First impression: Herron VTPH-2A phono preamp
@scm My opinion and to address your comment.... I have owned all the various versions of the VTPH-1 and VTPH-2 through the current revision. Used the same table and cartridges when upgrading from the VTPH-1MC (with the latest revisions) to the VTPH-2. As really good as the VTPH-1MC was (and still is), there is a very nice gain in performance, not subtle, in the VTPH-2, and another not subtle improvement in the VTPH-2a (the current revision). It is an awesome performer. IMO, at the top of the list of phono stages. It would be a steal at three times its price. At its current retail price, it is outright grand larceny. I agree and don't see any need for me to have mm / high level inputs, either. I haven't heard a high output cartridge that has compelled me to move in that direction and give up the AT moving coil "house sound" and performance, or the Lyra moving coil performance. But it is a nice convenience and possibly even a simplification of manufacturing for Herron Audio. Increases the sellability when my heirs pry my stereo from my cold dead hands and liquidate my estate and stereo gear after my death in a [hopefully] distant decade. |
professorsvsu OP A ladder attenuator configuration (the best) https://ibb.co/kCLLKJ A 10k ladder has a max output impedance of 2.5k, and with the 30k of the 4B that's a 1:12 ratio, pity yours 25k if it's a ladder it will be 1:6 ratio, but saying that, it maybe fine as below you see that out of 30 audiophiles only two detected something below 1:10 We conducted 30 strong audiophile group listening, level matched using 1khz test cd at the speaker within 10th of a volt, then with music. Using an amp I made to be able to change the input impedance quickly, and my Lightspeed (a ladder) the group could not hear any difference from 1:100 ratio down to 1:10 ratio. A couple "thought" they heard something lower than 1:10, but it wasn't till 1:3 ratio that 50% thought they heard a difference. Cheers George |
@scm I don’t know what Herron uses in the VTPH-2a. He’s pretty accessible. Give him a call. I keep all my Herron Audio units as-is based on how the Keith has designed and implemented them. If Herron changes his recommended tube complement, I will let him do the rolling using individual tubes he has tested. I gave you my honest assessment amd experience over the last 20+ years of using VTSP-1 and -2 units. My enthusiasm is just a reflection of my opinion of their performance. |
Just to amplify what some of the others have said regarding the upgrade from the VTPH-2 to 2A, the improvements are easily heard in a more dynamic presentation (perhaps due to the quieter background), even sweeter treble and punchier bass. I've loved my VTPH-2 for years and now that its been upgraded to the 2A version, I'm even happier. BTW, not many people better to do business with than Keith Herron. YMMV. Thanks, Tim |
George, Thanks for the feedback that I requested. I too did a little bit of experimentation. Hooked up my Goldpoint SA1 to the VTPH-2A then directly into the back of my Bryston 4B3. Kicked up the gain on my amp to 29dB and nothing (just kidding). Actually, I have more than a sufficient amount of volume control. The only difference that MAY have occurred going this route as opposed to running through my Parasound JC 2 BP is a little better channel balance. |
almarg Al rob67 just let me know that the Lightspeed's logarithmic volume controls are at 12 o'clock for normal loud listening levels on his system. And as you know 12 o;clock is not even half volume yet, it's 2pm on the Lightspeed. As you can see absolutely no need for any more active preamp gain and the noise it brings. He also said the Lightspeed wins out over his Audio Research REF-5se and older Pass X1. He's now getting a battery for the Lightspeed and will hopefully do an update here on that. Gain structure he has. Lyra Etna SL 0.25mV > Herron 64db > Lightspeed 0db > Gryphon Antillion 30db > Wilson Sasha 90db His Turntable https://i.pinimg.com/originals/c5/da/d3/c5dad306fea0f6cdda772d0ed07c2425.jpg Cheers George |
+1 brf Another bit of information that would be good to know is what kind of music Rob67 used in this evaluation. Volume levels tend to be set based on the average volume of the music, rather than on the volume of brief dynamic peaks. My understanding is that the majority of pop and rock recordings are dynamically compressed such that peaks require less than 10x as much power as the average level of the recording (corresponding to a 10 db peak-to-average ratio). While many well engineered classical symphonic recordings may require 1000x as much power for brief dynamic peaks as for the average level (corresponding to a 30 db peak-to-average ratio), which will usually result in the listener setting the volume control much higher than for a highly compressed recording. In any event, what is undeniable is that 64 db of gain will boost 0.25 mV to 0.396 Volts. Although as I mentioned earlier the dynamic peaks of some recordings may result in a cartridge output significantly greater than under the standard test conditions upon which the cartridge's output rating is based. Best regards, -- Al |
Almarg and George I have the Herron phono and I tried it at length with a transformer paste passive. While it sounded good and very transparent I did go back to an active line stage due to feeling like there was a slight lack of bass impact and slight lack of dynamics. I used to be a believer in passive preamps but now after that experiment changed my mind. It's good to see another individual discovered the benefits of Herron gear. Keith is great to deal with and I like that his products are not up in the rip off pricing category. I have heard many phonos costing more than twice as much but still would choose the Herron. I constantly look at the gear for sale ads but never once think of changing out my phono anymore. |
beatlebum wrote "Just to amplify what some of the others have said regarding the upgrade from the VTPH-2 to 2A, the improvements are easily heard in a more dynamic presentation (perhaps due to the quieter background), even sweeter treble and punchier bass." I've had the VTPH-2 for 11 years and upgraded to the 2A last March. My findings agree completely with beatlebum. Far and away though, the thing that most caught my attention was the punch factor, everything is mow tight as a tick. I can now follow any bass line, hear kick drums as distinct entities, and just in general I sit and marvel at the sound. |
Just to clarify further about the passive preamp versus the active one, even with the passive I could easily get lots of volume. That wasn't the issue that made me go back to active.And one of the reasons why Scm is having success with his passive configuration is because he added it to buffer. That changes everything. He said himself in his one post that now he runs the volume at a I am of The opposite mindset of George, I wish amplifiers had less gain. It's easier for preamplifiers to not mess up the sound so I would rather establish the gain earlier on in the system and just have amplifiers providing the current when needed. |
I am of The opposite mindset of George, I wish amplifiers had less gain. It's easier for preamplifiers to not mess up the sound so I would rather establish the gain earlier on in the system and just have amplifiers providing the current when needed.I'll go one further than that, I wish also that there was no gain the amp just used for current, but all the gain needed being in the source (which it can be), with it's gain being adjustable for volume. Which funnily is a direct source to amp connection or via a passive. What ever the source has, use it all, and stop shunting it back to ground with the volume control, because you have too much gain down the line, eg: the preamp gain section and amp gain. Cheers George |
I have posted this in another thread but is also relevant here: I have now had a good listen to my dual mono version of the LSA. To my ears (and friend's and family's) It has bettered the pre-amps i have had in this system so far, including ARC Ref5se (the Ref 5se was nice with the ARC amps i had previously, (perhaps at a disadvantage due to an impedance issue with ARC & Current SS amp ??). Among other great tube pres, I also compared an older SS Pass X2.5 and Bryston BP20. George was extremely helpful; not just in confirming impedance compatibility with my current equipment, potential PSU upgrades, but also general audio advice and a friendly approach to my many questions. My Current system is: 0.25mV MC Cart > Herron VTPH2 phono stage > LSA > Gryphon Antileon Signature > Wilson Sasha. Herron is configured to lower gain 64dB. Levels are fine, i am running at 12-2 o'clock, or just past half way for comfortable to strong levels. Although my room is not large, there is still plenty of gain available (not from the LSA of course). I wont go into its sound too much other than to say it seems to have no sound, very neutral and balanced. When i placed other preamps back in to compare it became apparent what colourations those other pres contributed to the sound, some aspects of which were enjoyable of course but ultimately there was too much trade off. I prefer the clean, open, neutral, balanced sound I am getting with the LSA. Perhaps eventually I will discover a Pre that betters the LSA in my current system, (I'm sure when i do it will be in excess of 20x the price) or i may change a component and find it an impedance mismatch with LSA. However at this stage, with my current setup it is very impressive and very good value sonically. Thank you George |
rob67Your very welcome Rob, and thank you very much for the kind words. Glad you like it so much and how it sounds, you’ve said it like it is. Are you going to try the 12v Li-Ion rechargeable battery to power the Lightspeed with? It will give a good week of listening before a recharge is needed. https://www.ebay.com/itm/EU-DC-12V-6800mAh-Portable-Rechargeable-Li-ion-Battery-Pack-fr-CCTV-Cam-Mon... Cheers George |
I owned the VTPH-1MC for 14 Years and upgraded to the VTPH-2A just recently. I can relate exactly to what the OP has stated here. I have used a number of Reference Tracks for Years and by Track 2 I was startled and by Track 5 I had a Shiver. Did not wet myself but the performance increase from the VTPH-1MC was not subtle and the better half also heard this. I wish to Thank You for all of your Posts since it is the largest performance increase on the equipment side in my household to date. I urge anyone on the fence in buying one of these to do so in the very near future since Keith Herron indicated to me that he has plans to possibly Retire within the next Year. |
djohn, I've had the VTPH-2A for about six months now and have not been disappointed one bit. Keith Herron must have been divinely inspired when he came up with this beast. If he retires, the listening community will be at a loss. His skill, talent, and passion are very much relevant in a market of overpriced, mediocre crap. |
Keith has said the majority of the improvement in the VTPH-2 compared to the VTPH-1 is in the MC circuit of the phono amp. For users of high output pickups (moving magnet and moving iron)---whose signal does not pass through the MC circuit---the improvement provided by the mm-2 in relation to the mm-1 is not as pronounced. That's purely academic, as the VTPHmm-1 is no longer offered, and mm-1 owners don't sell theirs! |
Extremely nice words and I agree the listening community will be at a loss. |
@jw944ts Al’s math is right. A doubling of output power to your speakers corresponds *approximately* (not exactly) to +3 decibels of increased SPL. But the gain from a phono stage is not amplifying power - it is amplifying the source signal’s voltage. When you double the voltage signal input to your power amplifier (e.g. from 0.5 V to 1.0 V), a linear amp responds by outputting twice the voltage AND necessarily twice (approximately) the current - because the speaker load (represented by R in ohms) remains constant and the law is: V = I * R. Since power is V * I (voltage times current), you end you with 4 times the output power from the doubling of signal voltage! Therefore a doubling of gain in your phono stage corresponds to (approximately) a +6 dB increase in SPL. This is also why bridging a stereo amplifier to mono nets you up to 4 times the output power, not just 2 times (assuming the power supply and heatsinks and output stage are up to task). It’s not "magic" or free power - the amp is working all that much harder to push the extra current (and be very wary of hooking a bridged amp into 4 ohm and less speakers)! This means 60 dB of phono gain is approximately equivalent to an amplification factor of 2^10 (a 6 dB voltage doubling, 10 times) or 1,024. More exactly, 60 dB of gain is exactly equal to 10 ^ 3 = 1,000 - since 20 dB corresponds exactly (not roughly) to a voltage multiplier of 10x. The 3dB / 6 dB doubling rules-of-hand are a (close) approximation to make the math easier by tossing out some nasty decimal digits. In short, a doubling of voltage (in most applications) results in a SPL increase of approximately +6dB; a 10x voltage amplification factor is exactly +20dB. You can mix-and-match these two shortcuts to approximate a wide range of gains. E.g. 32dB = 20dB + 6dB + 6dB = 10 * 2 * 2 = a voltage amplification factor of 40 times (decibels are added as amplification factors are multiplied). A doubling of *power* is an SPL increase of approximately +3dB; a 10x power amplification factor is exactlyequal to +10dB. Use these shorthand rules to impress your friends with Rainman-like quick calculations :) Also, the VTPH-2A is a very nice sounding phono stage :) |
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@mulveling , thanks for providing the comprehensive response to the question posed by @jw944ts. In doing so you saved me a lot of time, and I of course agree with what you wrote. JW’s calculation reflects a commonly held misconception that a "voltage db" and a "power db" both correspond to 10x the logarithm of the ratio between two voltages or two power levels, respectively. But they don’t, at least in terms of generally accepted usage, if not etymology as well. 10x is the proper multiplier to use when computing the difference between two power levels in db, but 20x is the multiplier that should be used in computing the difference between two voltage levels in db. A db is a db. It is not either a voltage db or a power db. The numerical result will be the same regardless of whether the number of db is calculated from voltages or from power levels, assuming impedances are the same in the two cases. That is a consequence of the fact that if impedances are the same power is proportional to voltage squared, as mulveling indicated. And therefore squaring a 2x increase in the voltage provided into a given impedance corresponds to supplying 4x the power, not 2x. (In the interests of simplicity I’m putting aside effects that occur when the load impedance is not purely resistive). And assuming the speakers and the rest of the system are operated within limits that allow them to perform in an essentially linear manner, a gain of 66 db corresponds to a voltage multiplication of about 1995x, that commonly being rounded off to 2000x. (20 x log(1995) = 66 db, where "log" is the base-10 logarithm). And if everything else is equal that results in approximately 4,000,000x (2000 squared) as much power being delivered to the speakers, and correspondingly to an approximate SPL increase of the same 66 db. (10 x log(1995 x 1995) = 66 db). Regards, -- Al |
