that message on the other discussion board disappears...and it HAS been reported to their moderator as potentially libelous (UPDATE: it was removed by the moderator as "flame bait" about an hour after this message was posted here) it is:

    > Posted by DELETED on September 22, 2012 at 05:00:29
    > In Reply to: DELETED Audio Website Down, posted by DELETED on
    > July 25, 2012 at 12:56:50:
    > Mr. DELETED is a true believer in his talents and skills. I am sure
    > he imagines himself honest and earnest. However, he lacks the basic
    > Electronic Engineering background and knowledge required to design
    > and produce the modifications and improvements his products promise.
    > Many of his products either will not perform as advertised or,
    > worse, can be DANGEROUS.
    > E.g. his PAS power supply board employs a second transformer for the
    > heater voltage. This part is seriously under-rated for Amperage,
    > will over heat the PCB and chassis, and is a significant fire
    > hazard. Worse, there is a power resistor that is even more seriously
    > under-rated for the current demands of the circuit. It's
    > over-heating is far more dangerous and WILL eventually cause fire
    > without the fuse blowing. The heat sinks on his voltage regulation
    > chips are also grossly under-rated for heat dissipation. These chips
    > will eventually over-heat and either fail electrically or cause fire
    > and/or heat damage to your preamp. This board will run for weeks,
    > months or even a year prior to catastrophic failure. As normal dust
    > collects, the board's danger increases. Never mind that, as a DYIer,
    > you may touch one of the over-heated parts and suffer a severe burn.
    > This is one of his major products and it is clearly a FIRE HAZARD.
    > This board could never pass basic U.L. certification (Underwriters
    > Laboratory). To prove me wrong is easy. Mr. DELETED should simply
    > submit his products for U.L. certification.
    > Not only is this board dangerous, but it will cause much noise and
    > 60 cycle hum in your preamp, -exactly one of the main issues issue
    > it promises to cure. Mr. DELETED has failed to take into account the
    > complex EMF fields that occur when two power transformers are
    > introduced into a single chassis at close quarters. Some problems
    > were simply due to the main board being jury rigged because Mr.
    > DELETED obviously had run short of the necessary parts!
    > This is just an example of a single product. Mr. DELETED has basic
    > circuit knowledge; however, he seems to have neglected essential
    > areas of knowledge. I admittedly have not reviewed all of Mr.
    > DELETED products. I suspect that some of his products are fairly
    > harmless, and may even deliver their promised performance. But of the
    > two major products that I reviewed, it was clear that Mr. DELETED
    > work and designs are neither reliable nor safe.
    > I must remind you that this is not a young inexperienced person who
    > is involved in the honest pursuit of learning and improvement, but a
    > person with many years of experience who has failed to comprehend
    > basic, but significant scientific principles.
    > I would not have bothered to write this warning if Mr. DELETED
    > products were not potentially dangerous far beyond what is
    > acceptable with ordinary DYI products. Tube DYI products always carry
    > a warning about high voltage. This risk is normal and acceptable to
    > most hobbyists. However, Mr. DELETED has repeatedly miscalculated
    > basic current and voltage requirements for simple but potentially
    > lethal circuits. His designs and products are the work of a person
    > who understands many valid electronic concepts, yet has mysteriously
    > failed to apply the minimal standards of a well-rounded, trained
    > professional.
    > The last thing a Dynaco PAS owner wants is to spend several hundred
    > dollars and valuable time for added hum, distortion, burns, and
    > potentially worse. If you are inclined to discount my warning,
    > please, at least, proceed with EXTREME CAUTION. At best, you will
    > learn about ground loops, EMF fields and over-taxed components. Be
    > safe.
    > I regret that I cannot sign my name to this warning. Mr. DELETED
    > hostile behavior and vitriolic language frightened this writer. His
    > response to what was simply a customer having problems with one of
    > his products far exceeded the bounds of acceptable adult behavior.
    > Therefore, if you have already purchased a product from Mr. DELETED
    > and are experiencing problems I do not recommend that you engage Mr.
    > DELETED in discussion. The products are not expensive. I recommend
    > that you simply write off the loss and be glad that your experience
    > was not worse.
    > If my writing causes Mr. DELETED to mend his ways, I will applaud his
    > decency and honesty.

    And then the ANONYMOUS author proceeds to insert a link to a LEGITIMATE parts vendor who probably is totally unaware of these happenings:

    > (Open in New Window)

    Last edited by GP49 on Wed Sep 26, 2012 12:52 pm; edited 4 times in total

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    Mean Spirited Post

    Post by DynakitParts on Wed Sep 26, 2012 11:40 am

    I like this part the best:

    "Hostile behavior & vitriolic language frightened this writer"

    Quite an emotional writer...

    Kevin @ Dynakitparts


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    Re: eye opening experince with sp 14

    Post by GP49 on Wed Sep 26, 2012 12:02 pm

    On checking, I'd say the post here is legitimate. "Mike Drinkwater" has only two posts on this forum. The prior one is from February 5, 2012 and DOES mention a glitch with the volume control; it also says he runs a "mcalister" amplifier.

    It reads:

    > sp 14 pre amp - Sun Feb 05, 2012 12:59 pm
    > I have spent the weekend listening to Roy's sp 14 that I recently had
    > built. All I can say is it is an unbelievable improvement over my
    > grounded grid pre . It is like having a whole new system. By far the
    > best upgrade I have made so far. Biggest improvement is the presence
    > of the instruments defined in space and the quality of voices is
    > pretty incredible. Peaks are much smoother and transients much better
    > defined. All in all fantastic piece of equipment. In spite of my
    > praise I have to be honest and say the initial few hours were rough
    > due to a intermittent glitch in the volume control. Roy was very
    > helpful and responded to all my emails. It also did not sound great
    > out of the box but has improved all weekend. I would imagine it will
    > continue to improve over the next week. The last thing I will say is
    > the sp 14 is very resolving. I had no idea listening to Oscar
    > Peterson how much he was humming in the background as it was not
    > being picked up by the old pre. I'm using the pre amp with a
    > mcalister amp, mk 3 frugal horns and eastern electric plus dac. At
    > this point I think I'm finally satisfied. Great jon Roy.


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    Re: eye opening experince with sp 14

    Post by mantha3 on Wed Sep 26, 2012 1:29 pm

    I purchased the TRIPLE speaker posts $35 pair when I built my ST120 2 years ago... The posts barely fit thru the rectangle opening on the back of the chasis and were not on the black plastic board in a straight line... Soooo, the metal of the speaker posts were touching the chasis and would have shorted out my amp given the chasis is ground. I would have had to pay to box and mail these back... As requested.. So I just ate my 35 plus shipping and have these in a box in my basement doing nothing. Any buyers?

    Point blank - Someone just paid that much for this preamp? Pull out another attenuator/Pot and TEST it.. Send it to the guy same day.

    People spend months with humming preamps and we see little posts on how to fix? Bad! Eye opening it was for me.

    Bob rules and I had a ton of support from him with the amp I built from him. Sorry, not seeing that on the other end of Tubes4hifi

    I'll pull the posts from this site if people think I'm making this up.

    One guy doing the preamp build finally gave up after months of build problems (hum) and as Spring arrived he wanted to move on the classic car given the better weather.. Another threw in the towel and sold his humming preamp on this site under the "FOR SALE". I saw both people post these final steps and even then I didn't see any support. I dont' think I've seen either person on this forum since and it certainly swayed me from any preamp purchase.

    These forums are excellent for information. For better or worse.


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    Re: eye opening experince with sp 14

    Post by djg on Thu Sep 27, 2012 6:39 am

    I built a lowly SP8 with no upgrades a while back. This project was pretty much at the limits of my electronics skills. I had one wire soldered to the wrong PC board terminal, which killed one channel. I sent the thing back to Roy. He fixed it, tweaked some ground issues and sent it back. 50 dollars. I wonder why the OP didn't do the same.


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    Re: eye opening experince with sp 14

    Post by grobinso on Fri Sep 28, 2012 5:03 pm

    Hi Folks. This is my first post, but since I'm the buyer of the OP's Sp-14, it seemed relevant to chime in (smile) Anyhow my intention is to actually drop it directly to my technician to have a look see, any cleanups etc. Replacing the attenuator may be in order but we shall see....



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    Re: eye opening experince with sp 14

    Post by Tom on Wed Oct 03, 2012 8:24 am

    First off, props for the civil tone and the fact that this thread wasn't deleted outright.
    Show a lot of class on this site.

    I am also the builder of a Lowly SP-8 (capitalized to give it the respect it deserves!),
    which had a bad hum when I built it. Roy diagnosed the problem as a missing trace on a new batch of boards and sent me the info on jumpering the ground. Fixed.

    Great service.
    Great product.


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    Re: eye opening experince with sp 14

    Post by tubes4hifi on Wed Oct 03, 2012 10:42 pm

    It's real old news by now, but wow, Mike's comments from Feb 5th sure sound like he was really happy and loved the preamp.
    I can't figure out why he waited 7 months to complain about a problem with the volume control that will be an easy fix,
    and the new owner who got it for under half price is gonna be really happy with it!
    Well, there's always gonna be 2 or 3 people out of a hundred that find something to complain about.
    I'm happy to help people who need it and don't give me an attitude like my whole intention was to rip them off.
    I didn't get here selling crap to people for over 25 years, I got here selling great value and helping people experience great sound
    and great value and most of the time great service. I'm just another guy who likes to spread the gospel of tube magic.
    No one is perfect 100% of the time, and no product is perfect 100% of the time. Let's hope this is the end of this topic . . .
    . . . may your tubes rest in peace . . .

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