Sunday, 22 May 2011

Arcam Alpha

The Arcam Alpha was the first CD players in Arcam's lower cost Alpha line.  This player is based on a Philips model, and uses a Philips mainboard, loader and laser mechanism, but uses a Arcam case, power supply and DAC board.  It shared the same style as contemporary Alpha components, namely the Alpha 1, 2 and 3 integrated amplifiers and the Alpha tuner.  It is not to be confused with the much more modern Alpha One, to which it bares no resemblance.


This player uses a familiar range of ICs; the TDA8808 and TDA8809 servo, the SAA7310 decoder, the SAA7210 digital filter and the TDA1541A DAC IC.  Arcam tapped the I2S line from where it would have entered the mainboard's original DAC IC (a TDA1543), and routes it to an Arcam designed and made DAC board.  This board contains the TDA1541A DAC, the two OP27 and two NE5334 single opamps that form the output stage and two LM317Ts and two LM337Ts that regulate the supplies needed for the DAC IC and output stage opamps.  The board also contains a rectifier bridge and filter capacitor bank.


The sound quality of the player in stock standard form is actually quite good.  The better power supply to the DAC and improved output stage put this CD player a step ahead of many others, such as the previously posted Mission PCM2.  However, as always there is room for improvement.


I've owned two examples of this player, one was an Arcam Alpha, one was an Arcam Alpha +.  There are only a few differences between the two models, specifically:

  • The + has Blackgate output capacitors, whereas the regular model uses general purpose types.
  • The + adds a pre-regulator to the DAC board supply.
  • The connector is keyed opposite on the + compare to the regular model, hence the pinout is reversed.

The particular example pictured, a plain Alpha, I bought in poor condition.  It could only read some CDs, and when playing the few it could play it would often skip.  In previous posts I've often said that electrolytic capacitors should be replaced in players over 20 years old for reliability, and for the Alpha this was the case.  Degraded electrolytic capacitors in the servo caused the player to perform so poorly, and all that was needed was their replacement.


I haven't yet extensively modified this player, it is a work in progress.  I have done the following things:

  • Replaced the electrolytic capacitors.  As I said above, this was both to make the player functional and to increase performance.  I used the same combination of Nippon Chemicon KMG, LXZ and PSA series capacitors as I normally do.  For the output coupling (also known as DC blocking) capacitors I used Nichicon ES capacitors.  These are reasonably priced, and are the best coupling capacitor to use where you have limited space.
  • Replaced the output stage opamps.  The OP27s and NE5534s were much better than what was used in the average CD player when the Alpha was made, but the state of the art has moved a long way since then.  I replaced them with LME49710s, but this is by no means the only opamps suitable.  This player uses only single opamps, which gives it better channel separation.
 This is another player that will benefit from a low noise clock.  I plan to install one once my newer, more compact clock design is ready.  I have now received the PCBs for it, but I am still waiting on a cople of components.

All up, this player is not too bad in stock form, but can be quite a good performer when upgraded adequately.  It definitely a good base for modifications and worth buying if you see one for sale in the second hand market.

38 comments:

  1. Would be good to contact you to discuss upgrading an Arcam 7se that must be some 12 +yrs ago. I would appreciate some of your guidance to upgrade diodes / capacitors & Op amps

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    1. Sure, post your email address on your Blogger profile page and I'll get in touch. The Arcam Alpha 7SE is a very different player from the original Alpha, so not all of what I suggested above will be relevant.

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    2. Dear Anton, I also have an Arcam Alpha 7se and I would love to know whihc op amps I need to change to make it sound better as I was once told that it would start 'singing' only with better op amps. Now I am a drummer and definitely not at all able to do any modifications. However, a friend with some soldering skills has offered to change op amps for me - and perhaps something else you suggest. Many thanks
      Carlo
      moschetta.carlo@gmail.com

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  2. Hi - do you know anyone Taupo north who might put a tube output stage into a cd player like e.g. a Marantz CD 5000. Thanks -Paul W

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    1. Hi Paul,

      No, I don't know of anyone who does that kind of thing. I designed a vacuum tube output stage and put it into a TDA1541A based player a couple of years back. It worked quite well, but no better than what can be achieved with a good solid state design. Given the need for a larger mains transformer, the high heat output and bulky size, I personally didn't think much of it. I ended up selling off the output stage and breaking up that player for parts.

      If you have more questions and want detailed advice, post you email (I won't publish the post with your email in it).

      Anton

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  3. can you possibly contact me at dashdespatch@yahoo.co.uk as regards a repair my alphas finally bit the dust am now using my ps3 which is good but not a patch on the arcam

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    1. I'll drop you an email.

      Thanks,
      Anton

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  4. Forgive me for disturbing you: I've bought a used TEAC PD200 cd player. It's working but the sound cracks on the right channel. What could be wrong in it? I could get a friend to do the necessary repair with your advice.

    I am in Bangkok and my email is: lowchoonyong@gmail.com

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    1. I'm not really familiar with TEAC players. Looking at the PD200, I think you might be better starting out with a higher quality CD player anyway.

      Thanks,
      Anton

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  5. Hi Anton,
    I own an Alpha Plus cd player bought new in 1993 with other separates: all still in regular use. I've been thinking about getting a more recent cd player, but coming across your blog and other sites which sing the praises of its DAC chip, I've changed my mind. There have been occasional random skipping problems, but not recently, and otherwise it works apparently fine. My question is: even if it seems still to sound great, will there in fact inevitably have been a deterioration of components e.g. capacitors, such that replacing them as you suggest can only make a sonic improvement?!
    Thank you in advance, for your advice, and the help you offer on your blog.
    Best regards,
    Alex Moore

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    1. Hi Alex,

      It's definitely not worth buying a new CD player now, they're obselete and there aren't many good ones still being made. If you want a new digital source, a DAC is the way to go.

      As for your Alpha+, while there will have been some degradation over time, its effect on sound quality won't have been massive. I still stand by what I did to my Alpha though, I wouldn't change what I did above.

      Thanks,
      Anton

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  6. Hi Anton,

    Thanks very much for your reply. I have a lot of CDs (and LPs) in good condition, and I like having the physical discs plus the notes and lyrics, etc. I do listen to mp3 music files (home-created at relatively low loss) on my phone via a Marshall Kilburn portable speaker, and that's fine for casual listening. I can see that FLAC files stored on a laptop linked by Bluetooth to a DAC on my hifi could be a good way forward for new albums that I want, I'll start doing the research. Meanwhile doing the upgrade to the Alpha Plus seems like a very good idea, do you have a components list already available?

    Thanks again,
    Alex

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    1. Not really, you're best to observe what's already fitted as a starting point. Have a look at my post on the CD150 for a more in-depth example.

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  7. Hi Anton,
    I read your piece with interest - thanks.
    I have a working Arcam Alpha Plus as a spare player. I would like to try the modifications you describe. I can solder but have very limited electronic knowledge. Do you have a walk-through and details about which parts need to be replaced and how to describe/order them. I would be very grateful for your advice and help in attempting this.
    Thanks and best wishes
    Martin

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    1. Hi Martin,

      Check out my blog post on the Philips CD150. For this player I went into detail on performing basic modifications to a CD player. What I've said there is fairly applicable to your player.

      Make sure you get some decent equipment (a good soldering station and desoldering pump are important), if you let me know what country you live in I might be able to provide more specific advise on tools and a parts source.

      Good luck,
      Anton

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  8. Hi Anton,
    Thanks for your reply.
    I will check out the CD150 page.
    I live in the UK. I have a coarse and a finer soldering iron. I bought a de-soldering pump from Maplins (Sells electronic parts etc) but it seems very crude and poor at "hoovering" up molten solder. It is spring loaded and snaps back suddenly which is not so good for fine/accurate work. But it is likely my low skill level!!
    Cheers,
    Martin

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  9. Hi Anton,

    Many thanks for your advice. I have looked at the CD150 post and have been learning about soldering desoldering through web videos.

    I live in the UK and would be grateful for pointers to which parts/relacements I should get for the Arcam Alpha Plus and possible parts sources where I can buy these.

    Cheers,
    Martin

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    1. No problem.

      I'd definitely look at getting a soldering station, from your description above it sounds like what you have are unregulated irons, which aren't really suitable. The boards you'll be working on are not through hole plated, so desoldering braid is quite a good option. Make sure it's a quality brand (Goot, Multicore, Chemtronics, Edsyn and others) and from a reliable source.

      As for where to buy the components, Farnell or RS are good. Farnell / element14 is my usual source. I had a look at what soldering stations they had as well. This one looks okay, basic, but it should do the job:

      http://uk.farnell.com/tenma/21-10115-uk/soldering-station-60w-220v-uk/dp/2064549

      It also uses Hakko 936 compatible tips, so replacements won't ever be a problem. Make sure you get an appropriate tip as well, I'd use a 1 to 1.6mm chisel tip.

      Anton

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  10. Hi Anton,

    I was searching for an Arcam Alpha Plus reviews and came across to this site. I'm keen to what you did with this player and want to do it as well. I just purchased one in Trade Me and want this to be my 2nd player aside from my Arcam DV89. You mentioned in your previous comment that you can help direct parts sourcing and some tools. I'm just new to soldering and some good advice will be very much appreciated and helpful.

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    1. Check out my post on the CD150, where I go into a bit more detail. The best advice for soldering is to get the proper tools - a soldering station, good brand solder, good brand desoldering braid and/or a good desoldering pump. The worst possible combination is crappy tools and beginner skills!

      It's definitely worth checking out some soldering tutorial videos, this is probably the best (even though it's an Aussie):

      https://www.youtube.com/watch?v=J5Sb21qbpEQ

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  11. Hi Anton, greetings from Nottingham, England.I came across your blog and hope you can help me. I have no expertise in this matter but would be grateful if you could tell me which laser is installed in my Arcam Alpha CD player. It is the original and not a plus ,one etc. It was working perfectly until today when I needed to remove it to gain access to my amp. Sadly I had left it powered up and heard a grating from the loading mechanism- there was a CD in it at the time and now it will load and try to read but the display comes up Error. I have taken the lid off to see if anything had dropped off but nothing was obvious and I ended my inspection at this point. Needless to say I'm pretty gutted but any advice as to what may be the cause will be gratefully received. I would be interested to know if any other laser mechanisms from non-Arcam players would be compatible as I am aware that sometimes they are multi brand versions. Thank you and best wishes, Craig.

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  12. Hi Anton, could you tell me if there are any compatible replacement lasers for my Arcam Alpha CD player, original not plus, one etc.I stupidly left it powered up whilst moving it and it had a CD in- yes stupid! It now will not read and comes up with the error message in the display. I have taken the cover off to see if there was anything obvious but there did not appear to be anything dropped off/broken so I replaced the cover as I have no expertise in these matters. I am grateful for any advice, the unit is UK. Many thanks, Craig, Nottingham, England.

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    1. I'm surprised moving it with a disc damaged the laser, but I suppose it's possible. The Arcam Alpha uses a Philips CDM4/19 laser mechanism, they're fairly common and used ones are readily available. Be aware that replacing a laser involves using proper anti-static precautions and carry out basic adjustments to the player's servo electronics after the swap.

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    2. Hi Anton, I thought I would let you know that it was indeed the laser that failed on the Arcam. The chap I bought it off did the repair for £35 for the unit and £15 labour and it now reads CD's much quicker and so far works faultlessly. Once again thank you for your help and the great site. Best wishes, Craig, Nottingham, England.

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    3. Great to hear, I'm glad it worked. I bet you won't move it while it's running again!

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  13. Hi Anton, I currently use an arcam alpha in a naim system but I also have a philips cd850mk2. In my opinion the arcam sounded better than the philips but I am wondering would I notice an improvement in the philips if I purchased a DAC? I am tempted to use the philips because of its transport. Thanks

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    1. Hi Anton,
      I am an Arcam system owner, bought new in UK , now back in my native southland. The poor old Alpha CD is slow to warm up, and I am getting ready to replace the caps. Do you by chance have a BOM of the parts required ? And recommend a supplier, I usually use RS . Thanks,
      shaneapopham@gmail.com.

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    2. I don't think you'd notice a difference between the two when used as digital sources. I'm not really keen on S/P DIF input DACs, there are better options now (anything not synchronous, such as USB Audio Class 2).

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    3. Shane - I don't have a BoM, I've done that kind of work on a player before but I don't keep records. Best thing to do is open the player up and record the values directly off the capacitors themselves.

      My usual suppliers would be RS, element14 or Digikey. RS and element14 have free shipping on even small orders, so they're good options.

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  14. Hi Anton. I just picked up a used Arcam Alpha Plus. It sounded fine when I tested it with the original owner, but once I got it home it started playing intermittent static about 29 mins into a CD. I'm thinking about recapping. Can you please list how many caps I'll need, their values, brand (Nichicon?), and any other recommendations?

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    1. That's not great.

      Intermittent static sounds like a problem in the analog stage, possibly with the DAC itself, but it's hard to say without hearing exactly what you mean myself.

      In simple terms, if there's static with music still audible, I'd think analog, but total replacement of the music with static would make me think it could be either an analog or digital issue.

      If it does sound like it's analog, I'd be checking the DAC's supplies and the DAC itself.

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  15. Hi Anton,

    Great to see this blog from you. Really happy that I can possibly upgrade this as per your blog. I just recently purchased one from TradeMe, yes from NZ :) and wanting to know where you bought the parts and list as well If you can provide one to me - droid_spyke@yahoo.com. Really appreciate it. TA

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    1. They're nice players, and I still see the odd one come up on TradeMe. I don't have a parts list, the best thing to do is open the player up and record the values directly off the capacitors themselves.

      Best supplier would be RS or element14 - big range with free shipping on even small orders.

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  16. Anton this is fantastic, love the idea of rejuvinating my old Alpha 8!

    I'm also curious - would it be possible to expose the DAC for connecting to an external digital source? The unit has a digi out, I'd like to add a digi in. Thanks for the breakdown! cpreager@hotmail.com

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    1. Yes, you could make the DAC portion of the CD player into a standalone DAC, but it isn't a trivial job. It's not something I'd recommend, but it could be done.

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  17. Hi Anton-Do you have a circuit diagram of the Arcam Alpha CD player?
    my house was last week hit by lightening which apart from damaging satellite receivers and TVs (PS's and HDMI circuits) also took out my Arcam Alpha CD player. When I power it on the CD spin motor starts for a short time, the green power on panel light -lights up but the CD platter doesn't slide out when pressing the OPEN button. The CD player was switched OFF at the time of the lightening strike so unless it jumped the switch (unlikely? fuse and transformers seem undamaged) it must have entered through the Audio Output shields, which were directly connected at the Amp (which was undamaged!) to the satellite receiver(now dead) audio output shields and to the internet modem(also totally dead)
    Of course It could just be a strange coincidence that the CD player broke the same day as the lightening strike but I thought I would start by checking the power supplies
    PS I liked your articles-you are an enthusiast, cheers Bernard

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    1. I do have a service manual, but it's probably easier to download it directly. Just do a web search, it's hosted for free.

      I'm not sure where I'd start looking for lightning damage. Does the display show anything?

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