[TomSix]

Thanks so much for the detailed reply! How about sending my ST6 and supplied teflon caps to ALO? Would they be able to swap them out? I know shipping and labor might be an expense. Do you think it’s worth it?

That’s a possibility.

Unfortunately Ken the president of ALO has just now entered isolation due to Covid illness.

Perhaps in a few weeks time contact Ken at ALO directly and inquire.

If they have the time and bandwidth at present, they *might* be able to accommodate this.

Likely it would be helpful if you were to obtain the capacitors from a vendor of your choosing, once it is indeed verified that ALO would presently be able to accommodate the work, and then simply send them along with your amplifier. I believe the ALO stock of the PTFE capacitors may be zero, but you can certainly ask.

I can’t promise anything, because I’m around 800 miles from ALO, and not privy to the exact situation in the ALO workshop these days.

Feel free to private message me here in HeadFi if you have any other questions about the PTFE capacitors etc

 

[fzman]

@TomSix I have a few questions about the tech specs of the 'Six'. I am using some 42 R, 87dB/mw cans, and a phono preamp with low-ish gain (not sure the exact spec-- I built it, and have not measured).
On LPs cut at somewhat low levels, I can turn the volume control all the way up, and want a bit more.....

On digital sources, my dac produces sufficient output level that i do not "run out of" range on the volume control. I have added a line stage between the phono pre and the Six, which gives it about 6 dB gain, and that gives me enoough range.

So, does the choice of specific 6SN7s and 6V6's have much bearing on the gain/output levels? Do the regulators or the recifiier play any significant role in output levels either? Not unhappy, it sounds great, just curious as I do not really like to mess with the amp too much, as it is sounding so freakishly good already.

Thanks for reading this - any thoughts are w4elcome

 

[TomSix]

@TomSix I have a few questions about the tech specs of the 'Six'. I am using some 42 R, 87dB/mw cans, and a phono preamp with low-ish gain (not sure the exact spec-- I built it, and have not measured).
On LPs cut at somewhat low levels, I can turn the volume control all the way up, and want a bit more.....

On digital sources, my dac produces sufficient output level that i do not "run out of" range on the volume control. I have added a line stage between the phono pre and the Six, which gives it about 6 dB gain, and that gives me enoough range.

So, does the choice of specific 6SN7s and 6V6's have much bearing on the gain/output levels? Do the regulators or the recifiier play any significant role in output levels either? Not unhappy, it sounds great, just curious as I do not really like to mess with the amp too much, as it is sounding so freakishly good already.

Thanks for reading this - any thoughts are w4elcome

The gain of the phono stage was designed so that a wide range of phono cartridge output voltages could be accommodated effectively with adequate volume being produced with most headphones.

Its not a problem to use an additional preamp as you describe, although the input impedance of the added preamp should be no less than 47k Ohms and ideally closer to 100k Ohms in order to minimize unintended/excess bass roll-off and also maintain good linearity (low distortion) from the phono stage’s output tube.

To answer your other questions: There are no alternate tube types which could be selected to increase the gain or output power of the Studio-Six without causing unintended problems and/or degradation of some of the unit’s operating/performance parameters.

Also: the regulator tubes and rectifier, in particular, they play no role whatever in determining the gain of the amplifier.

The Studio-Six circuit was engineered very carefully to provide good drive to a wide variety of headphone types/sensitivities along with producing low distortion and excellent high and low frequency extension. Relatively small changes to the existing circuit can easily produce unintended performance degradations of various sorts.

I hope this is helpful

—Thomas

 

[fzman]

The gain of the phono stage was designed so that a wide range of phono cartridge output voltages could be accommodated effectively with adequate volume being produced with most headphones.

Its not a problem to use an additional preamp as you describe, although the input impedance of the added preamp should be no less than 47k Ohms and ideally closer to 100k Ohms in order to minimize unintended/excess bass roll-off and also maintain good linearity (low distortion) from the phono stage’s output tube.

To answer your other questions: There are no alternate tube types which could be selected to increase the gain or output power of the Studio-Six without causing unintended problems and/or degradation of some of the unit’s operating/performance parameters.

Also: the regulator tubes and rectifier, in particular, they play no role whatever in determining the gain of the amplifier.

The Studio-Six circuit was engineered very carefully to provide good drive to a wide variety of headphone types/sensitivities along with producing low distortion and excellent high and low frequency extension. Relatively small changes to the existing circuit can easily produce unintended performance degradations of various sorts.

I hope this is helpful

—Thomas

The signall flow is turntable, phono preamp, line stage preamp, Studio Six. The phono pre and line stage are home-built by me, from schematics provided by a friend. The system sounds great, and plays 'loudly enough'. I was not asking to change tube-types or ater internal components in the 'Six', just wondering whether some NOS tube brands may be note for a bit more output than others. I do not have a tube tester, and have been out of the tube gear club for a while, so was also wondering if subtly diminishing output levels were a symptom of tubes ebtering retirement age.....

 

[TomSix]

The signall flow is turntable, phono preamp, line stage preamp, Studio Six. The phono pre and line stage are home-built by me, from schematics provided by a friend. The system sounds great, and plays 'loudly enough'. I was not asking to change tube-types or ater internal components in the 'Six', just wondering whether some NOS tube brands may be note for a bit more output than others. I do not have a tube tester, and have been out of the tube gear club for a while, so was also wondering if subtly diminishing output levels were a symptom of tubes ebtering retirement age.....

Tube voltage gain is generally a *relatively* stable parameter with tube aging, and so this is unlikely an issue.

Of note: JJ 6V6 tubes are unusual in that they produce somewhat less gain in triode-mode as compared to any other current production or NOS tubes I have used. This is usually not problematic, but it is worth being aware of.

My mistake: I was thinking for a moment you were using the ALO companion phono stage with your Studio-Six, rather than the self-constructed phono preamp you mention.

As I understand your issue, it seems apparent your DIY phono preamp does not develop at least a 2-Volt RMS average output level with your chosen phono cart, and so cannot drive the Studio-Six to full volume.

In this situation, you could either add an additional gain stage to your DIY phono preamp, or merely continue using the additional separate preamp for a signal boost as Mentioned.

At any rate, it’s clear the gain of the Studio-Six is not the problem in this instance, and so I’d suggest you are already on the right track in solving the issue via boosting the level from your DIY phono preamp

 

[fzman]

Having not done any tube rolling for a while, i just swapped out a 1950's Sylvania 6SN7 for a Sylvanis VT-231 with the annchor logo on the base, opposite the side with the designation on it. It 'sounds louder' than the non- Mil spec tube. I know that 'sounds louder' is vague and subjective, and does not mean that there is actually higher output in V, A or dB.... It does sound a bit fuller in the mids and up, e.g., but deifintiely ounder and more detailed. (same gear, volume control untouched, etc.) So, here's a qwuestion:

In general, do Mil-Spec and/or JAN tubes sound better/different than their 'civilian' counterparts? -- If so, does the Mil-spec-iness of them dimish the differences from brand to brand?

Really digging this 6SN7 dto go with my Ken-Rad VT-207 6V6s....

thanks for reading this. Especially curious what Tomsix might have to say (though if he wants to remain silent, or pm me, that's ok too.) Happy Friday everyone

 

[TomSix]

Having not done any tube rolling for a while, i just swapped out a 1950's Sylvania 6SN7 for a Sylvanis VT-231 with the annchor logo on the base, opposite the side with the designation on it. It 'sounds louder' than the non- Mil spec tube. I know that 'sounds louder' is vague and subjective, and does not mean that there is actually higher output in V, A or dB.... It does sound a bit fuller in the mids and up, e.g., but deifintiely ounder and more detailed. (same gear, volume control untouched, etc.) So, here's a qwuestion:

In general, do Mil-Spec and/or JAN tubes sound better/different than their 'civilian' counterparts? -- If so, does the Mil-spec-iness of them dimish the differences from brand to brand?

Really digging this 6SN7 dto go with my Ken-Rad VT-207 6V6s....

thanks for reading this. Especially curious what Tomsix might have to say (though if he wants to remain silent, or pm me, that's ok too.) Happy Friday everyone

This is a very good question.

Regarding whether mil-spec tubes such as JAN tubes etc sound better than commercial/civilian counterparts:

There is no set rule which can be reliably used.

Sometimes a particular type and variety of JAN tube will sound excellent, whereas in other instances there may well be other NOS non-military variants which are generally found to be superior subjectively.

It‘s simply a question which must be explored via a case by case basis of comparison.

What is generally true about mil-spec/JAN tubes is that they tend to be quite physically (and often electrically) rugged as compared to most civilian/commercial variants, and the quality control is very good.

There are times a mil-spec/JAN tube variant will be found to *not* sound very good as compared to civilian/commercial counterparts. A noteworthy example of this are the Bendix/ Red Bank versions of the 6V6. These tubes are very ruggedly constructed and have exceptional reliability, however… The sound quality of these Bendix tubes was found to be less engaging than any other type or make of 6V6 tube tried at ALO with use in the Studio-Six. This was surprising, and somewhat ironic given the high physical quality of these NOS tubes and the quite high prices they fetch on the market these days.

And so… again, as far as potential sound quality merit, it’s best not to assume too much from a tube’s industrial or military pedigree.

Personally, some of my favorite tubes do happen to be JAN variants, but I find perhaps just as many of my favorites are *not* mil-spec/JAN tubes.

 

[fzman]

Thanks, Tom. Still trying to get the lay of the tube land, as much as possible.... Luckily the amp sounds great. Period! None of the tubes I've tried sounded bad, and the differences are small but important. That siad, since I was on a roll with the VT-231 and putting these Heddphones thru their paces, I swpaped out a MP of Fivres for the Ken-Rad VT-107s. Short version: The Fivres are more transparent/detailed/open, without being glare-y. They have more texture, but do not get 'crunchy'..... They still hit pretty hard, but may have a touch less bottom-end fulness. Putting hours on them now. Switched back from LP to digital, Dream Theater As I Am, playing as I type this...

on further review, i have to say ix-nay on the ass-bay comment. This set of tubes has some bottom.... Mongo like bass.

 

[longbowbbs]

I love my Sylvania VT-231. Good vibes.

 

[fzman]

We can form a fan club - called the blue dots? Don't know if it'll catch on, or just be a 'flash' in the pan

 

[longbowbbs]

HAHA!!

 

[TomSix]

Sad news from Portland.

James Moore, ALO Chief Technician and Master Assembler, passed suddenly and unexpectedly last week at age 67 —too young.

Jim had been a core member of ALO and Campfire Audio for over a decade. He was a multi-faceted multi-skilled individual, and served in multiple capacities and roles.

Assembly, testing, quality control, inventory management, manufacturing and assembly protocol and procedure development, facilities maintenance and repair, and more —Jim wore many hats at ALO.

Whatever was needed, whatever situation arose, Jim was the kind of guy who was “ON IT! “ and got it done right.

Jim was a person of unusually broad aptitudes and diverse skills, truly a polymath and something of a genuine ‘renaissance man’. He was a masterful carpenter, doing beautiful work in both wood and bamboo, he was an active visual artist, longtime musician and songwriter, a lover of all things quality, taking pleasure in repairing and restoring vintage and antique things of all sorts. Jim could often be seen driving around Portland in his lovingly maintained original WWII military Jeep.

Quality was of central importance to Jim. If he had a hand in a project, task or undertaking, then you could be certain the job would be done right. Quality, integrity and attention to detail: in creative endeavors, in interpersonal relationships, in all things, in life —this is the Jim I will always know, remember, and sincerely miss.

Jim’s easy and down-to-earth demeanor, his fantastic mischievous sense of humor, his easy smile, his (forgivable) morning crankiness encountered when one confronted him before he finished his coffee, his generous and helpful attitude—these are things so difficult to adequately convey in writing…

All owner/users of the Studio-Six should know: your amplifier and/or phono stage ( 99% of them) were assembled and tested by Jim. Carefully, meticulously, consistently, from start to finish, every time, every one.

Jim’s departure leaves a deep void at ALO. ALO chief Ken Ball is frankly struggling, trying to process the personal loss, the sadness…

Above all, Jim was a beloved friend to us who have had the privilege to work with him, to spend time with him inside and outside of the workshop.

We miss you Jim —really miss you. We love you buddy.

 

[MelaVerde]

Sad news from Portland.

James Moore, ALO Chief Technician and Master Assembler, passed suddenly and unexpectedly last week at age 67 —too young.

Jim had been a core member of ALO and Campfire Audio for over a decade. He was a multi-faceted multi-skilled individual, and served in many capacities and roles.

Assembly, testing, quality control, inventory management, manufacturing and assembly protocol and procedure development, facilities maintenance and repair, and more —Jim wore many hats at ALO.

Whatever was needed, whatever situation arose, Jim was the kind of guy who was “ON IT! “ and got it done right.

Jim was a person of unusually broad aptitudes and diverse skills, truly a polymath and something of a genuine ‘renaissance man’. He was a masterful carpenter, doing beautiful work in both wood and bamboo; he was an active visual artist, longtime musician and songwriter, a lover of all things quality and took pleasure in repairing and restoring antique and vintage things of all sorts. Jim could often be seen driving around Portland in his lovingly maintained original WWII military Jeep.

Quality was of central importance to Jim. If he had a hand in any project, task or undertaking, then you could be certain the job would be done right. Quality, Integrity and attention to detail, in all things, in creative endeavors, in interpersonal relationships, in life —this is the Jim I will always know, remember, and sincerely miss.

His easy and down to earth demeanor, his fantastic mischievous sense of humor, his easy smile, his (forgivable) morning crankiness encountered when one confronted him before he finished his coffee, his generous and helpful attitude—these are things so difficult to adequately convey in writing…

All owner/users of the Studio-Six should know: your amplifier and/or phono stage ( 99% of them) were assembled and tested by Jim. Carefully, meticulously, consistently, from start to finish, every time, every one.

Jim’s departure leaves a deep void at ALO. ALO chief Ken Ball is frankly struggling, to process the loss, the sadness. Above all, Jim was beloved friend to all of us who have had the privilege to work with him, to spend time with him, inside and outside of the workshop.

We miss you Jim —really miss you. We love you buddy.

What a huge loss for his and the ALO family, friends and the community as whole; I will treasure every single moment the wonderful products Jim helped build, farewell Jim!!!!

 

[longbowbbs]

Truly sad news. Thanks for the great work, Jim! You leave a special legacy.

 

[artemus77]

So sad to hear about Jim. Condolences to the ALO Audio family.