# Listening impressions of the Alpine PXA-H700/701



## GlasSman (Nov 14, 2006)

Ok I had had my PXA-H700 installed earlier this year for a few months but removed it along with the rest of the system and hadn't had it installed since.

Theres no question it's a versatile processor. Some people find some of the Para EQ features annoying, some have encountered noise issues, many say it's not Hi-Fi enough.

I won't comment on any of the features or what it can do since we all know what it can and can't do. Theres actually not much it can't do. It's more processor than most will ever need.

What I will be commenting on is the SOUND of the processor. Now I don't have access to countless pieces of mega buck gear but I have listened for considerable lengths of time to very high end, HIGH RESOLUTION systems. So I know whats possible with todays ubber expensive gear.

I can only comment on the differences it made on MY SYSTEM. While not top of the line it's a good choice of budget gear thats well over 10 years old with the exception of the Sony.

The system consists of: 

Adcom ACE-15 line conditioner

Sony DVP-S7700 DVD/CD player for playback - Top of the line DVD from around 2000(MSRP$1200)thats very well reviewed with Copper case and considered a solid CD transport with very good digital filters. Many that reviewed it said it should have the ES designation. That would surely have added to the MSRP...so I guess they did us a favor. 

Adcom GFA-545 II power amp

Adcom GFP-545 II preamp

Polk Audio Monitor 10 Series II - 2 6.5" woofers, soft dome tweeter and 10" passive radiator. Very well reviewed back in early 90's. Theres other spreakers I would have chose at the time but having a friend that worked at Tweeters I had access to many good deals. They've served me well for the past 17 years and a good match for my Adcom amp. 

This test stems from many comments made that that the PXA-H700/701 is not sonically as transparent as other processors and not designed as well as it could have been. I had doubts I would want to use it in my system again. So I figured...I'm happy with the sound of my home gear. Why not compare it directly to the filters in my Sony source unit. Sony doesn't make the best of everything. But they've done seversl things very right in home audio and the DVP-S7700 DVD/CD player is a good example of this.

To keep things fair I went into the Adcom preamp from the H700. I hooked the RCAs from the Sony to Tape1 and the RCA's from the H700 to Tape2. That way A/B comparisons were only one click away. And of course I hooked th optical from the Sony into the Alpine.

I hooked up the Alpine to a 10 amp power supply which is sufficient for a low level device such as this. 

I'll start by saying it introduced NO NOISE using the optical input. 

After adjusting the X-Over and being sure all EQ settings were set to flat and no Mx processing was activated, all input/output adjustments were made and correct speakers were selected I was ready to go. I level matched on the Alpine unit to the listening level I chose from both inputs. I arrived at a 32 volume level. 

I started out with some of the Zuki test discs and played some other well recorded CD's. 


On the Opeth CD Ghost Reveries I was pleasantly surprised at the things I was hearing. Fingers sounds on guitar strings were very well defined and not just a backgroung sound. That guitar player was closer to me. Everything was just presented with more resolution. The bass guitar was more up front, bass drum attack and decay was more defined, vocals were more up front and cleaner, cymbals details came through. Everything was more clearly defined and not as confusing. I'm a drummer, so I know what cymbals sound like. Cymbals went from a ping to "OK I can tell thats a medium weight cymbal and not a heavy cymbal. There were overtones that weren't present before. 

If any of you know the overhang you get with a nice sounding bass drum, well I heard this compared to a thud with the Sony filters. I felt on every recording I was closer to the recording studio. Like there was a piece of carpet removed from the front of the speakers. 

As I write this I'm listening to Opeth/Ghost Reveries Requiem/Harlequins Forest and my spine is tingling from the level of resolution presented to me. I'm astounded. I'm also spoiled since without the Alpine processor the system doesn't move me as much. I feel as though I just hear the music and have no involvement. The Alpine brings you in there.

I felt like I was listening to a different system. My speakers are capable of performance I wasn't aware of. I now feel good saving these for a secondary system in the future. 

On some not so stellar recordings there wasn't as much of a difference. But still things were clearer and sounded as if a veil was removed.

I haven't listened to nearly enough material as I'd like but I auditioned enough well recorded discs to have a solid opinion on the sonics of this processor. 

In conclusion I'll say this. I do not doubt the sonics of this processor anymore. Despite the flaws it might have from a design standpoint, I am now reassured of one thing:

It sounds DAMN GOOD!


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## req (Aug 4, 2007)

i would like to comment on the h701 and its rca interconnects.


having sound in the car without an optical cable for the input however, i do have induced noise. its not alt whine. its a scratchy high pitched buzz when the volume on the h701 is high and the volume on my 9830 is low. vice versa, it has a very very small but audible effect at high volumes.

im not sure how it is in other peoples installations - but i can not wait to upgrade to an optical output with DVDaudio support. and in the future HDDVDaudio  

but thats my 2 cents.


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## GlasSman (Nov 14, 2006)

req said:


> i would like to comment on the h701 and its rca interconnects.
> 
> 
> having sound in the car without an optical cable for the input however, i do have induced noise. its not alt whine. its a scratchy high pitched buzz when the volume on the h701 is high and the volume on my 9830 is low. vice versa, it has a very very small but audible effect at high volumes.
> ...


Check this out:

http://www.elitecaraudio.com/forums/showthread.php?threadid=87972&pagenumber=1


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## GlasSman (Nov 14, 2006)

This one needs a nudge to the top since it's such a popular unit and the best ALL- IN-ONE WONDER BOX.


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## MiloX (May 22, 2005)

I cannot disagree with that assesment. 

For the price, there is no better DSP available today. Yeah... there are some quirks. 

I am removing mine from the competition car and using the processing built into my amplifiers for next year. I am trying to minimize items in the signal path. 

I know for sure that the following class champions from IASCA and MECA finals this year were running the 701:

Joe Karpus
Andy Jones
David Brooks

Solid piece for the dollars. That's fo sho!


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## Scott P (Sep 9, 2007)

MiloX said:


> I cannot disagree with that assesment.
> 
> For the price, there is no better DSP available today. Yeah... there are some quirks.
> 
> ...


Brian how many people were using the Zapco Processing? I know Steve and Kirk are but not to sure after that. 

This also reminds me that I really need to get to ATL and persuade Jeff to teach me how to properly use mine. I've jacked the GEQ up something horrible.

Other than that I have to agree as well with the review. I can't think of a better value I've ever invested in (car audio wise)


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## GlasSman (Nov 14, 2006)

The Zapco DC Reference amps are the only solution I would consider to eliminate the H700.

I have to get my hands on a DC Reference just to do the A/B comparison.

I was blown away with the difference between the Sony D/A converters and the H700. 

If the DC Reference processing is THAT much better I might cream my pants.


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## thehatedguy (May 4, 2007)

If I sent you my DSP-6, you would want to get away from the computer while typing your review. It is not too far behind the Rane and my modded Bel Canto DAC2 in terms of sound...and both of those stomp the H900.


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## GlasSman (Nov 14, 2006)

thehatedguy said:


> If I sent you my DSP-6, you would want to get away from the computer while typing your review. It is not too far behind the Rane and my modded Bel Canto DAC2 in terms of sound...and both of those stomp the H900.


Well I might have been listening as I wrote the review but I did listen to over 6 hours worth of music over a 3 day period.

But I get what you're trying to say.


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## GlasSman (Nov 14, 2006)

Sonically this processor might be very low on the totem pole compared to other processors.

But it still makes me grin on a daily basis listening to recordings I haven't heard in a while.


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## demon2091tb (May 30, 2005)

Is there any way to get inside the 701 and change out chips, etc, upgrade or is this completely undoable?

J/w if its possible not that i'd even try......wouldn't know where to begin.


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## thehatedguy (May 4, 2007)

You can, but it's not really worth it.



demon2091tb said:


> Is there any way to get inside the 701 and change out chips, etc, upgrade or is this completely undoable?
> 
> J/w if its possible not that i'd even try......wouldn't know where to begin.


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## ErinH (Feb 14, 2007)

thehatedguy said:


> You can, but it's not really worth it.


I got the same response when i asked this a few months ago. Someone linked me to a thread on ECA where (I think) Scott Buwalda (sp?) had said he took a look at "upgrading" the 701 and concluded it just wasn't worth the hassle.


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## GlasSman (Nov 14, 2006)

demon2091tb said:


> Is there any way to get inside the 701 and change out chips, etc, upgrade or is this completely undoable?
> 
> J/w if its possible not that i'd even try......wouldn't know where to begin.


Some guy in Indonesia had several mods performed on his H700.


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## thehatedguy (May 4, 2007)

He's got about $240 worth of caps, $24 in opamps, and $200 in a new clock.

And it still hasn't addressed the major weakness in the 701- the volume control.

But if you guys want to throw $500 worth of parts at a $300 processor...go right a head.


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## Rbsarve (Aug 26, 2005)

I have been thinking of adding a clock upgrade to it with a synch wire to the 9861 that I'm currently running, since there seems to be some jitter issues going on there.

Sure it is a couple of hundred bucks more, but honestly the only thing I would consider upgrading to is the DEQX and that is a lot of hassle and more then a few bucks aswell...


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## GlasSman (Nov 14, 2006)

Rbsarve said:


> I have been thinking of adding a clock upgrade to it with a synch wire to the 9861 that I'm currently running, since there seems to be some jitter issues going on there.
> 
> Sure it is a couple of hundred bucks more, but honestly the only thing I would consider upgrading to is the DEQX and that is a lot of hassle and more then a few bucks aswell...



Well if the cash isn't a problem I guess it's worth doing. But the badly designed volume control should be addressed.


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## GlasSman (Nov 14, 2006)

Did some listening with Ai-Net into the PXA-H700 and things weren't so hot. More to follow......


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## Ace (Jan 29, 2008)

good info. im tryin to decide what im going to run in the truck


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## Ace (Jan 29, 2008)

thanks!!


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## ///Audience (Jan 31, 2007)

btw... theres a good thread on ECA about modding an h701.


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## GlasSman (Nov 14, 2006)

BassBaller5 said:


> btw... theres a good thread on ECA about modding an h701.


I saw that one.


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## LastResort (Oct 24, 2007)

I didn't see it, somebody want to point to it?


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## GlasSman (Nov 14, 2006)

LastResort said:


> I didn't see it, somebody want to point to it?


Let me find it.....


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## LastResort (Oct 24, 2007)

Thanks!


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## Pulse-R (Jan 14, 2007)

I'm in the process of modding my 701 output circuits as I am not happy with the resolution, noise and THD+N.

1. replace DAC with K-Grade version
2. replace output stage JRC opamps (12 or so of them) with OPA2134's
3. replace all electrolytics in signal path with Blackgate HiQ parts.
4. directly bypass output op amps with low ESR parts soldered close to caps.
5. replace built-in power supply (+/- 10V) with Clarion external +/-15V unit.
6. replace muting transistors with relay contact mute.

The volume control IC is the biggest let-down so eventually I'll replace the entire output chain including the DAC, for discrete 8 channel board which is currently in design stage. That will be AKM4396 DACs, LM4562 opamps, PGA2310 volume control, fully balanced 8VRMS outputs from DAC to power amp. now all I need is more free time


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## Rbsarve (Aug 26, 2005)

Good luck on that. I'm in the market for some more time per day aswell. If anyone sees it on e.bay gimme a hollar! 

Looks promising. I've been contemplating doing a cloc sync mod to it and my 9861.


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## Pulse-R (Jan 14, 2007)

I did look at changing the Xtal for a real osc, and may do that as part of the 2nd upgrade. The problem is the implementation; the circuit shows the DSP's and DAC running off the 'back' of the main clock signal, while the Dolby chip runs off the front of the clock, so 180deg. phase??!!... might have to look for a clock with complementary outputs, or experiment with using a single-phase one (hope it works - might ask around for opinions on that one).


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## Pulse-R (Jan 14, 2007)

http://forum.elitecaraudio.com/showthread.php?threadid=87972


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## GlasSman (Nov 14, 2006)

Pulse-R said:


> http://forum.elitecaraudio.com/showthread.php?threadid=87972


Thats the thread. Thanks.


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## doitor (Aug 16, 2007)

Pulse-R said:


> I'm in the process of modding my 701 output circuits as I am not happy with the resolution, noise and THD+N.
> 
> 1. replace DAC with K-Grade version
> 2. replace output stage JRC opamps (12 or so of them) with OPA2134's
> ...


If you don't mind me asking, how much $$$$$$ are you going to spend for all of the above?
pm me if you want.


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## GlasSman (Nov 14, 2006)

doitor said:


> If you don't mind me asking, how much $$$$$$ are you going to spend for all of the above?
> pm me if you want.


From what I remember it's not the money he's worried about....it's just the experience of upgrading and getting better performance from the unit.....if at all possible.


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## maxtox (Mar 22, 2008)

doitor said:


> If you don't mind me asking, how much $$$$$$ are you going to spend for all of the above?
> pm me if you want.


u've got pm...


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## GlasSman (Nov 14, 2006)

maxtox said:


> u've got pm...



Ok I have to know how much. 

PM away.


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## Pulse-R (Jan 14, 2007)

not sure on the total yet, I think about $400 or so. I got the Clarion converter for $60 (slightly used) as the main unit was stolen out of a guy's car... stupid thiefs!
Those 603 SMD resistors are a PITA to desolder... I have bypassed the output mixer stage, so the Navi Mix is out of the circuit. also changed some of the other bits along the way.

I'm making progress now, but the relays I got are the wrong type, so back to the shop next week for the correct ones. 

Also - the component values in the Service manual are completely different to what is used - for the worse generally.


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## GlasSman (Nov 14, 2006)

Pulse-R said:


> Also - the component values in the Service manual are completely different to what is used - for the worse generally.


So they probably used cheaper components when production time rolled around to save some money.

Thats VERY dissapointing that they would do this to such a dream box.

Skimp on the lower end CD's players.....not the ONE GOOD and affordable processor you manufacture.


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## Pulse-R (Jan 14, 2007)

Well, I have done some of the mods for now, the op amps and supply and signal capacitors.

The difference in sound is better resolution in the mid range, stronger bass and midbass, and cleaner top end.

seems that it was worthwhile.

I have found that my CDA-7998 is making its own noise on the optical output. I guess that's next on the hit-list.

If only I could get a schematic for the 7998 - the service centre here in Oz won't sell it to me.


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## SSSnake (Mar 8, 2007)

Did you measure the difference or just hear it?


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## Pulse-R (Jan 14, 2007)

I could hear the difference.

Previously the PXA was dull in the midrange and lacked a lot of life compared to my home DAC. Now, it is much the same as my home DAC. I could have spent 10 hours measuring and testing to write about the differences, but after all that is done it is the sound which has improved.

Description and photos here:
http://www.mobileelectronics.com.au/forums/index.php?showtopic=540401&hl=


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## GlasSman (Nov 14, 2006)

Pulse-R said:


> I could hear the difference.
> 
> Previously the PXA was dull in the midrange and lacked a lot of life compared to my home DAC. Now, it is much the same as my home DAC. I could have spent 10 hours measuring and testing to write about the differences, but after all that is done it is the sound which has improved.
> 
> ...


Well if the differences can be heard.....the upgrades are worth it regardless what some say.


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## GlasSman (Nov 14, 2006)

Pulse-R said:


> I could hear the difference.
> 
> Previously the PXA was dull in the midrange and lacked a lot of life compared to my home DAC. Now, it is much the same as my home DAC. I could have spent 10 hours measuring and testing to write about the differences, but after all that is done it is the sound which has improved.
> 
> ...


Sounds like the same difference going from the DACs in my home source unit to the stock PXA-H700.


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## GlasSman (Nov 14, 2006)

4th of JULY bump.


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## GlasSman (Nov 14, 2006)

Up for the new people.


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## GlasSman (Nov 14, 2006)

Bump for the newbs.


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## GlasSman (Nov 14, 2006)

Bump for the newbs.


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## basicxj (Jan 1, 2008)

GlasSman said:


> Bump for the newbs.


...and another bump.


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## GlasSman (Nov 14, 2006)

Uppity.....


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## matdotcom2000 (Aug 16, 2005)

This a good thread but I still wonder how this processor modded or unmoded hold up against the h900 and the bitOne


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## matdotcom2000 (Aug 16, 2005)

I found this on another forum that Quoted it from ECA not sure who but I thought that this would be a goodplace to put it

Taken from elitecaraudio. hope it helps.

DISCLAIMER : This is an engineering review of the Alpine PXA-H700 by an educated observer, based on the Service Manual. I will not comment on how it sounds, simply because I have never heard it. I will not comment on how friendly or flexible the user interface is, because I have never used it.

A few posts to cover : digital input up to the DAC, analog outputs, and analog inputs. I probably won't post links to the chips, but I will give the part numbers ... google can find the datasheets easily for anyone interested.

Digital inputs directly feed a Yamaha YSS932 chip which performs : DIR (Digital Input/Interface Receiver), Dolby Digital/Pro Logic II/DTS decoder, Sub DSP. Now the job of the DIR is to recover clock, and separate the data from the incoming S/PDIF stream. I've talked about this before ... yes, the H700 uses a recovered clock for digital audio timing, rather than an Asynch Sample Rate Converter ... but so does it's big brother the H900, which uses the industry-standard CS8412 chip, for clock recovery.

Now we would expect that the recovered clocks (along with the digital audio data itself, after further DSP processing) would ultimately feed the DAC chip. And they do, but not until something very puzzling happens.

First, a quick review of clocks that DACs like to see. There are typically 3 : LRCK, BCK, MCK. LRCK is the Left/Right clock or "word clock" used to tell the DAC a new digital word is coming, and if it's stereo left or right. BCK is the Bit clock used to clock or latch all the bits for each word into the DAC. Finally, MCK is the Master clock upon which all DAC timing ... including the all-important conversion to analog ... occurs. These 3 clocks, recovered from the S/PDIF stream, plus the audio data itself, form the very common "4 wire" interface to a DAC.

Now all three of these clocks are supplied by the Yamaha chip, and find their way down to the DAC chip ... with ONE very important exception. The Master Clock is interrupted ... and sent to the last page in the page in the schematic (4/4) for some processing ... before it comes back as the Master Clock input to the DAC.

The processing performed on the Master Clock is quite interesting. MCK (out of the Yamaha chip) feeds (along with the other clocks mentioned) a Toshiba TC9271FS digital audio TRANSMITTER chip, whose output feeds ... a Crystal CS8412 digital audio RECEVIER !!! And the 8412 ultimately provides the Master Clock to the DAC. What's especially interesting is that the Toshiba transmitter NEVER sees digital audio data ... it's sole function in the H700 is to provide a S/PDIF "type" signal, based solely on clock inputs, to the input pin of the 8412 ... which is expecting an S/PDIF signal, from which it recovers a clock.

Why on earth would Alpine do this? We find a BIG clue on the names given to the 9271 & 8412 in the Service Manual ... "Residual Noise Improve". What's of further interest is that the "interruption" of the Master Clock signal, and the fact that the last page of the schematic (Page 4/4) contains ONLY these couple of chips for "Residual Noise Improve", indicate that this function was a late CHANGE to the H700.

Well, i just don't know enough to be convinced about my noise theory on the analog inputs. It sure seems that the clock recovered from the incoming digital S/PDIF stream in the Yamaha chip gets "cleaned up", as described, before it drives the DACs. And the same clock node, before "cleaning", is the master clock for the ADCs.

But the question is, what is the nature or genesis of this clock WHEN THE ANALOG INPUTS ARE "ACTIVE"? In other words, it seems unlikely that this clock output from tha Yamaha chip is actually recovered from an incoming S/PDIF stream when the ANALOG inputs are being used ... because there might not even BE such a digital stream into the H700 when it's looking at the ANALOG inputs. But the Yamaha chip must generate the clock somehow, because it IS used by the ADC. There's only a few options :

1. You really do need a valid S/PDIF stream on the digital input, even when the H700 is observing the analog inputs. Users can help answer this one

2. The PLL inside the Yamaha chip switches to a different clock source, when no S/PDIF stream is present, to supply a MCLK output. One candidate is the separate crystal oscillator used by the Yamaha chip to operate internal DSP operations. I might be able to figure this out from the Yamaha data sheet.

And if the second point is what really happens inside the H700 when the analog inputs are used, it's not clear that the clock would be as "dirty" when the analog inputs are used ... maybe, maybe not ... so, for the time being, the ADC clocking must remain an "unproven hypothesis" for analog input noise.

But one thought I have regarding the "poping" or clicking noise during volume changes. Especially since it's worse at high volumes ... this may be a classic case of so-called "zipper noise" ... essentially the audible artifact of "step" changes in volume with electronic (that is, not analog potentiometer) volume control chips.

Generally speaking, there are two ways to combat zipper noise :

1. Algorithmically "ramp" the volume in a gentle fashion when the user requests a volume change. This must be implemented in a DSP chip inside the unit.

2. Wait for a "zero crossing" of the signal, before you implement the volume change requested by the user. The signal will NOT have an abrupt level change ... the culprit of zipper noise ... if the gain change occurs when the signal is zero This can be implemented in a DSP chip inside the unit, or there are some volume control chips (like the lovely Wolfson) that have this function built-in.

Now I recall in my review of the H900, that the volume control chips used did NOT have any of these options in them. So we concluded that the DSP chips in the H900 must be implementing one of the two above algorithms to avoid zipper noise (since there have apparently been no complaints of zipper in the H900).

So here's a speculation ... perhaps, since the DSP horsepower of the H700 is of course less than that of the H900, some shortcuts were made in the volume control algorithms? I know that's not a very satisfying answer for the user 

What exactly is this function? Why interrupt the Master Clock from the Yamaha chip on it's way to the DAC, send it through a digital audio transmitter/receiver pair, before sending it to the DAC? I think there's only one reason : JITTER. I suspect ... it's only a suspicion guys ... that the Master Clock provided by the Yamaha chip had too much jitter (phase noise, timing inaccuracy), and Alpine solved it by sending the clock through an industry standard device for FILTERING clock jitter ... namely the CS8412. Further, I suspect this was a LATE addition to the H700.

Was there anything in the press from Alpine, about noise problems discovered late, which required hardware revisions or fixes? If so, here it is

Alright, on with the tour. Next up, the DAC. Alpine uses a Burr Brown/TI PCM1608 24-bit, 8 channel DAC chip in the H700. Here's some relevant specs :

Dynamic Range : 100dB typical (PCM1608Y, used in the H700)
Full Scale THD + Noise : 0.008 %
Digital Filter passband ripple : +/- 0.03dB
Digital Filter stopband rejection : 50dB

Now if you're looking at these specs and wondering what exactly about this DAC is "24 bit", other than the fact that it accepts digital words with 24 bits in them, well .... you're not alone

So let me say that the Alpine H700 is built to a price point well below some other processors out there ... OF COURSE ! Not surprisingly, it's NOT in the same league as the H900, from a COST or engineering execution perspective.

Anyway, next up we'll talk about analog outputs & inputs.

And now about those analog inputs on the H700. Well, first I traced all the analog circuitry up to the ADC, which is a PCM1801 Burr-Brown/TI, 16 bit ADC. Did I ever tell you guys that analog circuits are my first true love? Shhhh ... don't tell my wife

Now Alpine follows a VERY GOOD practise in both the H900 and the H700 on their analog inputs ... I'm not sure how wide-spread this is in the industry, but it should be. The "ground" lead of the RCA inputs is fed, right along with the "hot" lead of the RCA inputs, to a circuit commonly called a "differential-to-single ended converter" ... just a nifty little opamp circuit, that only measures the DIFFERENCE between the RCA-hot & the RCA-ground, providing a single-ended output that is essentially "re-referenced" to a NEW ground inside the H700. In the H900 Alpine calls this circuit an "input isolator", and it acts JUST like the input of a BALANCED receiver would. So-called "common mode" noise ... noise on the RCA hot & ground leads ... is rejected, leaving only signal. So even though the input is NOT balanced in the sense that you don't have positive & negative going signals driving the H700 (at least at the RCA inputs ... the AiNet inputs may be truly balanced) ... the RCA inputs are "observed", within the H700, as if they WERE balanced ... which should give great noise rejection, and avoid ground-loop type noie problems with the RCA inputs.

Now I was puzzled abit because the "new" ground that the analog inputs are "re-referenced" to inside the H700 seemed a bit strange ... it's generated from a buffered resisitive divider between "VCC" and "VEE", heavily bypassed by a big cap to VEE. The important thing, from a noise perspective, is that this must be the SAME signal used as a ground reference in the PCM1801 ADC ... and sure enough, it is although sometimes called by a different name on the schematic.

So the analog input circuitry looks fine to me Why did I bother telling you all this stuff? Hell if I know ... just needed to justify the last half hour of my life.

OH YEAH .... I almost forgot to mention. Remember in my post about the MCLK out of the Yamaha chip, needing to have it's jitter filtered by the strange S/PDIF transmitter/receiver pair ? (Hee hee ... that Yamaha chip needs to have it's clock cleaned ... hee hee). Guess what clock feeds the ADC that converts the analog inputs, the pre-filtered (dirty) clock OR the post-filtered (clean) clock? You guessed it ... the DIRTY clock. Don't know why, only the DACs get the clean clock. Maybe need to look no further as to why the analog inputs are a bit noisy


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## GlasSman (Nov 14, 2006)

matdotcom2000.....thanks for saving that bit from ECA.

We lost alot of great info when that site went down.:mad;


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