most likely scenario:
PMA360, more or less nothing more than piece of drek, gave you augmented bass, due to inability to control it
be sure that - if properly made- F5T is being much more linear than Denon
anyhow, as Verity per se isn't most important goal, and we all are rather looking/searching for enjoyment and satisfaction ........ you have choice:
PMA360, more or less nothing more than piece of drek, gave you augmented bass, due to inability to control it
be sure that - if properly made- F5T is being much more linear than Denon
anyhow, as Verity per se isn't most important goal, and we all are rather looking/searching for enjoyment and satisfaction ........ you have choice:
- find better (or simply bigger) speakers, to mate with Iron Pre & F5T, or
- go back to Denon
Ouch, do you have to be so harsh?! My poor old Denon is looking very sad now 😢
All this got me thinking I need a more objective view on the issue. Unfortunately I don't own any measurement equipment. But I used a dB app on my cellphone and a test CD with subsequent tracks incrementally rising in frequency to measure my old speakers before. So I did that again. I used a 1k Hz 0 dB reference tone track from that same CD to more or less equal the volume. The cellphone app is neither precise nor accurate, so the results are not super clear. Still I could draw some conclusions. First: no LF roll off with the Iron Pre, it accually goes a little deeper. The results with the Iron Pre also seem a bit flatter. But there is a hump at 100 Hz with my old setup (that I noticed before). I always thought that was a classical room mode, but maybe not so. I have been listening to my old system for a very long time, so I guess my ears are completely accustomed to its sound. They need time to reset to true neutral...
I didn't said this before, but apart from my perceived lack of bass I think the Iron Pre - and I'm not trying to kiss up here - sounds absolutely wonderfull. Neutral, clear and very transparent, but also lively and very easy to listen to!
Something else: is there any way to put a fixed level output on the Iron Pre? I would like to be able to connect a headamp without using Y cables or switch boxes.
All this got me thinking I need a more objective view on the issue. Unfortunately I don't own any measurement equipment. But I used a dB app on my cellphone and a test CD with subsequent tracks incrementally rising in frequency to measure my old speakers before. So I did that again. I used a 1k Hz 0 dB reference tone track from that same CD to more or less equal the volume. The cellphone app is neither precise nor accurate, so the results are not super clear. Still I could draw some conclusions. First: no LF roll off with the Iron Pre, it accually goes a little deeper. The results with the Iron Pre also seem a bit flatter. But there is a hump at 100 Hz with my old setup (that I noticed before). I always thought that was a classical room mode, but maybe not so. I have been listening to my old system for a very long time, so I guess my ears are completely accustomed to its sound. They need time to reset to true neutral...
I didn't said this before, but apart from my perceived lack of bass I think the Iron Pre - and I'm not trying to kiss up here - sounds absolutely wonderfull. Neutral, clear and very transparent, but also lively and very easy to listen to!
Something else: is there any way to put a fixed level output on the Iron Pre? I would like to be able to connect a headamp without using Y cables or switch boxes.
point of dialog is nothing else than to (hopefully) find explanation of perceived phenomena, thus enabling development of solution
single dilemma I had is - is Iron Pre made by the book; once you established it is, I didn't had further suspicions
now, you're in situation of establishing amplification part of system much more honest and capable, thus highlighting weakest link in system - your speakers
I'm not saying they're bad per se (don't have enough details to say anything) but evidently not reaching your expectances regarding performance in bass region, in context of your listening space and habits of SPL
sidetracking but not really - my stance is (even if major generalization) - with A Class amplification, game begins from 10" cones and up .......... physic of things allowing to have both efficiency and sensitivity of speakers, which is absolutely necessary to have all benefits of A Class context
any smaller than 10" cone - for me that's near field monitoring, be it small or big space, irrelevant
if you're going (hopefully) to work on speakers - try inserting series power resistor in between amp and speaker - starting from 0R22 or so (5W upwards) - to mimic higher Rout of amp, invoking 100Hz bump again
if you like results, bingo - no need to change speakers at all
single dilemma I had is - is Iron Pre made by the book; once you established it is, I didn't had further suspicions
now, you're in situation of establishing amplification part of system much more honest and capable, thus highlighting weakest link in system - your speakers
I'm not saying they're bad per se (don't have enough details to say anything) but evidently not reaching your expectances regarding performance in bass region, in context of your listening space and habits of SPL
sidetracking but not really - my stance is (even if major generalization) - with A Class amplification, game begins from 10" cones and up .......... physic of things allowing to have both efficiency and sensitivity of speakers, which is absolutely necessary to have all benefits of A Class context
any smaller than 10" cone - for me that's near field monitoring, be it small or big space, irrelevant
if you're going (hopefully) to work on speakers - try inserting series power resistor in between amp and speaker - starting from 0R22 or so (5W upwards) - to mimic higher Rout of amp, invoking 100Hz bump again
if you like results, bingo - no need to change speakers at all
that meant to be:
.....to work on speakers - as temporary patch - try inserting series........
You're right, I never liked the bass of them. They're not my design, but from the german diy speaker magazine "HOBBY HiFi" (issue 4/2019, the "TBTL-W6 Mk 2").
Transmissionline, 4 Ohm, crossover points at 220 and 4,2k Hz, and yes 81 dB efficiency. I was rather smitten with this design, and overlooked that last spec, also not yet aware how important efficiency is.
I already made a modification by removing some damping materiaal from the mid drivers inner cabinets. That helped some. I'm planning to also remove some damping from the transmissionline. Funds prevent more costly modifications at the moment, like modifications in the crossover. I will try the patch! But finishing my Pearl 3 build first has priority since the phono pre in my Denon is as good as dead now.
Transmissionline, 4 Ohm, crossover points at 220 and 4,2k Hz, and yes 81 dB efficiency. I was rather smitten with this design, and overlooked that last spec, also not yet aware how important efficiency is.
I already made a modification by removing some damping materiaal from the mid drivers inner cabinets. That helped some. I'm planning to also remove some damping from the transmissionline. Funds prevent more costly modifications at the moment, like modifications in the crossover. I will try the patch! But finishing my Pearl 3 build first has priority since the phono pre in my Denon is as good as dead now.
if you just scratch and invest some time and patience, you can find enormous jewels on second hand market, for silly affordable price ........... in general , or at least looking at possible final result
just go big ....... and smart
coincidentally, I know that Netherland web adds are rich, at least for dumpster-diver as I am
and that, me even without proper local insight, practically knowing just Marktplaats
just go big ....... and smart
coincidentally, I know that Netherland web adds are rich, at least for dumpster-diver as I am
and that, me even without proper local insight, practically knowing just Marktplaats
My Fancy Shunt attenuator is the best. It has shifted my system to where I have 3d soundstage. for my SE build for the single wide trailer, I'm thinking a switch attenuator with MELPH. It will be cheap like the trailer. In my opinion, a simple shunt switch is the best way to attenuate. logic and relays no. just switch and calculate what resistors you need to stay in class a, then optimize and create vernier scale for your needs. Miles Tribute to Jack Johnson Complete Sessions is a thing of beauty. Peace.
point of dialog is nothing else than to (hopefully) find explanation of perceived phenomena, thus enabling development of solution
single dilemma I had is - is Iron Pre made by the book; once you established it is, I didn't had further suspicions
now, you're in situation of establishing amplification part of system much more honest and capable, thus highlighting weakest link in system - your speakers
I'm not saying they're bad per se (don't have enough details to say anything) but evidently not reaching your expectances regarding performance in bass region, in context of your listening space and habits of SPL
sidetracking but not really - my stance is (even if major generalization) - with A Class amplification, game begins from 10" cones and up .......... physic of things allowing to have both efficiency and sensitivity of speakers, which is absolutely necessary to have all benefits of A Class context
any smaller than 10" cone - for me that's near field monitoring, be it small or big space, irrelevant
if you're going (hopefully) to work on speakers - try inserting series power resistor in between amp and speaker - starting from 0R22 or so (5W upwards) - to mimic higher Rout of amp, invoking 100Hz bump again
if you like results, bingo - no need to change speakers at all
Some times you amaze me in that you so limit yourself.
Aleph 2s drive Maggie 1.7 speakers with aplomb.
No stinkin' little cones pushing air back and forth, no little amplifiers..... Just two big boxes generating lots of heat in our cold Southern California weather and two big 2001 like Obelisks in the living room imparting all kinds of wideband wisdom.
BTW, I'm confused (*).. what does the power resistor in series with the speaker do? Does it modify the crossover?
(*) In a Kubrick's 2001 way... show me an Obelisk, huh?
@stereonutty I also found that that the Iron Pre Bal has more bass in its balanced outputs than the SE. But then, I've only used a single amplifier to test this.... I've tried two different speakers though.
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I'm not sure that I'm limiting myself, stating my preference for big cones
Anyhow, be sure that I have drekload of spks, of all sizes; in fact, beside 15"-ers around, at least half of my music hours are spent with pair of Auratone 5C-like spks, each of my 2 screens sitting on one
And I have all sorts of sizes in between, be it cones or ribbons or fluffies (Heil)
Even (now just one ) pair of small Dynaudios .......... not because I need them, simply because I'm speaker Junkie
and amps - fact is that I'm making those for living; as Pa sez - favorite is most recent one
Size of it and power isn't important at all
resistors inserted in between amp and spk - read full sentence; search for Carver challenge, if you like
brain is fiddly creature; sometime you can invoke orgasm verrrrrrry cheap (if you're blessed enough)
Anyhow, be sure that I have drekload of spks, of all sizes; in fact, beside 15"-ers around, at least half of my music hours are spent with pair of Auratone 5C-like spks, each of my 2 screens sitting on one
And I have all sorts of sizes in between, be it cones or ribbons or fluffies (Heil)
Even (now just one ) pair of small Dynaudios .......... not because I need them, simply because I'm speaker Junkie
and amps - fact is that I'm making those for living; as Pa sez - favorite is most recent one
Size of it and power isn't important at all
resistors inserted in between amp and spk - read full sentence; search for Carver challenge, if you like
brain is fiddly creature; sometime you can invoke orgasm verrrrrrry cheap (if you're blessed enough)
Orgasms...
Remember Woody Allen's Orgasmatron?
https://www.google.com/search?q=Org...ate=ive&vld=cid:507f422d,vid:uZvpIE5g5Fo,st:0
It's the Carver Challenge that I'm curious about.
Your speakers... well, we know... those ones you displayed recently, the "coax?" with the weird scalloped cones... Beyond weird.
Why would I get more bass from the Iron Pre when I run it in balanced mode. It's not even subtle.
Remember Woody Allen's Orgasmatron?
https://www.google.com/search?q=Org...ate=ive&vld=cid:507f422d,vid:uZvpIE5g5Fo,st:0
It's the Carver Challenge that I'm curious about.
Your speakers... well, we know... those ones you displayed recently, the "coax?" with the weird scalloped cones... Beyond weird.
Why would I get more bass from the Iron Pre when I run it in balanced mode. It's not even subtle.
Dunno Bubba
try different amp/spks combo
hardly reason being in IPre freq. range, there is no change between SE vs. Bal
maybe you're getting some THD nulling effects, changing to Bal
try flipping spks phase to investigate what opposite phase of dominant is bringing to your ears
try different amp/spks combo
hardly reason being in IPre freq. range, there is no change between SE vs. Bal
maybe you're getting some THD nulling effects, changing to Bal
try flipping spks phase to investigate what opposite phase of dominant is bringing to your ears
Hi Mightiness,
not having a dedicated thread, I'm just asking here, are there any news re balanced Tanka?
not having a dedicated thread, I'm just asking here, are there any news re balanced Tanka?
For a moment you got me there, but then I remembered I posted pictures of it, working
So, pretty much I've done everything, except most tedious and troublesome part - counting it all, and doing calculus what complete kit should cost
Now, as I remember your intention - your own attenuator (whatever it is, no way being better than existing one, nested properly both electrically and physically) and logic-less
For that, you need to arrange one strategic detail - ideally introducing two cascaded timers - first one for delayed HT PSU and second one for un-mute relays
So, as I'm already used on situation of not having Trade threads (lazy and vague), feel free to buzz me ........ sorta urging me to do that gnarly part of work, from third line above
Technicalities about timers will be solved along
But, frankly, speaking from technological side of things, it'll be best to build is as intended, without changes;
Factually and logically - I'm not brightest and shiniest marble in the jar, but I really invested some work to make it as much optimized as I was able to
another one, through needle-eye, Public Disgrace avoided by smidge
edit: my own specimen, deliberatelly made in fugliest! industrial case, adequate front plate, so (hopefully) no one will try to buy it
that recipe works ...
3 Donuts are custom jobbies, static+magnetic shields, mains wires from back to front are shielded then taped with my fave Cloth Tesa
HiNi Cinemagzzzzz are happy, and undisturbed
edit: my own specimen, deliberatelly made in fugliest! industrial case, adequate front plate, so (hopefully) no one will try to buy it
that recipe works ...
3 Donuts are custom jobbies, static+magnetic shields, mains wires from back to front are shielded then taped with my fave Cloth Tesa
HiNi Cinemagzzzzz are happy, and undisturbed
So, pretty much I've done everything, except most tedious and troublesome part - counting it all, and doing calculus what complete kit should cost
Now, as I remember your intention - your own attenuator (whatever it is, no way being better than existing one, nested properly both electrically and physically) and logic-less
For that, you need to arrange one strategic detail - ideally introducing two cascaded timers - first one for delayed HT PSU and second one for un-mute relays
So, as I'm already used on situation of not having Trade threads (lazy and vague), feel free to buzz me ........ sorta urging me to do that gnarly part of work, from third line above
Technicalities about timers will be solved along
But, frankly, speaking from technological side of things, it'll be best to build is as intended, without changes;
Factually and logically - I'm not brightest and shiniest marble in the jar, but I really invested some work to make it as much optimized as I was able to
What is this Tanka? Some kind of turtle?Hi Mightiness,
not having a dedicated thread, I'm just asking here, are there any news re balanced Tanka?
Just a general question, that I've been wondering about. Sorry if it's a little off-topic.
If someone used a transformer with 2 separate 300 ohm primaries/secondaries, instead of center-tapped. What would people expect sound differences to be between:
1. Running the transformer as an autoformer for 6db gain, as here in the Iron Pre.
2. Primaries connected in parallel, secondaries in series to give a 150:600 step up ratio (also 6db gain).
Obviously (2.) would be isolated for DC, but would the (1.) autoformer option have different inductance that might make a sonic difference?
I'm mainly asking because I've been playing around with an old repeat-coil in various configurations. I'm currently using it DAC > transformer> ACP+, wired as a step-down autoformer (-6db voltage gain).
I've been wondering if this would make it easier to drive a power amp (ACA mini), as well as somehow improve my gain set-up (less thrown away in the preamp volume pot). I haven't had a problem with noise.
Anyway, sorry again for being pretty off-topic. I just thought wiser heads might be able to share some insight! I couldn't find much useful info in old books (Radiotron 3rd edition etc.)
If someone used a transformer with 2 separate 300 ohm primaries/secondaries, instead of center-tapped. What would people expect sound differences to be between:
1. Running the transformer as an autoformer for 6db gain, as here in the Iron Pre.
2. Primaries connected in parallel, secondaries in series to give a 150:600 step up ratio (also 6db gain).
Obviously (2.) would be isolated for DC, but would the (1.) autoformer option have different inductance that might make a sonic difference?
I'm mainly asking because I've been playing around with an old repeat-coil in various configurations. I'm currently using it DAC > transformer> ACP+, wired as a step-down autoformer (-6db voltage gain).
I've been wondering if this would make it easier to drive a power amp (ACA mini), as well as somehow improve my gain set-up (less thrown away in the preamp volume pot). I haven't had a problem with noise.
Anyway, sorry again for being pretty off-topic. I just thought wiser heads might be able to share some insight! I couldn't find much useful info in old books (Radiotron 3rd edition etc.)
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with exquisite made xformers there is small or no difference in sound between xformer and autoformer arrangement, proper driving capacity ensured
though, major difference is that is much easier to make exquisite autoformer than exquisite xformer
now, reply for 1. vs. 2. ....... just analyze resulting inductance and load which driving stage sees, and there is your answer
take in account that, with classic repeaters, so nominally 600:600, while having two sections in primary and two sections in secondary, each winding is nominally 150R
wakoo xformer logic
though, major difference is that is much easier to make exquisite autoformer than exquisite xformer
now, reply for 1. vs. 2. ....... just analyze resulting inductance and load which driving stage sees, and there is your answer
take in account that, with classic repeaters, so nominally 600:600, while having two sections in primary and two sections in secondary, each winding is nominally 150R
wakoo xformer logic