Anyone cares to post images of his upgraded CD-7 ? I wonder how the managed to fit the 5881 tube inside the CD-7, which has a bit different PCB layout.
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Nice pix of the inside of the player. But I'm compelled to say that I am a bit underwhelmed at the layout of the PCB inside the CD8. I know that sound is the ultimate goal and I don't mean to dis your nice player. It's just that the tube analog section doesn't seem isolated from both the PS sections or digital sections. Is the analog section that robust? And the position of the large rectifier tube seems a bit odd. I wonder how the wires are routed underneath the PCB- going all the way across the PCB from the 120VAC Tranformer to the rectifier tube. I have and appreciate my ARC gear so don't take me as being mean spirited. Others with more electronics knowledge than me may have some ideas for some quick and easy tweaks for your player. |
Many people here saying CD8 is better than CD7, but how manny of them had a PS CD7 fault and don't know about it. I'm pretty sure my did not have this problem after ~ 800 hours (my came with the upgrade 6H30 board installed from the factory). Not long before I sold the player, I have put a brand new set of tubes (all 7), just to see how much the original tubes deteriorated with time, only to find out no real difference in sound quality between the two sets. So, as far as I'm concerned, the CD-7 was one of the best, if not THE best CDP I have owned so far - both sound quality and reliability wise. |
I think 6550 is more powerful than a 5881 (that is a smaller version of the 6L6), This tubes are being used in the PS so they are not in the path of sound, but as a part in the PS. As long as there is enough power for the audio circuits I don't think they will make any change in the sound result. But the malfunction of then (like what was happening with the two 6H30) will affect sound. Many people here saying CD8 is better than CD7, but how manny of them had a PS CD7 fault and don't know about it. What people is saying is that a CD7 with the last update and CD8 the difference in sound is not big. |
During the last days the CD8 has become somewhat bright, sibilants seem enhanced. I hope that after burn in the tonal balance becomes fuller again! This is the same rollercoster I expirienced whan I was breaking in my old CD-7. The sound was changing from dull to bright and vice versa. This is why I resisted the temptation to listen the the player fresh out of the box. Based on your expirience with CD-8, I may even extend the initial burn in from 10 days, to full 20 days. It will give me more time to play with the dCS Puccini I still have on loan. |
Just got the CD-8 today. Here are some inside images of the new design with 6550 tube in the PS: Inside View 1 Inside View 2 The DAC chipset used is 24/192kHz capable PCM1792 from Burr-Brown: Inside View 3 Now I'm gonna leave the player in a repeat mode 24/7 for the next 10 days or so before I start any listening. By then the player should already have around 240h of play time, although based on my expirience with CD-7, I reckon that it will need additional 200h to fully break in. |
Although it is still too early to have a definitive opinion - my CD8 has only around 250 hours continuous playing time with same breaks - it is now very different sounding from the CD7. The sound balance is different, the CD8 bass has better definition and resolution. During the last days the CD8 has become somewhat bright, sibilants seem enhanced. I hope that after burn in the tonal balance becomes fuller again! |
This is like having an entirely new CD collection. Now I'm thinking ... Do I dare sell this player and get the CD-8? I'm kind of thinking, if, as my contact at ARC says, the modded CD-7 gets you 25% of the way to the CD-8, and I get the CD-8, will I ever leave the house again? Will I sell all of my thousands of records, dump the turntable and phono-stage ... and just be done with the whole vinyl thing? To me, CD8 is one of the best sounding one-box digital players, remarkably better than already very good CD7. I used to write my views for CD8 under this forum topic. I also wrote as "it reduced the gap between my analog and digital sources, it is that good." But I would not sell my analog equipment and my records for CD8. My analog source is still my reference in terms of getting maximum satistaction. In terms of soundstage, seperation of instruments, inner texture and timbre, air and definition of high frequencies, a good analog is still superior, but it is nice to hear newcomer digital sources are closing the gap. |
What I´m saying is not about last update, I did not installed the 5881 update yet. I´m saying that mine CD7 have the last update before this one and the player sound better when it was new (before having the 6H30 problem). I can´t say nothing about this upgrade I did not hear any CD7 with it yet. I´m hoping this will bring my original CD7 sound back. Also I think many guys here have the problem and dón´t know about it, so when the unit gets fixed they think it´s an sound upgrade, but maybe it´s only fixing the bad sound that goes out when one of the 6H30 drift from the other one. |
Ossocao- Thanks for your perspective. I was plaining to send in my CD-7 for the PS update today, but now I'm not so sure whether to do this or not... Most people on this Board have said that the PS update improves sound, especially bass, but you clearly say otherwise. Should I go forward with the PS update?? I don't want to do this if it will make my sound worse!! |
Well guys I see most of you dont know the full history of these. ARC is trying to correct the PS problem in the CD7 for the last two years. What you are seeing is not an upgrade, but a fix. Mine original CD7 was sttuning, live music, belive me. After sometime when I tested an SE pre-amp I noticed a hum. ARC send a kit (still in my player), a revision: 4 resistors were replaced on the side of the 6H30s and one added, a board was puted over the two sockets and two new 6H30s installed on this board. The sound of the CD7 moded by ARC this way never got close to the original, no life. I hope this new kit (5881 tube) is all you are talking about. If not most of you only fixed a bad project problem. Note that the hum can only be heard in SE output. |
To continue ... I had two friends over to hear the upgraded CD-7. To say that I had to pry their jaws off of the carpet is an understatement. Both are very familiar with my system. One arrived late, and as he walked into the room and after hearing only a couple of notes, he immediatly said: "Now there's a tweak that is amazing!" I put on the Bach Tocata on the EMI Classic disc and that's when the jaws hit the floor, mine included. Does this revamped player play bass? In a word ... YES! I put on another disc on the Brainbridge label, Stephen Kates on cello. None of my previous players; CD-III, CD-IIImk-2, or the stock CD-7 could handle the lower register of the cello on this disc. They simply crapped out. The modded CD-7 not only handled the low notes, it put them right through my chest! I'm still in disbelief over it. I had always thought the amp was running out of power on this disc, even though I have 100 watts and 94db efficient speakers. Looks like the majority of CD players just aren't up to the job on these Brainbridge CDs. Same thing with the lower registers of a well recorded piano. I have some simply miked piano recorded at local concerts ... and let me tell you, THIS is a piano! A piano right in the room! This is like having an entirely new CD collection. Now I'm thinking ... Do I dare sell this player and get the CD-8? I'm kind of thinking, if, as my contact at ARC says, the modded CD-7 gets you 25% of the way to the CD-8, and I get the CD-8, will I ever leave the house again? Will I sell all of my thousands of records, dump the turntable and phono-stage ... and just be done with the whole vinyl thing? Save me! I'm lost! |
I also got my CD 7 back from ARC a few days ago. If you read WSILL and OREGONPAPA's comments they have hit it right on the "head" with the new performance achieved. It really is a new listening experience. I highly recommend any original owners to upgrade their players. The turn around time was only two weeks. Great service from a great company. The only thing I can't figure out is why they didn't include a power off button on the remote like the Ref 3 has??? I wish I could turn it off from my chair. Does the CD 8 include one on that remote? |
I just recieved my CD-7 back from ARC with the upgrade. Will was right on in his assessment. I only had time to listen to a few "cuts" before I had to leave, so anything I say here was with less than an hour on the player. Its operating on "repeat" until I get home tonight. The improvement is NOT subtle at all ... in fact, from my limited time listening today, what occured to me was ... this is like going from a mid-grade Grado cartridge to a very good moving coil. In comparison, inner-detail is much improved, like hearing around the notes of a classical guitar. Dynamics are much more explosive ... try the Jessica Williams "Live at Yoshi's" piano trio, both Vol-I and Vol-II. Amazing. My contact at ARC tells me that the modded CD-7 gets you about one-quarter to one-forth of the way to a CD-8. All I can say is, the CD-8 must be something speciall indeed. I'd recommend the upgrade mod to anyone who has a stock CD-7. Original owners get the mod for free. Take care guys and happy listening. |
For those who made the CD7 upgrade. Mine was already upgraded with a board on top of the two 6H30s slots. I had to change 4 resistors on the board, add one, put the board and installed two new 6h30. I heard the 5881 upgrade the tube is puted horizontally. Does it have a new board on top of the 6h30 slots to hold the 5881? Can someone send me some pics? I'm not in the US so i have to see if it can be done on field. |
The two 6h30 problem drift was solved with an upgrade kit that was fitted by my distributor free of charge, after I noticed some hum in the CD output when used in single ended mode. This was traced to a defective 6h30, but after this upgrade I had no more problems. Before parting with the old CD7 I checked the tubes - after 2500 hours they still measured as new. Although the CD8 is still burning-in, one thing is sure - bass is better articulated and more controlled. Three walls in my room are 2 feet wide solid stone and there is almost no bass absorption. As I am currently using Soundab A1PXs, bass performance is critical and the difference between the two players is easily noticed. |
What I've Learned: I spoke with Leonard at AR and asked him if this upgrade is a sonic improvement. He advised that it addresses a specific issue: if the existing two tubes in the power supply drift apart in their values this can cause noise. By going to a single tube instead of two tubes, this is eliminated. Because AR is covering this at no charge, I would imagine that they see this as correcting a problem. |
The CD8 output is 1.8V RMS RCA and 3.6V RMS XLR . The CD7 is 2.7 and 5.4V RMS respectively. I am using the Purist Audio Design System Enhancer CD for break-in, so I hope that after 100 hours the CD8 will be listenable. I went through two CD7s and I still remember how disappointed I was when I replaced one with more than 1000 hours play by one taken from the box. My perception after a few minutes listening is that the CD-8 is more detailed and has better bass definition - air moves faster - the fly at track 10 minute4'44'of Paniagua LaFolia is clearly heard! |
My CD8 is now spinning the Purist Audio Design System Enhancer in repeat mode and I will wait at less 24 hours before listening to it. I just measured it and did a spectral analysis to be sure everything was correct and comparing it to the CD7 could find that the CD8 output level is 3.5dB lower, as I confirmed later from the respective manuals. When comparing these units one must carefully match the volume, otherwise the CD7 is much louder! |
Interesting. My hybrid CD7 also came with the dimmable display and LED indicator features so its looking like I did get a lot of CD8 parts after all. Sonically it is sounding even better with superior bass definition and extension, more neutral midrange with seemingly more detail and overall better soundstaging. In my setup from what I recall the standard CD7 used to bunch images a little at the center and close to the speakers. My unit spreads the image more naturally and seamlessly between and outside of the speakers so that it is easier to pinpoint each instrument's exact location (laterally, vertically and front to back )in the soundstage. So far ARCs description of the improvements appear to be right on the money as the CD8 should be even better (hard to imagine) in this regard. |
ARC finally replaced CD7 with CD8 in their web site but still it does not appear under new products, also the technical specs are still missing. I copy paste CD8 from their web site below: REFERENCE CD8 Compact Disc Player We are proud to introduce a model that may be the most musical and musically accurate single-chassis compact disc player, the Reference CD8. It replaces a product that was still garnering five-star reviews three years after its introduction, the esteemed Reference CD7. With the advent of the CD5 and DAC7 in 2008, we knew that the DAC used in our Reference player needed a newer, higher-resolution version. (The new 24-bit, 192-kHz chipset is not retrofittable to the CD7.) And, our engineers found a way to physically incorporate the same power-supply regulation used in the Reference 3, using a single 6550C to replace two 6H30 triodes, giving better performance and longer tube life. Other enhancements include our newest output coupling capacitors and special damping tweaks. The playback mechanism continues to be the unsurpassed Philips PRO2R — still the best dedicated CD mechanism available. The REFCD8 also features a new dimmable display, allowing five levels of illumination or completely off. A small LED indicator remains lit when the player is on, as a reminder to prevent the player from being left on inadvertently. In size, input and output configuration, —and in all other operational functions, the REFCD8 is identical to the REFCD7. But there the similarities end. Sonically, the REFCD8 stands in a class all its own. While retaining the lush, full embodiment of the CD7 sound, the CD8 adds new dimensions of transparency. It immediately shows greater transient speed top-to-bottom, purer resolution of low-level detail and expanded dynamic contrasts, with more bass slam, definition and extension. The soundstage is larger and more holographic because of the heightened ability of the REFCD8 to embody and locate instruments and voices. Rhythmically, the REFCD8 also picks up the pace compared to the CD7, with improved timing cues and better rhythmic interplay. You will find other sonic dimensions to marvel as you spend time with this enticing player. Quite simply, the REFCD8 will have you rearranging your compact disc collection all over again as you rediscover and reprioritize old and new favorites. It really is the most mesmerizing, musically accurate CD player we have ever experienced — and what better way to bring enhanced value to a growing, and costly, CD collection! |
Mkilpi, I might say CD8 was not fully burned-in so that the frequency extremes might get even better, but I can clearly say the bass definition of CD8 is superior. It is faster and a bit more neutral in texture so that CD7 is trying to catch the timing and a bit lacks and feels like a bit heavy and boomy. I never felt CD7 had a lack of midbass weight, and indeed it was the player which had more weight and emphasis on midbass. While CD7 was louder and heavier in midbass, CD8 had a better control, faster and deeper (and probably lower) bass definition. So compared to CD8, CD7 sounded darker. On the other hand, CD8 did not have a tonal preference. The CD7 unit we tested did not have upgraded power supply kit. So, I cant comment on whether the new power supply or new DAC of CD8 or both of them creating the difference. Given Wsill's comments for power supply upgrade of CD7, I assume an upgraded CD7 performs better than original CD7. So, a comparison of an upgraded CD7 with CD8 will be more meaningful to evaluate the CD8. Best Regards. |
Number95, when you compared CD7 to CD8 in your system, did you notice that CD8 is better in midbass power, weight and body than CD7? I own CD7 and sometimes I feel this is the only (relatively) weak point in CD7. I think that this little lack of midbass weight is sometimes caused by excessive warmth in midbass region. thanks. |
I actually just purchased one of the last CD7's available for sale from Audio Research. I went for the CD7 instead of the CD8 because I got a great deal on the CD7 with a trade in against my CD3 MkII and was also told by my dealer that the machine I was getting was a hybrid unit incorporating many of the design changes implemented for the CD8 with the exception of the new DAC; essentially a CD8 without the DAC upgrade. I guess it makes sense that as the factory ran out of parts for the old unit they would incorporate whatever parts could be directly substituted from the new unit in the last production run. While I have no way to verify this, the new unit delivered to me came with the new power supply already installed instead of an upgraded older power supply so I have to assume that what I was told was at least partly correct. (I also received the CD7 manual which referenced the CD7 tube complement instead of what was provided with my unit). I have not had a chance to directly compare my unit to a CD-7 and have only run it for about 60 hours so far, but from memory of using a borrowed CD7 in my system I can already support the comments made regarding the performance of the upgraded CD7 and CD8. Notwithstanding the deficiencies of aural memory, there is definitely a more detailed, livelier sound with better soundstaging along with the impression of a slightly more extended, tighter bass. In fact the improvements are so much so that I was compelled to tweak the position of my speakers away from the back wall and further apart, something I did not feel inclined to do with the borrowed CD7. Performance should dramatically improve with break-in so I assume I am hearing only the tip of the iceberg. It is not clear how much of a difference the DAC makes but assume that the CD8 will be even better than my unit. If someone ever has an opportunity to compare an upgraded CD7 to a CD8 I would be interested in the results. For now and into the foreseeable future I am in music lover heaven! |
As I typed before, I had a chance to get a CD8 and CD7 for the weekend to home and experienced these two with my audio setup. My system basically is ARC gear, Ref-3 and Ref-610T monos. A couple of weeks ago I tested Ref-7 and found it has a better synergy than my Audio Aero Prestige. Now it was a better and more exiting test, comparing the successor of Ref-7 and Ref-7. CD8 had approx 150 hours of burning while Ref-7 had 500+ hours. One can argue that CD8 needs much more hours to perform its optimum. I also invited some audiophile friends to compare these two players. I did not reveal which player was playing to the listeners until the end. So it was player A vs player B. The conclusion was very straightforward. I guess it is a fair to say CD8 is a better player with a margin so that there is no doubt. I was expecting it to improve the virtues of Ref-7 to some margin but we found CD8 as a remarkably different sounding player than CD7. CD8 is fast, I mean really fast compared to Ref-7. Ref-7 seems like having a larger soundstage with larger instruments but in terms of accuracy and pinpoint imaging CD8 did everything right. CD8 has a darker background, better resolution in resolving instruments and inner details. Highs are better defined. It has a better authority and control over any frequency band. CD7 plays more forward compared to CD8. CD8 has a sounstage deeper and more behind the speakers. It is more effortless. At the end of the listening test we also compared CD8 with my analog setup (Acoustic Solid Royal tt, Graham Phantom tonearm, Transfiguration Orpheus cartridge, ARC PH-7) to see really how close it gets to analog which is my current reference source in my setup. I might say CD8 is one more step closer to analog presentation than CD7. There is still a gap between my analog and my digital sources but it is narrower. So to me, CD8 is that good. CD8 is my new digital source. |
I also think Dweller are right. It seems that ARC have a development strategy with module solutions. My guess is that we soon can see a Ref PH8 (PH7 with the "new" power supply and?) CD5's DAC is technical better but many still prefer CD7. My guess is that CD8 is the best of both. Next major upgrade of Ref3 show the future. ARC's strategy is little tireing. DCS for example have another customer care philosophy with free software upgrades for longer lifecycles. |
