[mythtv-users] so how does Tivo do it?

Thu Aug 7 11:14:19 EDT 2003

This is probably a dead topic by now, but here are the details on the S1 and 
S2 tivos...

S1 - http://www.9thtee.com/insidetivo.htm
S2 - http://www.9thtee.com/insideseries2tivo.htm

Cheers,
Achint

On August 5, 2003 19:20, Max wrote:
> To put this matter to rest, let me just point out that my comments were
> based on personal experience as an owner of at least 8 tivos over past 3
> years, both S1 and S2, both standalone and DirecTV and  it is not based on
> weight or looks or guesses - just plain simple experience.
>
> After hacking tivos for over 3 years you pick up on a thing or two.  So
> trust me, S2 boxes although faster, are not as good quality as S1. Does not
> mean they are junk, but the difference is there.
>
> And by the way on being able to hook up 137GB of drive space (un-hacked
> tivo kernel limit) vs 272GB - 272GB wins every time. (even if 137 is
> sufficient).
>
> As for your trading in your tivo for the TW Digital Cable recording device,
> I cannot talk about the TW box, I never seen it, but if it records digital
> directly like DTiVo, it will be a "night and day" quality improvement.
> After I got my first DTivo, I could not watch the standalone unit anymore
> unless it is set to BEST quality, and even then it was not as good. This is
> also the reason MythTV box will not replace my DTivo until it can record
> the digital stream directly (I am not holding my breath) although PVR250
> recording quality @4GB/hr from a digital source is pretty impressive.
>
> One thing I would watch out for in the digital cable box - if it is
> anything like when I had digital cable, many local and basic channels were
> still analog, thus it will still need to encode them, which mean quality is
> probably not going to improve much. Again, I do not know much about what TW
> is doing, maybe they are all digital now
>
>
> -M
>
> ----- Original Message -----
> From: "Jeff Williams" <JeffW at rockstargames.com>
> To: "Discussion about mythtv" <mythtv-users at mythtv.org>
> Sent: Tuesday, August 05, 2003 3:23 PM
> Subject: RE: [mythtv-users] so how does Tivo do it?
>
> > Well part of your claim that S2 quality was lower than S1 was the fact
>
> that fewer hard drives were supported, the case wasn't as sturdy and
> components had been removed from the motherboard (see below).  My point is
> fewer components, all else being equal, means greater reliability, not
> less. No, I'm not vouching for the quality of the capacitors (though that's
> getting a bit specific - these are 1 cent or less parts in quantity and I
> would highly doubt that's where they're trying to save money), and I never
> said S2 models were definitely better or even the same as S1 models.  But I
> am saying one less hard drive and a more tightly integrated motherboard
> should, by themselves, increase reliability.  You don't really know
> anything about anything else in the machine, so there's no real conclusion
> that can be drawn.
>
> > As for the power supply (which you mention in relation to the dual hard
>
> drive support), there's no reason for a power supply to support more
> hardware than what is required.  If I buy a 400 watt PSU for my PC and my
> PC only ever draws 130 watts, that extra capacity isn't doing anything for
> me but burning a hole in my pocket.  A 400 watt power supply that's
> actually supplying 130 watts isn't necessarily going to be any better
> quality than a 150 watt power supply that's supplying 130 watts.  (To keep
> somewhat on-topic, this is applicable to Myth PC's too - I know there have
> been power supply questions around here before.)  There are other things
> that go into making a good power supply; ripple, consistent voltage,
> efficiency, etc.  I don't know that having a wattage rating lower than the
> series 1 TiVo models is indicative of anything but the components requiring
> less power.  It's about like saying a car with a top speed of 200 is
> "better" than a car with a top speed of 125.  It !
>
> >  may or may not be; you don't know anything about the quality of either
>
> car just from that one number, all you know is one is potentially faster if
> you demand it to be.  But they'll both go 65mph equally well, and the
> slower car may even be quicker off the line and may break down less too.
>
> > So series 2 models could be either better or worse, we don't know, and I
>
> don't think it's possible to make a definite assertion one way or another
> as you did.  I am sure series 2 models do cost less to make than series 1
> models, in the same way my 52X CDRW drive no doubt cost less to make (and
> buy) a month ago than my 4X CDRW did that I bought 3 years ago.  That's
> just the way technology is; there's no way anything in a TiVo costs any
> significant amount of money now even if they are using top-quality stuff.
> Costing less, using fewer parts and being less reliable are not all the
> same thing.
>
> > Again I'm sure I sound like I'm defending my TiVo, but really I'm just
>
> trying to point out the fallacy of a generalization... it's the kind of
> thing I see a lot in relation to a lot of different hardware, not just
> TiVo. I mean, some people measure the quality of a piece of hardware by how
> heavy it is, not even realizing that a lot of hardware makers put lead
> weights in their products specifically because they know people do this! 
> (Your mouse probably has one - open it up and see.)
>
> > > -----Original Message-----
> > > From: Scott Blomfield [mailto:ScottB at Cavps.com]
> > > Sent: Tuesday, August 05, 2003 5:12 PM
> > > To: Discussion about mythtv
> > > Subject: RE: [mythtv-users] so how does Tivo do it?
> > >
> > >
> > > You can get better or lesser quality components of pretty much any
> > > electrical component.
> > >
> > > Where you see "three pieces" one of which is a PCB, someone else sees
> > > hundreds of different transistors, capacitors, etc etc.
> > >
> > > I have not seen you vouch that the quality of the capacitors
> > > is the same
> > > as in the series one tivo. They may be of the same "quality"
> > > but with a
> > > lesser lifetime. Or the whole thing might just plain be
> > > better quality.
> > > Who knows.
> > >
> > > I just wanted to point out that what you consider parts and what other
> > > people consider parts can and probably are two different things.
> > >
> > > -----Original Message-----
> > > From: Jeff Williams [mailto:JeffW at rockstargames.com]
> > > Sent: Tuesday, August 05, 2003 3:59 PM
> > > To: Discussion about mythtv
> > > Subject: RE: [mythtv-users] so how does Tivo do it?
> > >
> > > Well I think my main point was that a lot of people take reducing size
> > > and weight to mean a reduction in quality, when just as often the
> > > opposite is the case.  Having one large hard drive vs. two
> > > smaller ones,
> > > for example, actually *increases* reliability.  As does integrating
> > > everything onto the motherboard.  Fewer parts means fewer parts to
> > > potentially fail.
> > >
> > > I haven't played around with a series 1 box but as far as physical
> > > construction goes, I just didn't see anything in my series 2
> > > that could
> > > really be any better built than it is.  I mean what are you
> > > going to do,
> > > make the motherboard thicker?  Use more screws?  The physical
> > > case could
> > > be made differently, maybe, but it's built pretty much like
> > > every other
> > > home theater component.
> > >
> > > The quality of the TV encoder/decoder and DAC, you could be right for
> > > all I know.  I do notice a slight degradation in my signal even at
> > > highest quality.  But it's very slight, and in reading the
> > > tivocommunity.com forums it seems like some people see it, some people
> > > don't, and it doesn't really matter if you have a series 1 or 2.  More
> > > people obviously have series 2 at this point so probably more people
> > > notice the degradation with these machines.  But I can't say for sure.
> > >
> > > Not that I'm really a TiVo defender.  I'm actually planning
> > > on replacing
> > > mine; I had originally planned on replacing it with my Myth box but as
> > > I'm having some remote control issues I'll probably just
> > > replace it with
> > > the new Time Warner PVR's that are coming out and use my Myth box for
> > > things other than watching live TV (archiving TV shows,
> > > watching DVD's,
> > > playing MAME games, etc.).  And one of the reasons I'm replacing it is
> > > the fact that it recompresses to MPEG-2 (the new Time Warner boxes
> > > apparently don't recompress digital cable - they just write
> > > the digital
> > > stream to the hard drive).  I think it's the MPEG-2 standard, and the
> > > fact that it's recompressing what's already been compressed and
> > > converted to analog once, that causes the image degradation,
> > > rather than
> > > any quality issues with the encoder/decoder.
> > >
> > > > -----Original Message-----
> > > > From: Max [mailto:max-mythtv-users at lasevich.net]
> > > > Sent: Tuesday, August 05, 2003 4:40 PM
> > > > To: Discussion about mythtv
> > > > Subject: Re: [mythtv-users] so how does Tivo do it?
> > > >
> > > >
> > > > First of all,don't take it personally, after all "lower" is
> > > > only a relative
> > > > term.
> > > >
> > > > And by components I meant stuff ON the motherboard. Things
> > > > like the mpeg
> > > > encoder/decoder , DACs, etc. - as well as other stuff like
> > > > quality of the
> > > > case (Series 1 cases were much sturdier than S2's),  and
> > > > quality of power
> > > > supply (many S2 power supplies cannot handle 2 harddrives,
> > > > where S1's were
> > > > actually DESIGNED to support 2 drives.) Also some components
> > > > present on S1
> > > > motherboards were removed for S2 - though for my life I
> > > > cannot recall right
> > > > now what they were.If you want more details, do some
> > >
> > > searches on Tivo
> > >
> > > > Underground forum.
> > > >
> > > > All in all, Series2 units seem to have more issues with video
> > > > and audio
> > > > quality than series1 boxes, and tivo themselves said that
> > >
> > > part of the
> > >
> > > > redesign goal was to reduce cost of the boxes.
> > > >
> > > > It is still a nice box though and quiet sufficient for task.
> > > >
> > > > -M
> > > >
> > > > > I'm not sure the component quality is really lower.  What
> > > >
> > > > is that based
> > > > on?  I have a series 2 unit that I've modified with a new
> > > > hard drive... all
> > > > that's in there is a power supply, motherboard with
> > >
> > > integrated CPU and
> > >
> > > > hardware TV encoder, one fan and one Western Digital 40GB
> > > > hard drive (I had
> > > > a 40 hour model).  I'm not even sure what there is that could
> > > > be considered
> > > > higher or lower quality than what used to be in there - there
> > > > are exactly
> > > > three parts to a TiVo that I was able to see, one of which is
> > > > solid state,
> > > > another of which is from a reputable and respected hard drive
> > > > maker.  And I
> > > > can't imagine they're making units with lower-quality power
> > > > supplies now;
> > > > that'd be an odd place to save money (or rather, it would
> > > > have been odd if
> > > > they were using particularly *good* power supplies in the
> > > > first gen models).
> > > > So I don't know where the lower quality assertion comes from.
> > > >  The weight of
> > > > the unit?  Size?  Looks?
> > > >
> > > > > As for how they do it, the only thing in there that's worth
> > > >
> > > > anything is
> > > > the hardware TV encoder, which is probably equivalent to a
> > > > PVR-250.  A 40GB
> > > > hard drive can be found for about $40 these days, the slow
> > > > CPU's they use
> > > > are basically worthless, and a cheap, generic motherboard
> > > > only costs $15 so
> > > > I can imagine they're not paying much for their custom PCB's.
> > > >
> > > > > >From their lifetime subscription fees, they're counting on
> > > >
> > > > at least $500
> > > > per customer over the life of a unit.  I guarantee they're
> > > > making a nice
> > > > profit at that price.  On the other hand, the company itself
> > > > is still losing
> > > > money, but that's more due to company size and overhead vs.
> > > > installed base
> > > > than anything.  If they had enough subscribers, they'd be
> > > > making money, and
> > > > I'm sure they're making money on a per-unit basis.
> > > >
> > > > > > -----Original Message-----
> > > > > > From: Max [mailto:max-mythtv-users at lasevich.net]
> > > > > > Sent: Tuesday, August 05, 2003 2:53 PM
> > > > > > To: Discussion about mythtv
> > > > > > Subject: Re: [mythtv-users] so how does Tivo do it?
> > > > > >
> > > > > >
> > > > > > Tivo is
> > > > > >     a: using custom designed, dedicated platform, not generic
> > > > > > multipurpose
> > > > > > hardware, so they only have needed hardware
> > > > > >     b: because of a, they can use a 75Mhz PPC w/ 16MB of ram
> > > > > > instead of
> > > > > > 1Ghz+ P3 with 512MB of ram
> > > > > >         (at least this is Series1 specs, Series 2 is
> > > > > > different I think)
> > > > > >     c: Series 1 units were sold BELOW their harware price,
> > > > > > they tried to
> > > > > > make up the difference in service fees
> > > > > >     d: Series 2 units have better spec, but use much
> > > >
> > > > lower quality of
> > > >
> > > > > > components as to bring the cost down.
> > > > > >
> > > > > > -M
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > From: "John Wells" <jb at sourceillustrated.com>
> > > > > > To: <mythtv-users at mythtv.org>
> > > > > > Sent: Tuesday, August 05, 2003 11:45 AM
> > > > > > Subject: [mythtv-users] so how does Tivo do it?
> > > > > >
> > > > > > > So, basically, if I want to create a MythTV box with all
> > > > > >
> > > > > > the features of
> > > > > >
> > > > > > > Tivo, I'm looking at a fairly hefty (at least $600+)
> > >
> > > price tag.
> > >
> > > > > > > How does Tivo offer their systems at such lower prices?
> > > > > >
> > > > > > I'm aware of
> > > > > >
> > > > > > > economies of scale, but what magic are they working?
> > > > > > >
> > > > > > > I suppose the monthly subscription fee covers some of their
> > > > > >
> > > > > > cost, but it
> > > > > >
> > > > > > > can't be a very lucrative profit there...
> > > > > > >
> > > > > > > Anyone have some insight?
> > > > > > >
> > > > > > > Thanks,
> > > > > > >
> > > > > > > John
> > > > > > > _______________________________________________
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> > > > > >
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