EV-1 Phono/Cartridge Match

[AnotherJohnson]

This is exactly what the manual says:

Load Selectors: To select an input load impedance other than the
factory preset 47 kohms unplug the EV-1 and remove the cover. The
input impedance of the EV-1 is set by the load selector switches - the two
dual inline pin (dip) switch arrays located near the input connectors at
the back of the unit. Each dip array includes four switches labeled 1
through 4. Load impedances are selected as follows:
impedance switch #
1 2 3 4
47 kohms o o o o
9.6 kohms x o o o
1.9 kohms o x o o
500 ohms o o x o
200 ohms o o o x
x indicates switch in "on" position
o indicates switch in "off" position (indicated by arrow on switch)
Be sure to set both switches. Replace cover. Do not operate the unit
with the cover off.

Gain: 50 dB
Maximum Output: 20V
RIAA Equalization: within 25 dB
Hum and noise: 82 dB below 10 mV input
Phase: phase correct
Output impedeance: less than 800 ohms

Tube Compliment: 2 x 12AX7, 1 x 5751, 1 x 12AU7

Mechanical:
DImension: 13D x 19W x 3.315H inches
Net Weight: 12 lbs

Fuses
The EV1's power transformer is protected by a fuse on the ac power line. A failure of this fuse is a symptom of a more serious problem, and a competent service technician should be consulted. In no event should the fuse be replaced with a value or type different than that originally supplied. The fuses are located in a pull out compartment in the ac power line receptacle on the back of the chassis. The correct fuse values are:

If configured for 100 or 120V 1/2 amp, slow blow
If confisgured for 220 or 240V 1/4 amp slow blow

Thanks for posting it!

The RIAA EQ spec must be missing the decimal point because that should be .25 rather than 25.

Could be a typo in the manual. It’s harmless because anyone who saw it would know it was wrong.

[SteveFord]

Nah, it's not the manual it's my failing eyebones.
A sinus surgery a few years destroyed my vision.

It's a good sounding unit, a big improvement over the Jolida.
I kind of figured that's what was holding things back.

[Joe Appierto]

The load selector switch settings are exactly what I posted on August 29th for the EF1. Guess they are the same.

[AnotherJohnson]

The load selector switch settings are exactly what I posted on August 29th for the EF1. Guess they are the same.

They look like typical CJ phono card settings.

I remember arguing with JF that I thought they should offer a 50 Ohm setting. He graciously said that they would customize it to whatever I thought I wanted.

After I bought my TEA2MAX I realized that it wasn’t necessary to super customize the load. Like my AR phono sections, the sensitivity wasn’t nearly as dramatic as I’d seen with solid state phono sections.

[Joe Appierto]

I am woefully ignorant when it comes to phonostages. The only one I ever had was when Bill Thalmann modified my PV10AL to a 10A by adding the phonostage to the preamp. It was MM only and had no settings. It fit my lack of expertise to a T.

Edit: I totally forgot that my old Marantz 4300 receiver had the MM input built-in.

[AnotherJohnson]

In the case of HOMC cartridges, the consensus is to load them like a MM, ie, 47kOhms. So it may not be an issue here anyway.

[Wildcat]

Having owned the EV-1 for a couple of years now, I can say that I did not like the higher output of this phono stage. I ended up having to borrow a friend's attenuators. The problem was that it was impossible to play my system at a really low level in the evenings, as I often like to do. On my preamp, setting it to 02 on the volume was even sometimes too loud.

They really should have added an adjustable output level to the EV-1.

I think I'm done with mine. I was having noise issues in my phono section. Swapping the EV-1 for my previous phono stage, the Musical Surroundings Phonomena II+ did improve the noise floor slightly, but I have other issues going on which I'll be testing.

That and to be honest, ever since I bought it, the EV-1 has sounded dull and lifeless, even with a new set of tubes. I'm not about to start tube rolling--for this instance, it's just throwing good money after bad in a wild attempt to see if the sound might improve. I have a feeling that something might be out of spec inside the EV1, due to age. The Phonomena II+ is more balanced top to bottom and has more life to it. The overall sound is better in every way, including soundstage and dynamics. And again, there's the lower noise floor. I switched back to a moving iron phono cartridge (the Nagaoka MP500) two years ago as I was also tired of trying to deal with the idiosyncrasies of moving coils, of which I've owned three. (And my experience with an SUT with the EV-1 was a disaster anyway.)

I'm debating dropping the EV-1 off with Music Technology if I decide to pick up my Premier 11 when Bill is done working on it, just to have it looked over.

Or it could be that I just don't like this phono stage.

[AnotherJohnson]

Having owned the EV-1 for a couple of years now, I can say that I did not like the higher output of this phono stage. I ended up having to borrow a friend's attenuators. The problem was that it was impossible to play my system at a really low level in the evenings, as I often like to do. On my preamp, setting it to 02 on the volume was even sometimes too loud.

They really should have added an adjustable output level to the EV-1.

50 dB of gain is enough to run a .5 mV to maybe 2.5 mV cartridge, give or take.

A typical MM or HOMC would be pretty loud. Might even overload it.

But it’s not really enough for a seriously low (.25 mV or less) cartridge.

So … it may be a bad match for what you’re using.

FWIW, after extensive testing, I’ve played out on the attenuators. They “just DONT sound right.”

FWIW #2, the EV-1 is pretty long in the tooth.

I think the Premier 15 was the true beginning of good CJ HG phono preamps. If I wanted a vintage phono stage for LOMC, I’d start there.

As for adjustable output levels, I’ve never seen a serious phono stage that included continuously variable gain. Some will have HG and LG settings. But once set, the gain “is what it is.”

This isn’t because they’re too cheap to add a volume control. It’s because a phono preamp is typically giving 15 to 30 dB more gain than a typical line level preamp already, and the errors in tracking would send many people running from the room.

[Wildcat]

The EV1 came after the Premier 15:

Based on the circuit used in conrad-johnson’s acclaimed Premier Fifteen, the EV1 used a single-ended triode input amplifier comprised of both sections of a miniature twin–triode tube connected in parallel for reduced noise. A second single-ended triode amplifier provided added gain. A passive network of precision components between these two stages set the required frequency equalization. A direct coupled cathode follower output stage yielded a low output impedance.

https://conradjohnson.com/vintage-conra ... -products/

Since the EF1 had an adjustable output gain with DIP switches, it is curious that the EV1 does not have this ability. Offering gains of 40dB, 50dB and 60dB in a phono stage, or even smaller increments between these values, are commonplace in most phono stages that I'm aware of. And honestly, since I'm using only higher output cartridges now, I have no need for any gain but 40-ish dB, and 49dB is just too much. (The attenuators worked with no issues between phono stage and preamp, but I'd rather not use them if I don't have to.)

My thoughts right now are to either have the EV1 looked at and see if there is anything wrong (which is possible), have it inspected and modified for 40dB gain, or sell it and cut my losses. I wouldn't be heartbroken to get rid of it.

But, better news at Casa Wildcat on the vinyl playback front. I can post it soon, once I get a spare moment to rewrite what was published elsewhere.

[AnotherJohnson]

Yes, I know it came after the Premiere 15.

But my personal opinion was that it was not a step forward. YMMV.

Yes, switched gains are nice. It would have been a plus. I must have misinterpreted your use of the word variable to mean continuously variable. My bad.

There is no disagreement that you don’t care for it.

Looking forward to the vinyl front news!

[AnotherJohnson]

Digging around …

https://www.soundstagenetwork.com/vinyl/vinyl200203.htm

Maybe this was posted before.

[Wildcat]

One interesting note in that Soundstage review is the added low-level noise. I hear that even with my high output cartridge and as such, I find it unsuitable for making digital transfers of vinyl. (I have many LPs never released digitally, and I'd like to play them beyond my main system.) I know that no phono preamp is dead silent but on the other hand, the EV1 has slightly higher background noise than any other phono preamp I have used in my system. This even after switching between three tonearm interconnects (the stock cable, an Audioquest, and a Morrow Audio).

I suppose I could have Music Tech look it over, and perhaps fix the gain so it is 40dB rather than 49dB. But I feel as though it's throwing good money after bad to put more money into it.

[admin]

If you are just having difficulty with the vinyl to digital transfer, have you considered getting a phono attenuator? A relatively inexpensive thing to try. You can get a 10 db attenuator for under $100. It may be worth a try before considering an expensive modification.

[Wildcat]

I already have a 10dB attenuator, but that only means I have to boost my recording level by 10dB to compensate, and the noise is still there. Not a big deal as I've swapped in the Phonomena and everything is sounding better, even though the background noise is only partly reduced. That is an issue I never had in my old system, so I am still tracking what is causing it. Part of it, though, was the EV1.

[AnotherJohnson]

You’ve probably done this … but a lot of times the background noise in a phono stage is tube generated.

Get a complement of low noise tubes, at least the two 12AX7s, and see if that doesn’t fix your problem. 49 dB is not a huge gain. I’ve got two that can do 70ish, and I would describe them as dead quiet at normal listening levels.

Another possibility that you’ve probably already considered is that the noise is on the vinyl. The high output cartridge could be exacerbating your awareness.

I had some serious phono noise the other day… I wasn’t paying attention and I plugged the 54 dB gain TEA2MAX into the 69 dB gain MC phono stage on the Levinson integrated amp. I turned the volume up a bit, and was startled into trimming back to 0. Then it dawned on me … don’t cascade phono stages please.

Mine was pure lack of focus for just a few seconds.

[AnotherJohnson]

FWIW, I agree with the “throwing good money after bad” analyses.

There are some modestly priced phono stages (less than $400) that have on board ADC and USB port, with variable output. They’re solid state and very quiet. Here’s one at Amazon by Rega for $195.

https://www.amazon.com/dp/B006GE9XQQ?ta ... slink=true

Here’s another at Crutchfield from NAD for $259.

https://www.crutchfield.com/S-EbBT0eZ5m ... M8QAvD_BwE

[admin]

I like AJ's idea. I would not hesitate to go with either one of the suggestions there. Rega knows what they are doing when it comes to anything vinyl related, and NAD focuses more on digital components. Both are in similar price ranges and seem like good options.

[AnotherJohnson]

On the cartridge-phono preamp gain matching, we never got around to your line stage, amp gains, and speaker efficiency.

Although this may not be helpful for your situation, a CA150 or CAV45 driving 85 dB sensitivity speakers would fair better with a 2.8 mV cartridge and 49 dB phono stage, than an ET7s2 and LP275Ms, driving 95 dB sensitivity speakers.

And then there is the personal volume preference issue.

FWIW, there are twin triodes that have lower gain than the 12AX7s, so a tube roll might help too, although I would not do it myself. That NAD PP4 is available for less than at Crutchfield. It might be just the ticket. I’ve personally owned both the Rega and NAD units I’ve suggested. I still have the NAD as an inexpensive spare. Both sound far better than would be expected for their price points.