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回覆 (17): Aqvox Phono
Why not call it premature ejaculation (PE), at least it is more common.  
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Only now, do I fully understand why we had PE class when we were young. Thanks Eddie!
Derek2A3
14-01-25
10:46:47
回覆 (16): Aqvox Phono
 
>From manufacturer. Any opinion?<  
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>Why not called it current ejaculation-CE, at least it is easier to understand.<  
 
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The signal coming from phono cartridge are like grapes that had to mature, harvest, ferment before they become wine. Why not call it premature ejaculation (PE), at least it is more common.  
evp1312
14-01-25
01:05:58
回覆 (15): Aqvox Phono
 
Why not called it current ejaculation-CE, at least it is easier to understand.  
 
kh33
14-01-23
18:29:32
回覆 (14): Aqvox Phono
>From manufacturer. Any opinion?<  
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Since you have the phono already, my not so humble opinion is just listen and judge it for yourself, rather than believing the BS put out by the manufacturer.  
 
Have you ever heard a manufacturer saying his products sucks? ;-)  
 
thekong
14-01-23
16:27:30
回覆 (13): Aqvox Phono
The vinyl disc, dinosaur of music recording formats, only barely survived the CD. Today, however, the quality of turntables, tone-arms, and cartridges have increased to unprecedented levels, which vinyl recording producers support by pressing higher quality discs in limited quantities. This means new challenges as well as new opportunities for phono amplifiers.  
 
The only consistent way to process the delicate music signal from a moving coil cartridge is with a balanced Current Injection (CI) input as the cartridge's signal is among the most sensitive an audio amplifier circuit will encounter. Using CI, the current of the moving coil flows through the phono amplifier, including the first half of the RIAA equalization. The result is a level of dynamics, impact, spaciousness and richness of color that surpasses the performance of step-up transformers as well as the usual voltage inputs.  
 
At the same time, Current Injection electrically damps the moving coil cartridge by letting energy flow into the CI input, instead of eliminating it in a cartridge load resistor. Transformed energy sounds different than and superior to eliminated energy.  
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From manufacturer. Any opinion?
dkyyu
14-01-23
14:21:41
回覆 (13): Aqvox Phono
The vinyl disc, dinosaur of music recording formats, only barely survived the CD. Today, however, the quality of turntables, tone-arms, and cartridges have increased to unprecedented levels, which vinyl recording producers support by pressing higher quality discs in limited quantities. This means new challenges as well as new opportunities for phono amplifiers.  
 
The only consistent way to process the delicate music signal from a moving coil cartridge is with a balanced Current Injection (CI) input as the cartridge's signal is among the most sensitive an audio amplifier circuit will encounter. Using CI, the current of the moving coil flows through the phono amplifier, including the first half of the RIAA equalization. The result is a level of dynamics, impact, spaciousness and richness of color that surpasses the performance of step-up transformers as well as the usual voltage inputs.  
 
At the same time, Current Injection electrically damps the moving coil cartridge by letting energy flow into the CI input, instead of eliminating it in a cartridge load resistor. Transformed energy sounds different than and superior to eliminated energy.  
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From manufacturer. Any opinion?
dkyyu
14-01-23
14:21:34
回覆 (18): Aqvox Phono
input circuit that allows its RCA inputs to operate in a balanced configuration  
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So one terminal is in the open naked for the fingers touch at the RCA plug/socket. That's kind of sexy!
bobui
14-01-20
10:09:40
回覆 (17): Aqvox Phono
>Maybe they put the input signal into a balanced stage.<  
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Not really, as both of them stated the inputs stages were sigle end in the manuals . Actually, the IO also provides XLR jacks for the input, but it is really single end.  
 
The ARC Ref 2 SE phono only have RCA inputs jacks, but they stated:  
 
"The Reference Phono 2 SE is a fully balanced design with an input circuit that allows its RCA inputs to operate in a balanced configuration without requiring an inverter"  
 
 
thekong
14-01-20
08:41:59
回覆 (16): Aqvox Phono
switching mode! That alone is already .................................  
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........not a very attractive proposition.  
 
Balanced source  
Is where each terminal of the source has balanced and equal impedances to ground. Connection for balanced therefore require two identical signal wires plus an overall screen. There is nothing magical about it and room for any principle alteration is very limited.  
 
To maintain this balance, the input stage and in this case the phono amp must need to have its stray impedances precisely balanced to ground which usually is based on either a differential pair or a transformer. In many professional audio, transformer would be more commonly used as the cost is of less important. Two very commonly used transformer manufactures that offer carefully designed transformers are Lundahl and Sowter.  
 
 
I myself wouldn't be too let down by the use of transformer. After all, an mc cartridge is build around coil and magnet! Right! Oh, a needle and a tiny piece of diamond too if you shall insist!  
 
bobui
14-01-18
09:43:42
回覆 (15): Aqvox Phono
I always wonder why there are not more phonos with true balance input! Even some supposedly full balanced phonos (like the Aesthetix IO and Pass Xono) used single end at the input stage, and then convert the signal to full balanced after that.  
 
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Maybe they put the input signal into a balanced stage. You only need to wire two pins in XLR plugs for the phono. The ground pin is left, but you have the ground cable separate. Maybe you connect via RCA to the Aesthetix and the XONO and internally they are wired ballanced. Just a different plug... I don't know, just an idea...
der_yeti
14-01-17
21:08:54
回覆 (11): Aqvox Phono
The Aqvox phono's power supply is switching mode! That alone is already .................................
Derek2A3
14-01-17
17:40:30
回覆 (15): Aqvox Phono
As a DIYer, I think you should hardwire all interconnects and speaker cables directly to the circuit and get rid of all those plugs lor! :-)  
 
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Total agree! No question. Plug and interconnect cable are necessary evil! If one can get rid of them. Why not?  
 
I have a plan to build two massive mono integrated amps that can stick to the back of each speaker to shorten speaker cable and get rid of the interconnect! The only problem is, cant work out how on earth I can get or diy a dual mono source lor! Be it CD or LP!
bobui
14-01-17
10:54:33
回覆 (14): Aqvox Phono
>This results, compared to the unbalanced mode, into more clean and relaxed, yet transparent presentation.<  
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I always wonder why there are not more phonos with true balance input! Even some supposedly full balanced phonos (like the Aesthetix IO and Pass Xono) used single end at the input stage, and then convert the signal to full balanced after that.  
 
Some say it was due to cost, but it seems unlikely that they spent all those money on full balance gain stages, only to leave the input stage in single end mode!  
 
The more possible reason is that it is hard to get the noise down with a full balance input stage due to the ultra-low signal. However, if full balance circuit is supposed to have lower noise, why it doesn't apply here?  
 
 
>It really is not balanced amplification that is a must to me but NO RCA is for sure lor! <  
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As a DIYer, I think you should hardwire all interconnects and speaker cables directly to the circuit and get rid of all those plugs lor! :-)  
 
thekong
14-01-17
10:35:05
回覆 (13): Aqvox Phono
Ah! I see, I see! You know, the thing is, I hardly read!  
 
Anyway, I total dislike RCA plug and have abolished all my interconnect and opt for XLR a while back. It really is not balanced amplification that is a must to me but NO RCA is for sure lor!  
 
For coaxial, I really like BNC with its small thin pin and twist lock. Very Pro!  
 
 
bobui
14-01-17
10:30:36
回覆 (12): Aqvox Phono
>but who is Fremer? <  
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Michael Fremer is a popular reviewer (I don't want to call him expert) in Stereophile , who did most of their analogue reviews in the past 10-15 years.  
 
 
thekong
14-01-17
10:18:40
回覆 (11): Aqvox Phono
Hi, dear all, thanks for all comments and opinion. The manufacturer and most reviewers mentioned the balance input works and sounds far superior.  
 
Before taking risk to re-terminate my tone-arm cable, I have ordered the RCA-xlr adaptor from Aqvox to testify the balanced input quality using my RCA arm cables. However, in their opinion, no matter how good the RCA tonearm cable, it will still possibly bring in some noise and may not be ideal to meet discerning audiophile, so they urge me to go for a balance tonearm cable for best results. My problem is, most of my tonearm cables are one-length RCA, I have high hesitation go rewire the whole bloody thing. So re-terminate the RCA to xlr seems sensible in my case.  
 
dkyyu
14-01-16
23:19:27
回覆 (10): Aqvox Phono
In my opinion the Aqvox phonostage does only make sense in the balanced configuration. It is built fully balanced and can get out the most atvantage of the principle. Cartridges are in fact also balanced designs. I auditioned that phono twice and in unbalanced it is a completely unsexy device - bright and non spectacular at all. In balanced mode it opens up a bit more without harshness. But it overall tends to the brighter and analytically side.  
 
I also have my Benz cart cabled in balanced mode to a phonostage which can handle balanced input for carts and, at least in the signal input stage, separates the signal minus from the common ground. This results, compared to the unbalanced mode, into more clean and relaxed, yet transparent presentation.
der_yeti
14-01-16
23:04:55
回覆 (10): GRAAF OTL
Please take note of the following from Fremer’s review:  
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Ok, I take note because you say so. I have no problem with that but who is Fremer?  
 
bobui
14-01-16
22:20:51
回覆 (9): GRAAF OTL
>As for pin 1, would you like to ground the arm thru that?<  
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Please take note of the following from Fremer’s review:  
 
"it's critical that none of the cartridge pins contact ground. Most tonearms are so wired, but not all [the Regas have the left channel negative signal lead connected to ground, for example—Ed.] so check first. “  
 
thekong
14-01-16
11:13:19
回覆 (8): GRAAF OTL
Can I reterminate my tonearm cable in TRUE xlr with your cold special tool? I guess I need to solder only the positve and negative (2+, 3-) and float the 1 ground up. Is that what Aqvox claiming full balance connection?  
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Whether spot welding can be applied in this situation depends on the plugs, sockets and the way they are to be mounted. So I need a look at the real thing before I can be sure.  
 
Yes, there are of course only 4 connections to the cartridge, in balance mode these will occupy pin 2 & 3. As for pin 1, would you like to ground the arm thru that?
Derek2A3
14-01-16
10:03:53
回覆 (8): GRAAF OTL
While it probably doesn't have much technical information in Michael Fremer’s review in Stereophile, he did rave about the AQVOX.  
 
He also mentioned to take full advantage of the MC section, you need to use the balanced input (i.e, you need to terminate your tonearm cable with XLR plugs), and there are some points you need to be careful about grounding of the toneare cable.  
 
I was interested in getting one to try out, but the comment I got from other source was that, while the AQVOX was transparent, its sound was also rather cool. Even Fremer said the Nagra VPS was warm and supple in comparison! So, it is probably not really my cup of tea!  
http://www.stereophile.com/phonopreamps/708aqvox/index.html
thekong
14-01-16
09:04:34
回覆 (7): GRAAF OTL
Hi, Derek,  
 
I am not certain; I expect by-pass.  
 
http://www.aqvox.de/index_en.html  
 
Can I reterminate my tonearm cable in TRUE xlr with your cold special tool? I guess I need to solder only the positve and negative (2+, 3-) and float the 1 ground up. Is that what Aqvox claiming full balance connection?
dkyyu
14-01-15
17:08:06
回覆 (6): GRAAF OTL
Seems like "bridge" in this situation stands for "by pass"
Derek2A3
14-01-15
16:57:40
回覆 (5): GRAAF OTL
good sounding and bad sounding  
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and the ugly  
bobui
14-01-15
16:40:09
回覆 (4): GRAAF OTL
there is only two types, good sounding and bad sounding. the rest is hot air.
drwkng
14-01-15
15:17:33
回覆 (3): GRAAF OTL
Thank you sirs,  
 
That's what it says in Aqvox Q&A. No value or details given except a photo. With dr's endorsement, I am happy to bridge the phono output stage now.  
 
Dear King sir,  
 
One more technical. Aqvox claims they are providing 2 different type of phono stage in one single box, including the "rare to find" current amplified mode when connected low output MC cartridge to their xlr input, and also their Voltage amplify mode when connection of high outout or MM cartridge to their RCA input. They highly recommend the much better current mode in full balance connection. Any false or disguise xlr connection will defect their current mode design and effect.  
 
I bought eh Aqvox phono for 2 reasons:, true and fully balance; the option of current and voltage mode.  
 
As everybody well aware, I am truly a technical blind, I have never heard of these current mode. They claim the voltage mode even at best can only reach no more than 80% of current mode performance in phono stage when carrying such a small voltage. Any of your opinion to share? Why the current mode not widely used?  
 
Now I am thinking to rewire the phono cable toxlr connection. Any safe way to rewire my RCA to xlr?  
 
Yours faithfully  
 
Dennis  
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1b.- AQVOX Phonostages - bridging the output capacitorsFor our demanding audiophile customers:  
Later MKI and all MKII versions have internal DIP-switches to bridge the output-capacitors. Overall better sound, like more roominformation, transparency and so on...  
 
Attention!  
!!! The use of the switches is on own risk and without any guarantee for connected devices!  
If the connected Preamp/Amplifier has no Input-coupling-capacitors, heavy damages of devices, speakers and ear damages could happen!  
 
Attention!  
If you want to bridge the Phono2Ci´s output-caps, please ask the manufacturer of your Preamp/Amplifier that this Amp has capacitors (coupling-capacitors) at the input. Do this before you bridge the Phono2Ci´s output-caps. One side needs capacitors, either the Phono2Ci at the output, or the connected AMP at the input ! In case of questions contact AQVOX !  
 
DC free or AC coupled analog Outputstages.  
 
Attention!  
The internal DIP-Switches have following function:  
OFF = bridging is DISABLED (Capacitors are ON)  
ON = bridging is ENABLED (Capacitors are OFF)  
 
dkyyu
14-01-15
14:49:57
回覆 (2): GRAAF OTL
you don't need it. dennis. no dc can go thru your TVC.
drwkng
14-01-15
14:11:16
回覆 (1): GRAAF OTL
Dennis, what do you mean by bridge the phono amp output caps? Is it that you place a cap outside of the phono amp between its output and the preamp? What value is Aqvox suggesting? Its balanced, so you need two for each channel?  
 
bobui
14-01-15
13:57:34
GRAAF OTL
Can any c hing or si-fu advise me whether there is any "INPUT capacitors" inside Graaf OTL power amp?  
 
I am trying a new full balance Aqvox phono amp. The manual says users can bridge the Phono amp's output-caps for better sound quality. The Manufacturer asked me to check if any INPUT capacitors inside pre amp for safety reason.  
 
I am using Music First Audio passive TVC Baby Reference and a pair of Graaf Modena OTL power amps. I am sure no capacitor inside my passive pre. So I think I need to count on the power amp for protection when the Aqvox phono amp's output cap is bridged. Correct me if I am wrong.  
 
My worry is: what would happen if there is no input cap installed in my pre and power amp? Or should I ignore it at all, and simply go bridging the phono's output cap?
dkyyu
14-01-15
12:45:48
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